From cdd4d7832d51e0414472eb2863b294b783597e5e Mon Sep 17 00:00:00 2001
From: Mike Snitzer <snitzer@redhat.com>
Date: Mon, 12 Jul 2021 16:47:15 -0400
Subject: dm writecache: split up writecache_map() to improve code readability

writecache_map() has grown too large and can be confusing to read given
all the goto statements.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-writecache.c | 338 +++++++++++++++++++++++++--------------------
 1 file changed, 187 insertions(+), 151 deletions(-)

diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 3d2cf811ec3e..53076c7f4a34 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -1293,10 +1293,164 @@ static void writecache_offload_bio(struct dm_writecache *wc, struct bio *bio)
 	bio_list_add(&wc->flush_list, bio);
 }
 
-static int writecache_map(struct dm_target *ti, struct bio *bio)
+enum wc_map_op {
+	WC_MAP_SUBMIT,
+	WC_MAP_REMAP,
+	WC_MAP_REMAP_ORIGIN,
+	WC_MAP_RETURN,
+	WC_MAP_ERROR,
+};
+
+static enum wc_map_op writecache_map_read(struct dm_writecache *wc, struct bio *bio)
 {
+	enum wc_map_op map_op;
 	struct wc_entry *e;
+
+read_next_block:
+	e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING);
+	if (e && read_original_sector(wc, e) == bio->bi_iter.bi_sector) {
+		if (WC_MODE_PMEM(wc)) {
+			bio_copy_block(wc, bio, memory_data(wc, e));
+			if (bio->bi_iter.bi_size)
+				goto read_next_block;
+			map_op = WC_MAP_SUBMIT;
+		} else {
+			dm_accept_partial_bio(bio, wc->block_size >> SECTOR_SHIFT);
+			bio_set_dev(bio, wc->ssd_dev->bdev);
+			bio->bi_iter.bi_sector = cache_sector(wc, e);
+			if (!writecache_entry_is_committed(wc, e))
+				writecache_wait_for_ios(wc, WRITE);
+			map_op = WC_MAP_REMAP;
+		}
+	} else {
+		if (e) {
+			sector_t next_boundary =
+				read_original_sector(wc, e) - bio->bi_iter.bi_sector;
+			if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT)
+				dm_accept_partial_bio(bio, next_boundary);
+		}
+		map_op = WC_MAP_REMAP_ORIGIN;
+	}
+
+	return map_op;
+}
+
+static enum wc_map_op writecache_bio_copy_ssd(struct dm_writecache *wc, struct bio *bio,
+					      struct wc_entry *e, bool search_used)
+{
+	unsigned bio_size = wc->block_size;
+	sector_t start_cache_sec = cache_sector(wc, e);
+	sector_t current_cache_sec = start_cache_sec + (bio_size >> SECTOR_SHIFT);
+
+	while (bio_size < bio->bi_iter.bi_size) {
+		if (!search_used) {
+			struct wc_entry *f = writecache_pop_from_freelist(wc, current_cache_sec);
+			if (!f)
+				break;
+			write_original_sector_seq_count(wc, f, bio->bi_iter.bi_sector +
+							(bio_size >> SECTOR_SHIFT), wc->seq_count);
+			writecache_insert_entry(wc, f);
+			wc->uncommitted_blocks++;
+		} else {
+			struct wc_entry *f;
+			struct rb_node *next = rb_next(&e->rb_node);
+			if (!next)
+				break;
+			f = container_of(next, struct wc_entry, rb_node);
+			if (f != e + 1)
+				break;
+			if (read_original_sector(wc, f) !=
+			    read_original_sector(wc, e) + (wc->block_size >> SECTOR_SHIFT))
+				break;
+			if (unlikely(f->write_in_progress))
+				break;
+			if (writecache_entry_is_committed(wc, f))
+				wc->overwrote_committed = true;
+			e = f;
+		}
+		bio_size += wc->block_size;
+		current_cache_sec += wc->block_size >> SECTOR_SHIFT;
+	}
+
+	bio_set_dev(bio, wc->ssd_dev->bdev);
+	bio->bi_iter.bi_sector = start_cache_sec;
+	dm_accept_partial_bio(bio, bio_size >> SECTOR_SHIFT);
+
+	if (unlikely(wc->uncommitted_blocks >= wc->autocommit_blocks)) {
+		wc->uncommitted_blocks = 0;
+		queue_work(wc->writeback_wq, &wc->flush_work);
+	} else {
+		writecache_schedule_autocommit(wc);
+	}
+
+	return WC_MAP_REMAP;
+}
+
+static enum wc_map_op writecache_map_write(struct dm_writecache *wc, struct bio *bio)
+{
+	struct wc_entry *e;
+
+	do {
+		bool found_entry = false;
+		bool search_used = false;
+		if (writecache_has_error(wc))
+			return WC_MAP_ERROR;
+		e = writecache_find_entry(wc, bio->bi_iter.bi_sector, 0);
+		if (e) {
+			if (!writecache_entry_is_committed(wc, e)) {
+				search_used = true;
+				goto bio_copy;
+			}
+			if (!WC_MODE_PMEM(wc) && !e->write_in_progress) {
+				wc->overwrote_committed = true;
+				search_used = true;
+				goto bio_copy;
+			}
+			found_entry = true;
+		} else {
+			if (unlikely(wc->cleaner) ||
+			    (wc->metadata_only && !(bio->bi_opf & REQ_META)))
+				goto direct_write;
+		}
+		e = writecache_pop_from_freelist(wc, (sector_t)-1);
+		if (unlikely(!e)) {
+			if (!WC_MODE_PMEM(wc) && !found_entry) {
+direct_write:
+				e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING);
+				if (e) {
+					sector_t next_boundary = read_original_sector(wc, e) - bio->bi_iter.bi_sector;
+					BUG_ON(!next_boundary);
+					if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT) {
+						dm_accept_partial_bio(bio, next_boundary);
+					}
+				}
+				return WC_MAP_REMAP_ORIGIN;
+			}
+			writecache_wait_on_freelist(wc);
+			continue;
+		}
+		write_original_sector_seq_count(wc, e, bio->bi_iter.bi_sector, wc->seq_count);
+		writecache_insert_entry(wc, e);
+		wc->uncommitted_blocks++;
+bio_copy:
+		if (WC_MODE_PMEM(wc))
+			bio_copy_block(wc, bio, memory_data(wc, e));
+		else
+			return writecache_bio_copy_ssd(wc, bio, e, search_used);
+	} while (bio->bi_iter.bi_size);
+
+	if (unlikely(bio->bi_opf & REQ_FUA || wc->uncommitted_blocks >= wc->autocommit_blocks))
+		writecache_flush(wc);
+	else
+		writecache_schedule_autocommit(wc);
+
+	return WC_MAP_SUBMIT;
+}
+
+static int writecache_map(struct dm_target *ti, struct bio *bio)
+{
 	struct dm_writecache *wc = ti->private;
+	enum wc_map_op map_op = WC_MAP_ERROR;
 
 	bio->bi_private = NULL;
 
@@ -1342,167 +1496,49 @@ static int writecache_map(struct dm_target *ti, struct bio *bio)
 		}
 	}
 
-	if (bio_data_dir(bio) == READ) {
-read_next_block:
-		e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING);
-		if (e && read_original_sector(wc, e) == bio->bi_iter.bi_sector) {
-			if (WC_MODE_PMEM(wc)) {
-				bio_copy_block(wc, bio, memory_data(wc, e));
-				if (bio->bi_iter.bi_size)
-					goto read_next_block;
-				goto unlock_submit;
-			} else {
-				dm_accept_partial_bio(bio, wc->block_size >> SECTOR_SHIFT);
-				bio_set_dev(bio, wc->ssd_dev->bdev);
-				bio->bi_iter.bi_sector = cache_sector(wc, e);
-				if (!writecache_entry_is_committed(wc, e))
-					writecache_wait_for_ios(wc, WRITE);
-				goto unlock_remap;
-			}
-		} else {
-			if (e) {
-				sector_t next_boundary =
-					read_original_sector(wc, e) - bio->bi_iter.bi_sector;
-				if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT) {
-					dm_accept_partial_bio(bio, next_boundary);
-				}
-			}
-			goto unlock_remap_origin;
-		}
-	} else {
-		do {
-			bool found_entry = false;
-			bool search_used = false;
-			if (writecache_has_error(wc))
-				goto unlock_error;
-			e = writecache_find_entry(wc, bio->bi_iter.bi_sector, 0);
-			if (e) {
-				if (!writecache_entry_is_committed(wc, e)) {
-					search_used = true;
-					goto bio_copy;
-				}
-				if (!WC_MODE_PMEM(wc) && !e->write_in_progress) {
-					wc->overwrote_committed = true;
-					search_used = true;
-					goto bio_copy;
-				}
-				found_entry = true;
-			} else {
-				if (unlikely(wc->cleaner) ||
-				    (wc->metadata_only && !(bio->bi_opf & REQ_META)))
-					goto direct_write;
-			}
-			e = writecache_pop_from_freelist(wc, (sector_t)-1);
-			if (unlikely(!e)) {
-				if (!WC_MODE_PMEM(wc) && !found_entry) {
-direct_write:
-					e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING);
-					if (e) {
-						sector_t next_boundary = read_original_sector(wc, e) - bio->bi_iter.bi_sector;
-						BUG_ON(!next_boundary);
-						if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT) {
-							dm_accept_partial_bio(bio, next_boundary);
-						}
-					}
-					goto unlock_remap_origin;
-				}
-				writecache_wait_on_freelist(wc);
-				continue;
-			}
-			write_original_sector_seq_count(wc, e, bio->bi_iter.bi_sector, wc->seq_count);
-			writecache_insert_entry(wc, e);
-			wc->uncommitted_blocks++;
-bio_copy:
-			if (WC_MODE_PMEM(wc)) {
-				bio_copy_block(wc, bio, memory_data(wc, e));
-			} else {
-				unsigned bio_size = wc->block_size;
-				sector_t start_cache_sec = cache_sector(wc, e);
-				sector_t current_cache_sec = start_cache_sec + (bio_size >> SECTOR_SHIFT);
-
-				while (bio_size < bio->bi_iter.bi_size) {
-					if (!search_used) {
-						struct wc_entry *f = writecache_pop_from_freelist(wc, current_cache_sec);
-						if (!f)
-							break;
-						write_original_sector_seq_count(wc, f, bio->bi_iter.bi_sector +
-										(bio_size >> SECTOR_SHIFT), wc->seq_count);
-						writecache_insert_entry(wc, f);
-						wc->uncommitted_blocks++;
-					} else {
-						struct wc_entry *f;
-						struct rb_node *next = rb_next(&e->rb_node);
-						if (!next)
-							break;
-						f = container_of(next, struct wc_entry, rb_node);
-						if (f != e + 1)
-							break;
-						if (read_original_sector(wc, f) !=
-						    read_original_sector(wc, e) + (wc->block_size >> SECTOR_SHIFT))
-							break;
-						if (unlikely(f->write_in_progress))
-							break;
-						if (writecache_entry_is_committed(wc, f))
-							wc->overwrote_committed = true;
-						e = f;
-					}
-					bio_size += wc->block_size;
-					current_cache_sec += wc->block_size >> SECTOR_SHIFT;
-				}
-
-				bio_set_dev(bio, wc->ssd_dev->bdev);
-				bio->bi_iter.bi_sector = start_cache_sec;
-				dm_accept_partial_bio(bio, bio_size >> SECTOR_SHIFT);
-
-				if (unlikely(wc->uncommitted_blocks >= wc->autocommit_blocks)) {
-					wc->uncommitted_blocks = 0;
-					queue_work(wc->writeback_wq, &wc->flush_work);
-				} else {
-					writecache_schedule_autocommit(wc);
-				}
-				goto unlock_remap;
-			}
-		} while (bio->bi_iter.bi_size);
-
-		if (unlikely(bio->bi_opf & REQ_FUA ||
-			     wc->uncommitted_blocks >= wc->autocommit_blocks))
-			writecache_flush(wc);
-		else
-			writecache_schedule_autocommit(wc);
-		goto unlock_submit;
-	}
+	if (bio_data_dir(bio) == READ)
+		map_op = writecache_map_read(wc, bio);
+	else
+		map_op = writecache_map_write(wc, bio);
 
+	switch (map_op) {
+	case WC_MAP_REMAP_ORIGIN:
 unlock_remap_origin:
-	if (likely(wc->pause != 0)) {
-		 if (bio_op(bio) == REQ_OP_WRITE) {
-			dm_iot_io_begin(&wc->iot, 1);
-			bio->bi_private = (void *)2;
+		if (likely(wc->pause != 0)) {
+			if (bio_op(bio) == REQ_OP_WRITE) {
+				dm_iot_io_begin(&wc->iot, 1);
+				bio->bi_private = (void *)2;
+			}
 		}
-	}
-	bio_set_dev(bio, wc->dev->bdev);
-	wc_unlock(wc);
-	return DM_MAPIO_REMAPPED;
+		bio_set_dev(bio, wc->dev->bdev);
+		wc_unlock(wc);
+		return DM_MAPIO_REMAPPED;
 
+	case WC_MAP_REMAP:
 unlock_remap:
-	/* make sure that writecache_end_io decrements bio_in_progress: */
-	bio->bi_private = (void *)1;
-	atomic_inc(&wc->bio_in_progress[bio_data_dir(bio)]);
-	wc_unlock(wc);
-	return DM_MAPIO_REMAPPED;
+		/* make sure that writecache_end_io decrements bio_in_progress: */
+		bio->bi_private = (void *)1;
+		atomic_inc(&wc->bio_in_progress[bio_data_dir(bio)]);
+		wc_unlock(wc);
+		return DM_MAPIO_REMAPPED;
 
+	case WC_MAP_SUBMIT:
 unlock_submit:
-	wc_unlock(wc);
-	bio_endio(bio);
-	return DM_MAPIO_SUBMITTED;
+		wc_unlock(wc);
+		bio_endio(bio);
+		return DM_MAPIO_SUBMITTED;
 
+	case WC_MAP_RETURN:
 unlock_return:
-	wc_unlock(wc);
-	return DM_MAPIO_SUBMITTED;
+		wc_unlock(wc);
+		return DM_MAPIO_SUBMITTED;
 
+	case WC_MAP_ERROR:
 unlock_error:
-	wc_unlock(wc);
-	bio_io_error(bio);
-	return DM_MAPIO_SUBMITTED;
+		wc_unlock(wc);
+		bio_io_error(bio);
+		return DM_MAPIO_SUBMITTED;
+	}
 }
 
 static int writecache_end_io(struct dm_target *ti, struct bio *bio, blk_status_t *status)
-- 
cgit v1.2.3


From 4d020b3a290707b19a3974fe8bc356f0b01b6928 Mon Sep 17 00:00:00 2001
From: Mike Snitzer <snitzer@redhat.com>
Date: Mon, 12 Jul 2021 16:58:49 -0400
Subject: dm writecache: factor out writecache_map_remap_origin()

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-writecache.c | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 53076c7f4a34..2a920e95975a 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -1301,6 +1301,19 @@ enum wc_map_op {
 	WC_MAP_ERROR,
 };
 
+static enum wc_map_op writecache_map_remap_origin(struct dm_writecache *wc, struct bio *bio,
+						  struct wc_entry *e)
+{
+	if (e) {
+		sector_t next_boundary =
+			read_original_sector(wc, e) - bio->bi_iter.bi_sector;
+		if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT)
+			dm_accept_partial_bio(bio, next_boundary);
+	}
+
+	return WC_MAP_REMAP_ORIGIN;
+}
+
 static enum wc_map_op writecache_map_read(struct dm_writecache *wc, struct bio *bio)
 {
 	enum wc_map_op map_op;
@@ -1323,13 +1336,7 @@ read_next_block:
 			map_op = WC_MAP_REMAP;
 		}
 	} else {
-		if (e) {
-			sector_t next_boundary =
-				read_original_sector(wc, e) - bio->bi_iter.bi_sector;
-			if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT)
-				dm_accept_partial_bio(bio, next_boundary);
-		}
-		map_op = WC_MAP_REMAP_ORIGIN;
+		map_op = writecache_map_remap_origin(wc, bio, e);
 	}
 
 	return map_op;
@@ -1417,14 +1424,7 @@ static enum wc_map_op writecache_map_write(struct dm_writecache *wc, struct bio
 			if (!WC_MODE_PMEM(wc) && !found_entry) {
 direct_write:
 				e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING);
-				if (e) {
-					sector_t next_boundary = read_original_sector(wc, e) - bio->bi_iter.bi_sector;
-					BUG_ON(!next_boundary);
-					if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT) {
-						dm_accept_partial_bio(bio, next_boundary);
-					}
-				}
-				return WC_MAP_REMAP_ORIGIN;
+				return writecache_map_remap_origin(wc, bio, e);
 			}
 			writecache_wait_on_freelist(wc);
 			continue;
-- 
cgit v1.2.3


From 15cb6f39dbaf391dd3b70389c2882df998d5189a Mon Sep 17 00:00:00 2001
From: Mike Snitzer <snitzer@redhat.com>
Date: Mon, 12 Jul 2021 21:21:34 -0400
Subject: dm writecache: further writecache_map() cleanup

Factor out writecache_map_flush() and writecache_map_discard() from
writecache_map(). Also eliminate the various goto labels in
writecache_map().

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-writecache.c | 75 ++++++++++++++++++++++++++--------------------
 1 file changed, 43 insertions(+), 32 deletions(-)

diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 2a920e95975a..64d7a798244a 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -1447,31 +1447,52 @@ bio_copy:
 	return WC_MAP_SUBMIT;
 }
 
+static enum wc_map_op writecache_map_flush(struct dm_writecache *wc, struct bio *bio)
+{
+	if (writecache_has_error(wc))
+		return WC_MAP_ERROR;
+
+	if (WC_MODE_PMEM(wc)) {
+		writecache_flush(wc);
+		if (writecache_has_error(wc))
+			return WC_MAP_ERROR;
+		else if (unlikely(wc->cleaner) || unlikely(wc->metadata_only))
+			return WC_MAP_REMAP_ORIGIN;
+		return WC_MAP_SUBMIT;
+	}
+	/* SSD: */
+	if (dm_bio_get_target_bio_nr(bio))
+		return WC_MAP_REMAP_ORIGIN;
+	writecache_offload_bio(wc, bio);
+	return WC_MAP_RETURN;
+}
+
+static enum wc_map_op writecache_map_discard(struct dm_writecache *wc, struct bio *bio)
+{
+	if (writecache_has_error(wc))
+		return WC_MAP_ERROR;
+
+	if (WC_MODE_PMEM(wc)) {
+		writecache_discard(wc, bio->bi_iter.bi_sector, bio_end_sector(bio));
+		return WC_MAP_REMAP_ORIGIN;
+	}
+	/* SSD: */
+	writecache_offload_bio(wc, bio);
+	return WC_MAP_RETURN;
+}
+
 static int writecache_map(struct dm_target *ti, struct bio *bio)
 {
 	struct dm_writecache *wc = ti->private;
-	enum wc_map_op map_op = WC_MAP_ERROR;
+	enum wc_map_op map_op;
 
 	bio->bi_private = NULL;
 
 	wc_lock(wc);
 
 	if (unlikely(bio->bi_opf & REQ_PREFLUSH)) {
-		if (writecache_has_error(wc))
-			goto unlock_error;
-		if (WC_MODE_PMEM(wc)) {
-			writecache_flush(wc);
-			if (writecache_has_error(wc))
-				goto unlock_error;
-			if (unlikely(wc->cleaner) || unlikely(wc->metadata_only))
-				goto unlock_remap_origin;
-			goto unlock_submit;
-		} else {
-			if (dm_bio_get_target_bio_nr(bio))
-				goto unlock_remap_origin;
-			writecache_offload_bio(wc, bio);
-			goto unlock_return;
-		}
+		map_op = writecache_map_flush(wc, bio);
+		goto done;
 	}
 
 	bio->bi_iter.bi_sector = dm_target_offset(ti, bio->bi_iter.bi_sector);
@@ -1481,29 +1502,22 @@ static int writecache_map(struct dm_target *ti, struct bio *bio)
 		DMERR("I/O is not aligned, sector %llu, size %u, block size %u",
 		      (unsigned long long)bio->bi_iter.bi_sector,
 		      bio->bi_iter.bi_size, wc->block_size);
-		goto unlock_error;
+		map_op = WC_MAP_ERROR;
+		goto done;
 	}
 
 	if (unlikely(bio_op(bio) == REQ_OP_DISCARD)) {
-		if (writecache_has_error(wc))
-			goto unlock_error;
-		if (WC_MODE_PMEM(wc)) {
-			writecache_discard(wc, bio->bi_iter.bi_sector, bio_end_sector(bio));
-			goto unlock_remap_origin;
-		} else {
-			writecache_offload_bio(wc, bio);
-			goto unlock_return;
-		}
+		map_op = writecache_map_discard(wc, bio);
+		goto done;
 	}
 
 	if (bio_data_dir(bio) == READ)
 		map_op = writecache_map_read(wc, bio);
 	else
 		map_op = writecache_map_write(wc, bio);
-
+done:
 	switch (map_op) {
 	case WC_MAP_REMAP_ORIGIN:
-unlock_remap_origin:
 		if (likely(wc->pause != 0)) {
 			if (bio_op(bio) == REQ_OP_WRITE) {
 				dm_iot_io_begin(&wc->iot, 1);
@@ -1515,7 +1529,6 @@ unlock_remap_origin:
 		return DM_MAPIO_REMAPPED;
 
 	case WC_MAP_REMAP:
-unlock_remap:
 		/* make sure that writecache_end_io decrements bio_in_progress: */
 		bio->bi_private = (void *)1;
 		atomic_inc(&wc->bio_in_progress[bio_data_dir(bio)]);
@@ -1523,18 +1536,16 @@ unlock_remap:
 		return DM_MAPIO_REMAPPED;
 
 	case WC_MAP_SUBMIT:
-unlock_submit:
 		wc_unlock(wc);
 		bio_endio(bio);
 		return DM_MAPIO_SUBMITTED;
 
 	case WC_MAP_RETURN:
-unlock_return:
 		wc_unlock(wc);
 		return DM_MAPIO_SUBMITTED;
 
 	case WC_MAP_ERROR:
-unlock_error:
+	default:
 		wc_unlock(wc);
 		bio_io_error(bio);
 		return DM_MAPIO_SUBMITTED;
-- 
cgit v1.2.3


From df699cc16ea5ef93a917676dcdd4376e02860ad5 Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@redhat.com>
Date: Tue, 27 Jul 2021 09:45:13 -0400
Subject: dm writecache: report invalid return from writecache_map helpers

If some "writecache_map_*" function returns invalid state, it is a bug.
So, we should report it and not fail silently.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-writecache.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 64d7a798244a..e89868cf7d98 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -1545,10 +1545,13 @@ done:
 		return DM_MAPIO_SUBMITTED;
 
 	case WC_MAP_ERROR:
-	default:
 		wc_unlock(wc);
 		bio_io_error(bio);
 		return DM_MAPIO_SUBMITTED;
+
+	default:
+		BUG();
+		return -1;
 	}
 }
 
-- 
cgit v1.2.3


From e3a35d03407cb3ef9488835aa861e07b45638d0b Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@redhat.com>
Date: Tue, 27 Jul 2021 09:42:21 -0400
Subject: dm writecache: add event counters

Add 10 counters for various events (hit, miss, etc) and export them in
the status line (accessed from userspace with "dmsetup status"). Also
add a message "clear_stats" that resets these counters.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 .../admin-guide/device-mapper/writecache.rst       | 16 ++++++-
 drivers/md/dm-writecache.c                         | 56 ++++++++++++++++++++--
 2 files changed, 67 insertions(+), 5 deletions(-)

diff --git a/Documentation/admin-guide/device-mapper/writecache.rst b/Documentation/admin-guide/device-mapper/writecache.rst
index 65427d8dfca6..10429779a91a 100644
--- a/Documentation/admin-guide/device-mapper/writecache.rst
+++ b/Documentation/admin-guide/device-mapper/writecache.rst
@@ -78,13 +78,23 @@ Status:
 2. the number of blocks
 3. the number of free blocks
 4. the number of blocks under writeback
+5. the number of read requests
+6. the number of read requests that hit the cache
+7. the number of write requests
+8. the number of write requests that hit uncommitted block
+9. the number of write requests that hit committed block
+10. the number of write requests that bypass the cache
+11. the number of write requests that are allocated in the cache
+12. the number of write requests that are blocked on the freelist
+13. the number of flush requests
+14. the number of discard requests
 
 Messages:
 	flush
-		flush the cache device. The message returns successfully
+		Flush the cache device. The message returns successfully
 		if the cache device was flushed without an error
 	flush_on_suspend
-		flush the cache device on next suspend. Use this message
+		Flush the cache device on next suspend. Use this message
 		when you are going to remove the cache device. The proper
 		sequence for removing the cache device is:
 
@@ -98,3 +108,5 @@ Messages:
 		6. the cache device is now inactive and it can be deleted
 	cleaner
 		See above "cleaner" constructor documentation.
+	clear_stats
+		Clear the statistics that are reported on the status line
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index e89868cf7d98..e1d7234eec3f 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -206,6 +206,19 @@ struct dm_writecache {
 
 	struct bio_set bio_set;
 	mempool_t copy_pool;
+
+	struct {
+		unsigned long long reads;
+		unsigned long long read_hits;
+		unsigned long long writes;
+		unsigned long long write_hits_uncommitted;
+		unsigned long long write_hits_committed;
+		unsigned long long writes_around;
+		unsigned long long writes_allocate;
+		unsigned long long writes_blocked_on_freelist;
+		unsigned long long flushes;
+		unsigned long long discards;
+	} stats;
 };
 
 #define WB_LIST_INLINE		16
@@ -1157,6 +1170,18 @@ static int process_cleaner_mesg(unsigned argc, char **argv, struct dm_writecache
 	return 0;
 }
 
+static int process_clear_stats_mesg(unsigned argc, char **argv, struct dm_writecache *wc)
+{
+	if (argc != 1)
+		return -EINVAL;
+
+	wc_lock(wc);
+	memset(&wc->stats, 0, sizeof wc->stats);
+	wc_unlock(wc);
+
+	return 0;
+}
+
 static int writecache_message(struct dm_target *ti, unsigned argc, char **argv,
 			      char *result, unsigned maxlen)
 {
@@ -1169,6 +1194,8 @@ static int writecache_message(struct dm_target *ti, unsigned argc, char **argv,
 		r = process_flush_on_suspend_mesg(argc, argv, wc);
 	else if (!strcasecmp(argv[0], "cleaner"))
 		r = process_cleaner_mesg(argc, argv, wc);
+	else if (!strcasecmp(argv[0], "clear_stats"))
+		r = process_clear_stats_mesg(argc, argv, wc);
 	else
 		DMERR("unrecognised message received: %s", argv[0]);
 
@@ -1320,8 +1347,10 @@ static enum wc_map_op writecache_map_read(struct dm_writecache *wc, struct bio *
 	struct wc_entry *e;
 
 read_next_block:
+	wc->stats.reads++;
 	e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING);
 	if (e && read_original_sector(wc, e) == bio->bi_iter.bi_sector) {
+		wc->stats.read_hits++;
 		if (WC_MODE_PMEM(wc)) {
 			bio_copy_block(wc, bio, memory_data(wc, e));
 			if (bio->bi_iter.bi_size)
@@ -1400,14 +1429,17 @@ static enum wc_map_op writecache_map_write(struct dm_writecache *wc, struct bio
 	do {
 		bool found_entry = false;
 		bool search_used = false;
+		wc->stats.writes++;
 		if (writecache_has_error(wc))
 			return WC_MAP_ERROR;
 		e = writecache_find_entry(wc, bio->bi_iter.bi_sector, 0);
 		if (e) {
 			if (!writecache_entry_is_committed(wc, e)) {
+				wc->stats.write_hits_uncommitted++;
 				search_used = true;
 				goto bio_copy;
 			}
+			wc->stats.write_hits_committed++;
 			if (!WC_MODE_PMEM(wc) && !e->write_in_progress) {
 				wc->overwrote_committed = true;
 				search_used = true;
@@ -1423,15 +1455,18 @@ static enum wc_map_op writecache_map_write(struct dm_writecache *wc, struct bio
 		if (unlikely(!e)) {
 			if (!WC_MODE_PMEM(wc) && !found_entry) {
 direct_write:
+				wc->stats.writes_around++;
 				e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING);
 				return writecache_map_remap_origin(wc, bio, e);
 			}
+			wc->stats.writes_blocked_on_freelist++;
 			writecache_wait_on_freelist(wc);
 			continue;
 		}
 		write_original_sector_seq_count(wc, e, bio->bi_iter.bi_sector, wc->seq_count);
 		writecache_insert_entry(wc, e);
 		wc->uncommitted_blocks++;
+		wc->stats.writes_allocate++;
 bio_copy:
 		if (WC_MODE_PMEM(wc))
 			bio_copy_block(wc, bio, memory_data(wc, e));
@@ -1453,6 +1488,7 @@ static enum wc_map_op writecache_map_flush(struct dm_writecache *wc, struct bio
 		return WC_MAP_ERROR;
 
 	if (WC_MODE_PMEM(wc)) {
+		wc->stats.flushes++;
 		writecache_flush(wc);
 		if (writecache_has_error(wc))
 			return WC_MAP_ERROR;
@@ -1463,12 +1499,15 @@ static enum wc_map_op writecache_map_flush(struct dm_writecache *wc, struct bio
 	/* SSD: */
 	if (dm_bio_get_target_bio_nr(bio))
 		return WC_MAP_REMAP_ORIGIN;
+	wc->stats.flushes++;
 	writecache_offload_bio(wc, bio);
 	return WC_MAP_RETURN;
 }
 
 static enum wc_map_op writecache_map_discard(struct dm_writecache *wc, struct bio *bio)
 {
+	wc->stats.discards++;
+
 	if (writecache_has_error(wc))
 		return WC_MAP_ERROR;
 
@@ -2618,9 +2657,20 @@ static void writecache_status(struct dm_target *ti, status_type_t type,
 
 	switch (type) {
 	case STATUSTYPE_INFO:
-		DMEMIT("%ld %llu %llu %llu", writecache_has_error(wc),
+		DMEMIT("%ld %llu %llu %llu %llu %llu %llu %llu %llu %llu %llu %llu %llu %llu",
+		       writecache_has_error(wc),
 		       (unsigned long long)wc->n_blocks, (unsigned long long)wc->freelist_size,
-		       (unsigned long long)wc->writeback_size);
+		       (unsigned long long)wc->writeback_size,
+		       wc->stats.reads,
+		       wc->stats.read_hits,
+		       wc->stats.writes,
+		       wc->stats.write_hits_uncommitted,
+		       wc->stats.write_hits_committed,
+		       wc->stats.writes_around,
+		       wc->stats.writes_allocate,
+		       wc->stats.writes_blocked_on_freelist,
+		       wc->stats.flushes,
+		       wc->stats.discards);
 		break;
 	case STATUSTYPE_TABLE:
 		DMEMIT("%c %s %s %u ", WC_MODE_PMEM(wc) ? 'p' : 's',
@@ -2678,7 +2728,7 @@ static void writecache_status(struct dm_target *ti, status_type_t type,
 
 static struct target_type writecache_target = {
 	.name			= "writecache",
-	.version		= {1, 5, 0},
+	.version		= {1, 6, 0},
 	.module			= THIS_MODULE,
 	.ctr			= writecache_ctr,
 	.dtr			= writecache_dtr,
-- 
cgit v1.2.3


From 91ccbbac1747eea155632a1c6bb100052309b215 Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Mon, 12 Jul 2021 17:48:58 -0700
Subject: dm ima: measure data on table load
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

DM configures a block device with various target specific attributes
passed to it as a table.  DM loads the table, and calls each target’s
respective constructors with the attributes as input parameters.
Some of these attributes are critical to ensure the device meets
certain security bar.  Thus, IMA should measure these attributes, to
ensure they are not tampered with, during the lifetime of the device.
So that the external services can have high confidence in the
configuration of the block-devices on a given system.

Some devices may have large tables.  And a given device may change its
state (table-load, suspend, resume, rename, remove, table-clear etc.)
many times.  Measuring these attributes each time when the device
changes its state will significantly increase the size of the IMA logs.
Further, once configured, these attributes are not expected to change
unless a new table is loaded, or a device is removed and recreated.
Therefore the clear-text of the attributes should only be measured
during table load, and the hash of the active/inactive table should be
measured for the remaining device state changes.

Export IMA function ima_measure_critical_data() to allow measurement
of DM device parameters, as well as target specific attributes, during
table load.  Compute the hash of the inactive table and store it for
measurements during future state change.  If a load is called multiple
times, update the inactive table hash with the hash of the latest
populated table.  So that the correct inactive table hash is measured
when the device transitions to different states like resume, remove,
rename, etc.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com> # leak fix
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/Makefile               |   4 +
 drivers/md/dm-core.h              |   5 +
 drivers/md/dm-ima.c               | 330 ++++++++++++++++++++++++++++++++++++++
 drivers/md/dm-ima.h               |  59 +++++++
 drivers/md/dm-ioctl.c             |   7 +-
 drivers/md/dm.c                   |   3 +
 include/linux/device-mapper.h     |   2 +-
 include/uapi/linux/dm-ioctl.h     |   6 +
 security/integrity/ima/ima_main.c |   1 +
 9 files changed, 415 insertions(+), 2 deletions(-)
 create mode 100644 drivers/md/dm-ima.c
 create mode 100644 drivers/md/dm-ima.h

diff --git a/drivers/md/Makefile b/drivers/md/Makefile
index a74aaf8b1445..816945eeed7f 100644
--- a/drivers/md/Makefile
+++ b/drivers/md/Makefile
@@ -96,6 +96,10 @@ ifeq ($(CONFIG_BLK_DEV_ZONED),y)
 dm-mod-objs			+= dm-zone.o
 endif
 
+ifeq ($(CONFIG_IMA),y)
+dm-mod-objs			+= dm-ima.o
+endif
+
 ifeq ($(CONFIG_DM_VERITY_FEC),y)
 dm-verity-objs			+= dm-verity-fec.o
 endif
diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h
index edc1553c4eea..55dccdfbcb22 100644
--- a/drivers/md/dm-core.h
+++ b/drivers/md/dm-core.h
@@ -18,6 +18,7 @@
 #include <trace/events/block.h>
 
 #include "dm.h"
+#include "dm-ima.h"
 
 #define DM_RESERVED_MAX_IOS		1024
 
@@ -119,6 +120,10 @@ struct mapped_device {
 	unsigned int nr_zones;
 	unsigned int *zwp_offset;
 #endif
+
+#ifdef CONFIG_IMA
+	struct dm_ima_measurements ima;
+#endif
 };
 
 /*
diff --git a/drivers/md/dm-ima.c b/drivers/md/dm-ima.c
new file mode 100644
index 000000000000..c8f54d9f6c8d
--- /dev/null
+++ b/drivers/md/dm-ima.c
@@ -0,0 +1,330 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 Microsoft Corporation
+ *
+ * Author: Tushar Sugandhi <tusharsu@linux.microsoft.com>
+ *
+ * File: dm-ima.c
+ *       Enables IMA measurements for DM targets
+ */
+
+#include "dm-core.h"
+#include "dm-ima.h"
+
+#include <linux/ima.h>
+#include <crypto/hash.h>
+#include <linux/crypto.h>
+#include <crypto/hash_info.h>
+
+#define DM_MSG_PREFIX "ima"
+
+/*
+ * Internal function to prefix separator characters in input buffer with escape
+ * character, so that they don't interfere with the construction of key-value pairs,
+ * and clients can split the key1=val1,key2=val2,key3=val3; pairs properly.
+ */
+static void fix_separator_chars(char **buf)
+{
+	int l = strlen(*buf);
+	int i, j, sp = 0;
+
+	for (i = 0; i < l; i++)
+		if ((*buf)[i] == '\\' || (*buf)[i] == ';' || (*buf)[i] == '=' || (*buf)[i] == ',')
+			sp++;
+
+	if (!sp)
+		return;
+
+	for (i = l-1, j = i+sp; i >= 0; i--) {
+		(*buf)[j--] = (*buf)[i];
+		if ((*buf)[i] == '\\' || (*buf)[i] == ';' || (*buf)[i] == '=' || (*buf)[i] == ',')
+			(*buf)[j--] = '\\';
+	}
+}
+
+/*
+ * Internal function to allocate memory for IMA measurements.
+ */
+static void *dm_ima_alloc(size_t len, gfp_t flags, bool noio)
+{
+	unsigned int noio_flag;
+	void *ptr;
+
+	if (noio)
+		noio_flag = memalloc_noio_save();
+
+	ptr = kzalloc(len, flags);
+
+	if (noio)
+		memalloc_noio_restore(noio_flag);
+
+	return ptr;
+}
+
+/*
+ * Internal function to allocate and copy name and uuid for IMA measurements.
+ */
+static int dm_ima_alloc_and_copy_name_uuid(struct mapped_device *md, char **dev_name,
+					   char **dev_uuid, bool noio)
+{
+	int r;
+	*dev_name = dm_ima_alloc(DM_NAME_LEN*2, GFP_KERNEL, noio);
+	if (!(*dev_name)) {
+		r = -ENOMEM;
+		goto error;
+	}
+
+	*dev_uuid = dm_ima_alloc(DM_UUID_LEN*2, GFP_KERNEL, noio);
+	if (!(*dev_uuid)) {
+		r = -ENOMEM;
+		goto error;
+	}
+
+	r = dm_copy_name_and_uuid(md, *dev_name, *dev_uuid);
+	if (r)
+		goto error;
+
+	fix_separator_chars(dev_name);
+	fix_separator_chars(dev_uuid);
+
+	return 0;
+error:
+	kfree(*dev_name);
+	kfree(*dev_uuid);
+	*dev_name = NULL;
+	*dev_uuid = NULL;
+	return r;
+}
+
+/*
+ * Internal function to allocate and copy device data for IMA measurements.
+ */
+static int dm_ima_alloc_and_copy_device_data(struct mapped_device *md, char **device_data,
+					     unsigned int num_targets, bool noio)
+{
+	char *dev_name = NULL, *dev_uuid = NULL;
+	int r;
+
+	r = dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio);
+	if (r)
+		return r;
+
+	*device_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
+	if (!(*device_data)) {
+		r = -ENOMEM;
+		goto error;
+	}
+
+	scnprintf(*device_data, DM_IMA_DEVICE_BUF_LEN,
+		  "name=%s,uuid=%s,major=%d,minor=%d,minor_count=%d,num_targets=%u;",
+		  dev_name, dev_uuid, md->disk->major, md->disk->first_minor,
+		  md->disk->minors, num_targets);
+error:
+	kfree(dev_name);
+	kfree(dev_uuid);
+	return r;
+}
+
+/*
+ * Internal wrapper function to call IMA to measure DM data.
+ */
+static void dm_ima_measure_data(const char *event_name, const void *buf, size_t buf_len,
+				bool noio)
+{
+	unsigned int noio_flag;
+
+	if (noio)
+		noio_flag = memalloc_noio_save();
+
+	ima_measure_critical_data(DM_NAME, event_name, buf, buf_len, false);
+
+	if (noio)
+		memalloc_noio_restore(noio_flag);
+}
+
+/*
+ * Initialize/reset the dm ima related data structure variables.
+ */
+void dm_ima_reset_data(struct mapped_device *md)
+{
+	memset(&(md->ima), 0, sizeof(md->ima));
+}
+
+/*
+ * Build up the IMA data for each target, and finally measure.
+ */
+void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags)
+{
+	size_t device_data_buf_len, target_metadata_buf_len, target_data_buf_len, l = 0;
+	char *target_metadata_buf = NULL, *target_data_buf = NULL, *digest_buf = NULL;
+	char *ima_buf = NULL, *device_data_buf = NULL;
+	int digest_size, last_target_measured = -1, r;
+	status_type_t type = STATUSTYPE_IMA;
+	size_t cur_total_buf_len = 0;
+	unsigned int num_targets, i;
+	SHASH_DESC_ON_STACK(shash, NULL);
+	struct crypto_shash *tfm = NULL;
+	u8 *digest = NULL;
+	bool noio = false;
+
+	ima_buf = dm_ima_alloc(DM_IMA_MEASUREMENT_BUF_LEN, GFP_KERNEL, noio);
+	if (!ima_buf)
+		return;
+
+	target_metadata_buf = dm_ima_alloc(DM_IMA_TARGET_METADATA_BUF_LEN, GFP_KERNEL, noio);
+	if (!target_metadata_buf)
+		goto error;
+
+	target_data_buf = dm_ima_alloc(DM_IMA_TARGET_DATA_BUF_LEN, GFP_KERNEL, noio);
+	if (!target_data_buf)
+		goto error;
+
+	num_targets = dm_table_get_num_targets(table);
+
+	if (dm_ima_alloc_and_copy_device_data(table->md, &device_data_buf, num_targets, noio))
+		goto error;
+
+	tfm = crypto_alloc_shash("sha256", 0, 0);
+	if (IS_ERR(tfm))
+		goto error;
+
+	shash->tfm = tfm;
+	digest_size = crypto_shash_digestsize(tfm);
+	digest = dm_ima_alloc(digest_size, GFP_KERNEL, noio);
+	if (!digest)
+		goto error;
+
+	r = crypto_shash_init(shash);
+	if (r)
+		goto error;
+
+	device_data_buf_len = strlen(device_data_buf);
+	memcpy(ima_buf + l, device_data_buf, device_data_buf_len);
+	l += device_data_buf_len;
+
+	for (i = 0; i < num_targets; i++) {
+		struct dm_target *ti = dm_table_get_target(table, i);
+
+		if (!ti)
+			goto error;
+
+		last_target_measured = 0;
+
+		/*
+		 * First retrieve the target metadata.
+		 */
+		scnprintf(target_metadata_buf, DM_IMA_TARGET_METADATA_BUF_LEN,
+			  "target_index=%d,target_begin=%llu,target_len=%llu,",
+			  i, ti->begin, ti->len);
+		target_metadata_buf_len = strlen(target_metadata_buf);
+
+		/*
+		 * Then retrieve the actual target data.
+		 */
+		if (ti->type->status)
+			ti->type->status(ti, type, status_flags, target_data_buf,
+					 DM_IMA_TARGET_DATA_BUF_LEN);
+		else
+			target_data_buf[0] = '\0';
+
+		target_data_buf_len = strlen(target_data_buf);
+
+		/*
+		 * Check if the total data can fit into the IMA buffer.
+		 */
+		cur_total_buf_len = l + target_metadata_buf_len + target_data_buf_len;
+
+		/*
+		 * IMA measurements for DM targets are best-effort.
+		 * If the total data buffered so far, including the current target,
+		 * is too large to fit into DM_IMA_MEASUREMENT_BUF_LEN, measure what
+		 * we have in the current buffer, and continue measuring the remaining
+		 * targets by prefixing the device metadata again.
+		 */
+		if (unlikely(cur_total_buf_len >= DM_IMA_MEASUREMENT_BUF_LEN)) {
+			dm_ima_measure_data("table_load", ima_buf, l, noio);
+			r = crypto_shash_update(shash, (const u8 *)ima_buf, l);
+			if (r < 0)
+				goto error;
+
+			memset(ima_buf, 0, DM_IMA_MEASUREMENT_BUF_LEN);
+			l = 0;
+
+			/*
+			 * Each new "table_load" entry in IMA log should have device data
+			 * prefix, so that multiple records from the same table_load for
+			 * a given device can be linked together.
+			 */
+			memcpy(ima_buf + l, device_data_buf, device_data_buf_len);
+			l += device_data_buf_len;
+
+			/*
+			 * If this iteration of the for loop turns out to be the last target
+			 * in the table, dm_ima_measure_data("table_load", ...) doesn't need
+			 * to be called again, just the hash needs to be finalized.
+			 * "last_target_measured" tracks this state.
+			 */
+			last_target_measured = 1;
+		}
+
+		/*
+		 * Fill-in all the target metadata, so that multiple targets for the same
+		 * device can be linked together.
+		 */
+		memcpy(ima_buf + l, target_metadata_buf, target_metadata_buf_len);
+		l += target_metadata_buf_len;
+
+		memcpy(ima_buf + l, target_data_buf, target_data_buf_len);
+		l += target_data_buf_len;
+	}
+
+	if (!last_target_measured) {
+		dm_ima_measure_data("table_load", ima_buf, l, noio);
+
+		r = crypto_shash_update(shash, (const u8 *)ima_buf, l);
+		if (r < 0)
+			goto error;
+	}
+
+	/*
+	 * Finalize the table hash, and store it in table->md->ima.inactive_table.hash,
+	 * so that the table data can be verified against the future device state change
+	 * events, e.g. resume, rename, remove, table-clear etc.
+	 */
+	r = crypto_shash_final(shash, digest);
+	if (r < 0)
+		goto error;
+
+	digest_buf = dm_ima_alloc((digest_size*2)+1, GFP_KERNEL, noio);
+	if (!digest_buf)
+		goto error;
+
+	for (i = 0; i < digest_size; i++)
+		snprintf((digest_buf+(i*2)), 3, "%02x", digest[i]);
+
+	if (table->md->ima.active_table.hash != table->md->ima.inactive_table.hash)
+		kfree(table->md->ima.inactive_table.hash);
+
+	table->md->ima.inactive_table.hash = digest_buf;
+	table->md->ima.inactive_table.hash_len = strlen(digest_buf);
+	table->md->ima.inactive_table.num_targets = num_targets;
+
+	if (table->md->ima.active_table.device_metadata !=
+	    table->md->ima.inactive_table.device_metadata)
+		kfree(table->md->ima.inactive_table.device_metadata);
+
+	table->md->ima.inactive_table.device_metadata = device_data_buf;
+	table->md->ima.inactive_table.device_metadata_len = device_data_buf_len;
+
+	goto exit;
+error:
+	kfree(digest_buf);
+	kfree(device_data_buf);
+exit:
+	kfree(digest);
+	if (tfm)
+		crypto_free_shash(tfm);
+	kfree(ima_buf);
+	kfree(target_metadata_buf);
+	kfree(target_data_buf);
+}
diff --git a/drivers/md/dm-ima.h b/drivers/md/dm-ima.h
new file mode 100644
index 000000000000..16afd9a8c0b2
--- /dev/null
+++ b/drivers/md/dm-ima.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (C) 2021 Microsoft Corporation
+ *
+ * Author: Tushar Sugandhi <tusharsu@linux.microsoft.com>
+ *
+ * File: dm-ima.h
+ *       Header file for device mapper IMA measurements.
+ */
+
+#ifndef DM_IMA_H
+#define DM_IMA_H
+
+#define DM_IMA_MEASUREMENT_BUF_LEN	4096
+#define DM_IMA_DEVICE_BUF_LEN		1024
+#define DM_IMA_TARGET_METADATA_BUF_LEN	128
+#define DM_IMA_TARGET_DATA_BUF_LEN	2048
+
+#ifdef CONFIG_IMA
+
+struct dm_ima_device_table_metadata {
+	/*
+	 * Contains data specific to the device which is common across
+	 * all the targets in the table (e.g. name, uuid, major, minor, etc).
+	 * The values are stored in comma separated list of key1=val1,key2=val2;
+	 * pairs delimited by a semicolon at the end of the list.
+	 */
+	char *device_metadata;
+	unsigned int device_metadata_len;
+	unsigned int num_targets;
+
+	/*
+	 * Contains the sha256 hashes of the IMA measurements of the target
+	 * attributes' key-value pairs from the active/inactive tables.
+	 */
+	char *hash;
+	unsigned int hash_len;
+};
+
+/*
+ * This structure contains device metadata, and table hash for
+ * active and inactive tables for ima measurements.
+ */
+struct dm_ima_measurements {
+	struct dm_ima_device_table_metadata active_table;
+	struct dm_ima_device_table_metadata inactive_table;
+};
+
+void dm_ima_reset_data(struct mapped_device *md);
+void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags);
+
+#else
+
+static inline void dm_ima_reset_data(struct mapped_device *md) {}
+static inline void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags) {}
+
+#endif /* CONFIG_IMA */
+
+#endif /* DM_IMA_H */
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 2575074a2204..d7c3456bf858 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -6,7 +6,7 @@
  */
 
 #include "dm-core.h"
-
+#include "dm-ima.h"
 #include <linux/module.h>
 #include <linux/vmalloc.h>
 #include <linux/miscdevice.h>
@@ -20,6 +20,7 @@
 #include <linux/compat.h>
 
 #include <linux/uaccess.h>
+#include <linux/ima.h>
 
 #define DM_MSG_PREFIX "ioctl"
 #define DM_DRIVER_EMAIL "dm-devel@redhat.com"
@@ -1224,6 +1225,8 @@ static void retrieve_status(struct dm_table *table,
 
 	if (param->flags & DM_STATUS_TABLE_FLAG)
 		type = STATUSTYPE_TABLE;
+	else if (param->flags & DM_IMA_MEASUREMENT_FLAG)
+		type = STATUSTYPE_IMA;
 	else
 		type = STATUSTYPE_INFO;
 
@@ -1425,6 +1428,8 @@ static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_si
 	if (r)
 		goto err_unlock_md_type;
 
+	dm_ima_measure_on_table_load(t, STATUSTYPE_IMA);
+
 	immutable_target_type = dm_get_immutable_target_type(md);
 	if (immutable_target_type &&
 	    (immutable_target_type != dm_table_get_immutable_target_type(t)) &&
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 7981b7287628..33e55ac9ec65 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -8,6 +8,7 @@
 #include "dm-core.h"
 #include "dm-rq.h"
 #include "dm-uevent.h"
+#include "dm-ima.h"
 
 #include <linux/init.h>
 #include <linux/module.h>
@@ -1997,6 +1998,8 @@ int dm_create(int minor, struct mapped_device **result)
 	if (!md)
 		return -ENXIO;
 
+	dm_ima_reset_data(md);
+
 	*result = md;
 	return 0;
 }
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 7457d49acf9a..74486c332946 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -31,7 +31,7 @@ enum dm_queue_mode {
 	DM_TYPE_DAX_BIO_BASED	 = 3,
 };
 
-typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;
+typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE, STATUSTYPE_IMA } status_type_t;
 
 union map_info {
 	void *ptr;
diff --git a/include/uapi/linux/dm-ioctl.h b/include/uapi/linux/dm-ioctl.h
index e5c6e458bdf7..c12ce30b52df 100644
--- a/include/uapi/linux/dm-ioctl.h
+++ b/include/uapi/linux/dm-ioctl.h
@@ -376,4 +376,10 @@ enum {
  */
 #define DM_INTERNAL_SUSPEND_FLAG	(1 << 18) /* Out */
 
+/*
+ * If set, returns in the in buffer passed by UM, the raw table information
+ * that would be measured by IMA subsystem on device state change.
+ */
+#define DM_IMA_MEASUREMENT_FLAG	(1 << 19) /* In */
+
 #endif				/* _LINUX_DM_IOCTL_H */
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 287b90509006..673833f94069 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -985,6 +985,7 @@ void ima_measure_critical_data(const char *event_label,
 				   CRITICAL_DATA, 0, event_label,
 				   hash);
 }
+EXPORT_SYMBOL_GPL(ima_measure_critical_data);
 
 static int __init init_ima(void)
 {
-- 
cgit v1.2.3


From 8eb6fab402e23ae5de216c327fcd0dd6b54e135d Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Mon, 12 Jul 2021 17:48:59 -0700
Subject: dm ima: measure data on device resume

A given block device can load a table multiple times, with different
input parameters, before eventually resuming it.  Further, a device may
be suspended and then resumed.  The device may never resume after a
table-load.  Because of the above valid scenarios for a given device,
it is important to measure and log the device resume event using IMA.

Also, if the table is large, measuring it in clear-text each time the
device changes state, will unnecessarily increase the size of IMA log.
Since the table clear-text is already measured during table-load event,
measuring the hash during resume should be sufficient to validate the
table contents.

Measure the device parameters, and hash of the active table, when the
device is resumed.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-ima.c   | 116 ++++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/md/dm-ima.h   |   3 ++
 drivers/md/dm-ioctl.c |   8 +++-
 3 files changed, 125 insertions(+), 2 deletions(-)

diff --git a/drivers/md/dm-ima.c b/drivers/md/dm-ima.c
index c8f54d9f6c8d..30b9875be63a 100644
--- a/drivers/md/dm-ima.c
+++ b/drivers/md/dm-ima.c
@@ -142,6 +142,26 @@ static void dm_ima_measure_data(const char *event_name, const void *buf, size_t
 		memalloc_noio_restore(noio_flag);
 }
 
+/*
+ * Internal function to allocate and copy current device capacity for IMA measurements.
+ */
+static int dm_ima_alloc_and_copy_capacity_str(struct mapped_device *md, char **capacity_str,
+					      bool noio)
+{
+	sector_t capacity;
+
+	capacity = get_capacity(md->disk);
+
+	*capacity_str = dm_ima_alloc(DM_IMA_DEVICE_CAPACITY_BUF_LEN, GFP_KERNEL, noio);
+	if (!(*capacity_str))
+		return -ENOMEM;
+
+	scnprintf(*capacity_str, DM_IMA_DEVICE_BUF_LEN, "current_device_capacity=%llu;",
+		  capacity);
+
+	return 0;
+}
+
 /*
  * Initialize/reset the dm ima related data structure variables.
  */
@@ -328,3 +348,99 @@ exit:
 	kfree(target_metadata_buf);
 	kfree(target_data_buf);
 }
+
+/*
+ * Measure IMA data on device resume.
+ */
+void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
+{
+	char *device_table_data, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
+	char active[] = "active_table_hash=";
+	unsigned int active_len = strlen(active), capacity_len = 0;
+	unsigned int l = 0;
+	bool noio = true;
+	int r;
+
+	device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
+	if (!device_table_data)
+		return;
+
+	r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+	if (r)
+		goto error;
+
+	if (swap) {
+		if (md->ima.active_table.hash != md->ima.inactive_table.hash)
+			kfree(md->ima.active_table.hash);
+
+		md->ima.active_table.hash = NULL;
+		md->ima.active_table.hash_len = 0;
+
+		if (md->ima.active_table.device_metadata !=
+		    md->ima.inactive_table.device_metadata)
+			kfree(md->ima.active_table.device_metadata);
+
+		md->ima.active_table.device_metadata = NULL;
+		md->ima.active_table.device_metadata_len = 0;
+		md->ima.active_table.num_targets = 0;
+
+		if (md->ima.inactive_table.hash) {
+			md->ima.active_table.hash = md->ima.inactive_table.hash;
+			md->ima.active_table.hash_len = md->ima.inactive_table.hash_len;
+			md->ima.inactive_table.hash = NULL;
+			md->ima.inactive_table.hash_len = 0;
+		}
+
+		if (md->ima.inactive_table.device_metadata) {
+			md->ima.active_table.device_metadata =
+				md->ima.inactive_table.device_metadata;
+			md->ima.active_table.device_metadata_len =
+				md->ima.inactive_table.device_metadata_len;
+			md->ima.active_table.num_targets = md->ima.inactive_table.num_targets;
+			md->ima.inactive_table.device_metadata = NULL;
+			md->ima.inactive_table.device_metadata_len = 0;
+			md->ima.inactive_table.num_targets = 0;
+		}
+	}
+
+	if (md->ima.active_table.device_metadata) {
+		l = md->ima.active_table.device_metadata_len;
+		memcpy(device_table_data, md->ima.active_table.device_metadata, l);
+	}
+
+	if (md->ima.active_table.hash) {
+		memcpy(device_table_data + l, active, active_len);
+		l += active_len;
+
+		memcpy(device_table_data + l, md->ima.active_table.hash,
+		       md->ima.active_table.hash_len);
+		l += md->ima.active_table.hash_len;
+
+		memcpy(device_table_data + l, ";", 1);
+		l++;
+	}
+
+	if (!l) {
+		r = dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio);
+		if (r)
+			goto error;
+
+		scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
+			  "name=%s,uuid=%s;device_resume=no_data;",
+			  dev_name, dev_uuid);
+		l += strlen(device_table_data);
+
+	}
+
+	capacity_len = strlen(capacity_str);
+	memcpy(device_table_data + l, capacity_str, capacity_len);
+	l += capacity_len;
+
+	dm_ima_measure_data("device_resume", device_table_data, l, noio);
+
+	kfree(dev_name);
+	kfree(dev_uuid);
+error:
+	kfree(capacity_str);
+	kfree(device_table_data);
+}
diff --git a/drivers/md/dm-ima.h b/drivers/md/dm-ima.h
index 16afd9a8c0b2..78c36b877ccf 100644
--- a/drivers/md/dm-ima.h
+++ b/drivers/md/dm-ima.h
@@ -15,6 +15,7 @@
 #define DM_IMA_DEVICE_BUF_LEN		1024
 #define DM_IMA_TARGET_METADATA_BUF_LEN	128
 #define DM_IMA_TARGET_DATA_BUF_LEN	2048
+#define DM_IMA_DEVICE_CAPACITY_BUF_LEN	128
 
 #ifdef CONFIG_IMA
 
@@ -48,11 +49,13 @@ struct dm_ima_measurements {
 
 void dm_ima_reset_data(struct mapped_device *md);
 void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags);
+void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap);
 
 #else
 
 static inline void dm_ima_reset_data(struct mapped_device *md) {}
 static inline void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags) {}
+static inline void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap) {}
 
 #endif /* CONFIG_IMA */
 
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index d7c3456bf858..100745cd8f01 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1160,8 +1160,12 @@ static int do_resume(struct dm_ioctl *param)
 
 	if (dm_suspended_md(md)) {
 		r = dm_resume(md);
-		if (!r && !dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr))
-			param->flags |= DM_UEVENT_GENERATED_FLAG;
+		if (!r) {
+			dm_ima_measure_on_device_resume(md, new_map ? true : false);
+
+			if (!dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr))
+				param->flags |= DM_UEVENT_GENERATED_FLAG;
+		}
 	}
 
 	/*
-- 
cgit v1.2.3


From 84010e519f95c863728e4b1d73cf93cda41ac00e Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Mon, 12 Jul 2021 17:49:00 -0700
Subject: dm ima: measure data on device remove

Presence of an active block-device, configured with expected parameters,
is important for an external attestation service to determine if a system
meets the attestation requirements.  Therefore it is important for DM to
measure the device remove events.

Measure device parameters and table hashes when the device is removed,
using either remove or remove_all.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-ima.c   | 119 ++++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/md/dm-ima.h   |   2 +
 drivers/md/dm-ioctl.c |   3 ++
 3 files changed, 124 insertions(+)

diff --git a/drivers/md/dm-ima.c b/drivers/md/dm-ima.c
index 30b9875be63a..4fb230024825 100644
--- a/drivers/md/dm-ima.c
+++ b/drivers/md/dm-ima.c
@@ -444,3 +444,122 @@ error:
 	kfree(capacity_str);
 	kfree(device_table_data);
 }
+
+/*
+ * Measure IMA data on remove.
+ */
+void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
+{
+	char *device_table_data, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
+	char active_table_str[] = "active_table_hash=";
+	char inactive_table_str[] = "inactive_table_hash=";
+	char device_active_str[] = "device_active_metadata=";
+	char device_inactive_str[] = "device_inactive_metadata=";
+	char remove_all_str[] = "remove_all=";
+	unsigned int active_table_len = strlen(active_table_str);
+	unsigned int inactive_table_len = strlen(inactive_table_str);
+	unsigned int device_active_len = strlen(device_active_str);
+	unsigned int device_inactive_len = strlen(device_inactive_str);
+	unsigned int remove_all_len = strlen(remove_all_str);
+	unsigned int capacity_len = 0;
+	unsigned int l = 0;
+	bool noio = true;
+	int r;
+
+	device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN*2, GFP_KERNEL, noio);
+	if (!device_table_data)
+		goto exit;
+
+	r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+	if (r) {
+		kfree(device_table_data);
+		goto exit;
+	}
+
+	if (md->ima.active_table.device_metadata) {
+		memcpy(device_table_data + l, device_active_str, device_active_len);
+		l += device_active_len;
+
+		memcpy(device_table_data + l, md->ima.active_table.device_metadata,
+		       md->ima.active_table.device_metadata_len);
+		l += md->ima.active_table.device_metadata_len;
+	}
+
+	if (md->ima.inactive_table.device_metadata) {
+		memcpy(device_table_data + l, device_inactive_str, device_inactive_len);
+		l += device_inactive_len;
+
+		memcpy(device_table_data + l, md->ima.inactive_table.device_metadata,
+		       md->ima.inactive_table.device_metadata_len);
+		l += md->ima.inactive_table.device_metadata_len;
+	}
+
+	if (md->ima.active_table.hash) {
+		memcpy(device_table_data + l, active_table_str, active_table_len);
+		l += active_table_len;
+
+		memcpy(device_table_data + l, md->ima.active_table.hash,
+			   md->ima.active_table.hash_len);
+		l += md->ima.active_table.hash_len;
+
+		memcpy(device_table_data + l, ",", 1);
+		l++;
+	}
+
+	if (md->ima.inactive_table.hash) {
+		memcpy(device_table_data + l, inactive_table_str, inactive_table_len);
+		l += inactive_table_len;
+
+		memcpy(device_table_data + l, md->ima.inactive_table.hash,
+		       md->ima.inactive_table.hash_len);
+		l += md->ima.inactive_table.hash_len;
+
+		memcpy(device_table_data + l, ",", 1);
+		l++;
+	}
+	/*
+	 * In case both active and inactive tables, and corresponding
+	 * device metadata is cleared/missing - record the name and uuid
+	 * in IMA measurements.
+	 */
+	if (!l) {
+		if (dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio))
+			goto error;
+
+		scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
+			  "name=%s,uuid=%s;device_remove=no_data;",
+			  dev_name, dev_uuid);
+		l += strlen(device_table_data);
+	}
+
+	memcpy(device_table_data + l, remove_all_str, remove_all_len);
+	l += remove_all_len;
+	memcpy(device_table_data + l, remove_all ? "y;" : "n;", 2);
+	l += 2;
+
+	capacity_len = strlen(capacity_str);
+	memcpy(device_table_data + l, capacity_str, capacity_len);
+	l += capacity_len;
+
+	dm_ima_measure_data("device_remove", device_table_data, l, noio);
+
+error:
+	kfree(device_table_data);
+	kfree(capacity_str);
+exit:
+	kfree(md->ima.active_table.device_metadata);
+
+	if (md->ima.active_table.device_metadata !=
+	    md->ima.inactive_table.device_metadata)
+		kfree(md->ima.inactive_table.device_metadata);
+
+	kfree(md->ima.active_table.hash);
+
+	if (md->ima.active_table.hash != md->ima.inactive_table.hash)
+		kfree(md->ima.inactive_table.hash);
+
+	dm_ima_reset_data(md);
+
+	kfree(dev_name);
+	kfree(dev_uuid);
+}
diff --git a/drivers/md/dm-ima.h b/drivers/md/dm-ima.h
index 78c36b877ccf..59bede2454b0 100644
--- a/drivers/md/dm-ima.h
+++ b/drivers/md/dm-ima.h
@@ -50,12 +50,14 @@ struct dm_ima_measurements {
 void dm_ima_reset_data(struct mapped_device *md);
 void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags);
 void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap);
+void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all);
 
 #else
 
 static inline void dm_ima_reset_data(struct mapped_device *md) {}
 static inline void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags) {}
 static inline void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap) {}
+static inline void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all) {}
 
 #endif /* CONFIG_IMA */
 
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 100745cd8f01..59f99759cfec 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -348,6 +348,7 @@ retry:
 			dm_sync_table(md);
 			dm_table_destroy(t);
 		}
+		dm_ima_measure_on_device_remove(md, true);
 		dm_put(md);
 		if (likely(keep_open_devices))
 			dm_destroy(md);
@@ -982,6 +983,8 @@ static int dev_remove(struct file *filp, struct dm_ioctl *param, size_t param_si
 
 	param->flags &= ~DM_DEFERRED_REMOVE;
 
+	dm_ima_measure_on_device_remove(md, false);
+
 	if (!dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr))
 		param->flags |= DM_UEVENT_GENERATED_FLAG;
 
-- 
cgit v1.2.3


From 99169b93838aa4b45dfed7163bd3302f1b375238 Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Mon, 12 Jul 2021 17:49:01 -0700
Subject: dm ima: measure data on table clear

For a given block device, an inactive table slot contains the parameters
to configure the device with.  The inactive table can be cleared
multiple times, accidentally or maliciously, which may impact the
functionality of the device, and compromise the system.  Therefore it is
important to measure and log the event when a table is cleared.

Measure device parameters, and table hashes when the inactive table slot
is cleared.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-ima.c   | 92 +++++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/md/dm-ima.h   |  2 ++
 drivers/md/dm-ioctl.c |  3 ++
 3 files changed, 97 insertions(+)

diff --git a/drivers/md/dm-ima.c b/drivers/md/dm-ima.c
index 4fb230024825..1a22860888fa 100644
--- a/drivers/md/dm-ima.c
+++ b/drivers/md/dm-ima.c
@@ -563,3 +563,95 @@ exit:
 	kfree(dev_name);
 	kfree(dev_uuid);
 }
+
+/*
+ * Measure ima data on table clear.
+ */
+void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map)
+{
+	unsigned int l = 0, capacity_len = 0;
+	char *device_table_data = NULL, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
+	char inactive_str[] = "inactive_table_hash=";
+	unsigned int inactive_len = strlen(inactive_str);
+	bool noio = true;
+	int r;
+
+	device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
+	if (!device_table_data)
+		return;
+
+	r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+	if (r)
+		goto error1;
+
+	if (md->ima.inactive_table.device_metadata_len &&
+	    md->ima.inactive_table.hash_len) {
+		memcpy(device_table_data + l, md->ima.inactive_table.device_metadata,
+		       md->ima.inactive_table.device_metadata_len);
+		l += md->ima.inactive_table.device_metadata_len;
+
+		memcpy(device_table_data + l, inactive_str, inactive_len);
+		l += inactive_len;
+
+		memcpy(device_table_data + l, md->ima.inactive_table.hash,
+			   md->ima.inactive_table.hash_len);
+
+		l += md->ima.inactive_table.hash_len;
+
+		memcpy(device_table_data + l, ";", 1);
+		l++;
+	}
+
+	if (!l) {
+		if (dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio))
+			goto error2;
+
+		scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
+			  "name=%s,uuid=%s;table_clear=no_data;", dev_name, dev_uuid);
+		l += strlen(device_table_data);
+	}
+
+	capacity_len = strlen(capacity_str);
+	memcpy(device_table_data + l, capacity_str, capacity_len);
+	l += capacity_len;
+
+	dm_ima_measure_data("table_clear", device_table_data, l, noio);
+
+	if (new_map) {
+		if (md->ima.inactive_table.hash &&
+		    md->ima.inactive_table.hash != md->ima.active_table.hash)
+			kfree(md->ima.inactive_table.hash);
+
+		md->ima.inactive_table.hash = NULL;
+		md->ima.inactive_table.hash_len = 0;
+
+		if (md->ima.inactive_table.device_metadata &&
+		    md->ima.inactive_table.device_metadata != md->ima.active_table.device_metadata)
+			kfree(md->ima.inactive_table.device_metadata);
+
+		md->ima.inactive_table.device_metadata = NULL;
+		md->ima.inactive_table.device_metadata_len = 0;
+		md->ima.inactive_table.num_targets = 0;
+
+		if (md->ima.active_table.hash) {
+			md->ima.inactive_table.hash = md->ima.active_table.hash;
+			md->ima.inactive_table.hash_len = md->ima.active_table.hash_len;
+		}
+
+		if (md->ima.active_table.device_metadata) {
+			md->ima.inactive_table.device_metadata =
+				md->ima.active_table.device_metadata;
+			md->ima.inactive_table.device_metadata_len =
+				md->ima.active_table.device_metadata_len;
+			md->ima.inactive_table.num_targets =
+				md->ima.active_table.num_targets;
+		}
+	}
+
+	kfree(dev_name);
+	kfree(dev_uuid);
+error2:
+	kfree(capacity_str);
+error1:
+	kfree(device_table_data);
+}
diff --git a/drivers/md/dm-ima.h b/drivers/md/dm-ima.h
index 59bede2454b0..caa5c84017b1 100644
--- a/drivers/md/dm-ima.h
+++ b/drivers/md/dm-ima.h
@@ -51,6 +51,7 @@ void dm_ima_reset_data(struct mapped_device *md);
 void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags);
 void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap);
 void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all);
+void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map);
 
 #else
 
@@ -58,6 +59,7 @@ static inline void dm_ima_reset_data(struct mapped_device *md) {}
 static inline void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags) {}
 static inline void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap) {}
 static inline void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all) {}
+static inline void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map) {}
 
 #endif /* CONFIG_IMA */
 
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 59f99759cfec..7c902e67cd10 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1505,6 +1505,7 @@ static int table_clear(struct file *filp, struct dm_ioctl *param, size_t param_s
 	struct hash_cell *hc;
 	struct mapped_device *md;
 	struct dm_table *old_map = NULL;
+	bool has_new_map = false;
 
 	down_write(&_hash_lock);
 
@@ -1518,6 +1519,7 @@ static int table_clear(struct file *filp, struct dm_ioctl *param, size_t param_s
 	if (hc->new_map) {
 		old_map = hc->new_map;
 		hc->new_map = NULL;
+		has_new_map = true;
 	}
 
 	param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
@@ -1529,6 +1531,7 @@ static int table_clear(struct file *filp, struct dm_ioctl *param, size_t param_s
 		dm_sync_table(md);
 		dm_table_destroy(old_map);
 	}
+	dm_ima_measure_on_table_clear(md, has_new_map);
 	dm_put(md);
 
 	return 0;
-- 
cgit v1.2.3


From 7d1d1df8ce31491edda5effb216450aad8f05c0d Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Mon, 12 Jul 2021 17:49:02 -0700
Subject: dm ima: measure data on device rename

A given block device is identified by it's name and UUID.  However, both
these parameters can be renamed.  For an external attestation service to
correctly attest a given device, it needs to keep track of these rename
events.

Update the device data with the new values for IMA measurements.  Measure
both old and new device name/UUID parameters in the same IMA measurement
event, so that the old and the new values can be connected later.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-ima.c   | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/md/dm-ima.h   |  2 ++
 drivers/md/dm-ioctl.c |  3 +++
 3 files changed, 53 insertions(+)

diff --git a/drivers/md/dm-ima.c b/drivers/md/dm-ima.c
index 1a22860888fa..91ea4a7202ab 100644
--- a/drivers/md/dm-ima.c
+++ b/drivers/md/dm-ima.c
@@ -655,3 +655,51 @@ error2:
 error1:
 	kfree(device_table_data);
 }
+
+/*
+ * Measure IMA data on device rename.
+ */
+void dm_ima_measure_on_device_rename(struct mapped_device *md)
+{
+	char *old_device_data = NULL, *new_device_data = NULL, *combined_device_data = NULL;
+	char *new_dev_name = NULL, *new_dev_uuid = NULL, *capacity_str = NULL;
+	bool noio = true;
+	int r;
+
+	if (dm_ima_alloc_and_copy_device_data(md, &new_device_data,
+					      md->ima.active_table.num_targets, noio))
+		return;
+
+	if (dm_ima_alloc_and_copy_name_uuid(md, &new_dev_name, &new_dev_uuid, noio))
+		goto error;
+
+	combined_device_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN * 2, GFP_KERNEL, noio);
+	if (!combined_device_data)
+		goto error;
+
+	r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+	if (r)
+		goto error;
+
+	old_device_data = md->ima.active_table.device_metadata;
+
+	md->ima.active_table.device_metadata = new_device_data;
+	md->ima.active_table.device_metadata_len = strlen(new_device_data);
+
+	scnprintf(combined_device_data, DM_IMA_DEVICE_BUF_LEN * 2, "%snew_name=%s,new_uuid=%s;%s",
+		  old_device_data, new_dev_name, new_dev_uuid, capacity_str);
+
+	dm_ima_measure_data("device_rename", combined_device_data, strlen(combined_device_data),
+			    noio);
+
+	goto exit;
+
+error:
+	kfree(new_device_data);
+exit:
+	kfree(capacity_str);
+	kfree(combined_device_data);
+	kfree(old_device_data);
+	kfree(new_dev_name);
+	kfree(new_dev_uuid);
+}
diff --git a/drivers/md/dm-ima.h b/drivers/md/dm-ima.h
index caa5c84017b1..6e6f18bf05b4 100644
--- a/drivers/md/dm-ima.h
+++ b/drivers/md/dm-ima.h
@@ -52,6 +52,7 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap);
 void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all);
 void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map);
+void dm_ima_measure_on_device_rename(struct mapped_device *md);
 
 #else
 
@@ -60,6 +61,7 @@ static inline void dm_ima_measure_on_table_load(struct dm_table *table, unsigned
 static inline void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap) {}
 static inline void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all) {}
 static inline void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map) {}
+static inline void dm_ima_measure_on_device_rename(struct mapped_device *md) {}
 
 #endif /* CONFIG_IMA */
 
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 7c902e67cd10..21fe8652b095 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -485,6 +485,9 @@ static struct mapped_device *dm_hash_rename(struct dm_ioctl *param,
 		param->flags |= DM_UEVENT_GENERATED_FLAG;
 
 	md = hc->md;
+
+	dm_ima_measure_on_device_rename(md);
+
 	up_write(&_hash_lock);
 	kfree(old_name);
 
-- 
cgit v1.2.3


From 8ec456629d0bf051e41ef2c87a60755f941dd11c Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Mon, 12 Jul 2021 17:49:03 -0700
Subject: dm: update target status functions to support IMA measurement

For device mapper targets to take advantage of IMA's measurement
capabilities, the status functions for the individual targets need to be
updated to handle the status_type_t case for value STATUSTYPE_IMA.

Update status functions for the following target types, to log their
respective attributes to be measured using IMA.
 01. cache
 02. crypt
 03. integrity
 04. linear
 05. mirror
 06. multipath
 07. raid
 08. snapshot
 09. striped
 10. verity

For rest of the targets, handle the STATUSTYPE_IMA case by setting the
measurement buffer to NULL.

For IMA to measure the data on a given system, the IMA policy on the
system needs to be updated to have the following line, and the system
needs to be restarted for the measurements to take effect.

/etc/ima/ima-policy
 measure func=CRITICAL_DATA label=device-mapper template=ima-buf

The measurements will be reflected in the IMA logs, which are located at:

/sys/kernel/security/integrity/ima/ascii_runtime_measurements
/sys/kernel/security/integrity/ima/binary_runtime_measurements

These IMA logs can later be consumed by various attestation clients
running on the system, and send them to external services for attesting
the system.

The DM target data measured by IMA subsystem can alternatively
be queried from userspace by setting DM_IMA_MEASUREMENT_FLAG with
DM_TABLE_STATUS_CMD.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-cache-target.c               | 24 +++++++++++++++++
 drivers/md/dm-clone-target.c               |  5 ++++
 drivers/md/dm-crypt.c                      | 27 ++++++++++++++++++++
 drivers/md/dm-delay.c                      |  4 +++
 drivers/md/dm-dust.c                       |  4 +++
 drivers/md/dm-ebs-target.c                 |  3 +++
 drivers/md/dm-era-target.c                 |  4 +++
 drivers/md/dm-flakey.c                     |  4 +++
 drivers/md/dm-integrity.c                  | 25 ++++++++++++++++++
 drivers/md/dm-linear.c                     | 10 ++++++--
 drivers/md/dm-log-userspace-base.c         |  3 +++
 drivers/md/dm-log-writes.c                 |  4 +++
 drivers/md/dm-log.c                        | 10 ++++++++
 drivers/md/dm-mpath.c                      | 28 ++++++++++++++++++++
 drivers/md/dm-ps-historical-service-time.c |  3 +++
 drivers/md/dm-ps-io-affinity.c             |  3 +++
 drivers/md/dm-ps-queue-length.c            |  3 +++
 drivers/md/dm-ps-round-robin.c             |  4 +++
 drivers/md/dm-ps-service-time.c            |  3 +++
 drivers/md/dm-raid.c                       | 39 ++++++++++++++++++++++++++++
 drivers/md/dm-raid1.c                      | 17 +++++++++++++
 drivers/md/dm-snap-persistent.c            |  4 +++
 drivers/md/dm-snap-transient.c             |  4 +++
 drivers/md/dm-snap.c                       | 13 ++++++++++
 drivers/md/dm-stripe.c                     | 15 +++++++++++
 drivers/md/dm-switch.c                     |  4 +++
 drivers/md/dm-thin.c                       |  8 ++++++
 drivers/md/dm-unstripe.c                   |  4 +++
 drivers/md/dm-verity-target.c              | 41 ++++++++++++++++++++++++++++++
 drivers/md/dm-writecache.c                 |  3 +++
 drivers/md/dm-zoned-target.c               |  3 +++
 include/linux/device-mapper.h              |  4 +++
 32 files changed, 328 insertions(+), 2 deletions(-)

diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index 8e4ced5a2516..bdd500447dea 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -3122,6 +3122,30 @@ static void cache_status(struct dm_target *ti, status_type_t type,
 			DMEMIT(" %s", cache->ctr_args[i]);
 		if (cache->nr_ctr_args)
 			DMEMIT(" %s", cache->ctr_args[cache->nr_ctr_args - 1]);
+		break;
+
+	case STATUSTYPE_IMA:
+		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		if (get_cache_mode(cache) == CM_FAIL)
+			DMEMIT(",metadata_mode=fail");
+		else if (get_cache_mode(cache) == CM_READ_ONLY)
+			DMEMIT(",metadata_mode=ro");
+		else
+			DMEMIT(",metadata_mode=rw");
+
+		format_dev_t(buf, cache->metadata_dev->bdev->bd_dev);
+		DMEMIT(",cache_metadata_device=%s", buf);
+		format_dev_t(buf, cache->cache_dev->bdev->bd_dev);
+		DMEMIT(",cache_device=%s", buf);
+		format_dev_t(buf, cache->origin_dev->bdev->bd_dev);
+		DMEMIT(",cache_origin_device=%s", buf);
+		DMEMIT(",writethrough=%c", writethrough_mode(cache) ? 'y' : 'n');
+		DMEMIT(",writeback=%c", writeback_mode(cache) ? 'y' : 'n');
+		DMEMIT(",passthrough=%c", passthrough_mode(cache) ? 'y' : 'n');
+		DMEMIT(",metadata2=%c", cache->features.metadata_version == 2 ? 'y' : 'n');
+		DMEMIT(",no_discard_passdown=%c", cache->features.discard_passdown ? 'n' : 'y');
+		DMEMIT(";");
+		break;
 	}
 
 	return;
diff --git a/drivers/md/dm-clone-target.c b/drivers/md/dm-clone-target.c
index a90bdf9b2ca6..84dbe08ad205 100644
--- a/drivers/md/dm-clone-target.c
+++ b/drivers/md/dm-clone-target.c
@@ -1499,6 +1499,11 @@ static void clone_status(struct dm_target *ti, status_type_t type,
 
 		for (i = 0; i < clone->nr_ctr_args; i++)
 			DMEMIT(" %s", clone->ctr_args[i]);
+		break;
+
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 
 	return;
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 50f4cbd600d5..80fdc42ce3c8 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -3485,7 +3485,34 @@ static void crypt_status(struct dm_target *ti, status_type_t type,
 			if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
 				DMEMIT(" iv_large_sectors");
 		}
+		break;
+
+	case STATUSTYPE_IMA:
+		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n');
+		DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n');
+		DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ?
+		       'y' : 'n');
+		DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ?
+		       'y' : 'n');
+		DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ?
+		       'y' : 'n');
+		DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ?
+		       'y' : 'n');
 
+		if (cc->on_disk_tag_size)
+			DMEMIT(",integrity_tag_size=%u,cipher_auth=%s",
+			       cc->on_disk_tag_size, cc->cipher_auth);
+		if (cc->sector_size != (1 << SECTOR_SHIFT))
+			DMEMIT(",sector_size=%d", cc->sector_size);
+		if (cc->cipher_string)
+			DMEMIT(",cipher_string=%s", cc->cipher_string);
+
+		DMEMIT(",key_size=%u", cc->key_size);
+		DMEMIT(",key_parts=%u", cc->key_parts);
+		DMEMIT(",key_extra_size=%u", cc->key_extra_size);
+		DMEMIT(",key_mac_size=%u", cc->key_mac_size);
+		DMEMIT(";");
 		break;
 	}
 }
diff --git a/drivers/md/dm-delay.c b/drivers/md/dm-delay.c
index 2628a832787b..59e51d285b0e 100644
--- a/drivers/md/dm-delay.c
+++ b/drivers/md/dm-delay.c
@@ -326,6 +326,10 @@ static void delay_status(struct dm_target *ti, status_type_t type,
 			DMEMIT_DELAY_CLASS(&dc->flush);
 		}
 		break;
+
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-dust.c b/drivers/md/dm-dust.c
index cbe1058ee589..3163e2b1418e 100644
--- a/drivers/md/dm-dust.c
+++ b/drivers/md/dm-dust.c
@@ -527,6 +527,10 @@ static void dust_status(struct dm_target *ti, status_type_t type,
 		DMEMIT("%s %llu %u", dd->dev->name,
 		       (unsigned long long)dd->start, dd->blksz);
 		break;
+
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-ebs-target.c b/drivers/md/dm-ebs-target.c
index 71475a2410be..ec8426611cc6 100644
--- a/drivers/md/dm-ebs-target.c
+++ b/drivers/md/dm-ebs-target.c
@@ -401,6 +401,9 @@ static void ebs_status(struct dm_target *ti, status_type_t type,
 		snprintf(result, maxlen, ec->u_bs_set ? "%s %llu %u %u" : "%s %llu %u",
 			 ec->dev->name, (unsigned long long) ec->start, ec->e_bs, ec->u_bs);
 		break;
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-era-target.c b/drivers/md/dm-era-target.c
index 3b748393fca5..2a78f6874143 100644
--- a/drivers/md/dm-era-target.c
+++ b/drivers/md/dm-era-target.c
@@ -1644,6 +1644,10 @@ static void era_status(struct dm_target *ti, status_type_t type,
 		format_dev_t(buf, era->origin_dev->bdev->bd_dev);
 		DMEMIT("%s %u", buf, era->sectors_per_block);
 		break;
+
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 
 	return;
diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
index 5877220c01ed..4b94ffe6f2d4 100644
--- a/drivers/md/dm-flakey.c
+++ b/drivers/md/dm-flakey.c
@@ -440,6 +440,10 @@ static void flakey_status(struct dm_target *ti, status_type_t type,
 			       fc->corrupt_bio_value, fc->corrupt_bio_flags);
 
 		break;
+
+	case STATUSTYPE_IMA:
+		result[0] = '\0';
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index 20f2510db1f6..40f8116c8e44 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -3306,6 +3306,31 @@ static void dm_integrity_status(struct dm_target *ti, status_type_t type,
 		EMIT_ALG(journal_mac_alg, "journal_mac");
 		break;
 	}
+	case STATUSTYPE_IMA:
+		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		DMEMIT(",dev_name=%s,start=%llu,tag_size=%u,mode=%c",
+			ic->dev->name, ic->start, ic->tag_size, ic->mode);
+
+		if (ic->meta_dev)
+			DMEMIT(",meta_device=%s", ic->meta_dev->name);
+		if (ic->sectors_per_block != 1)
+			DMEMIT(",block_size=%u", ic->sectors_per_block << SECTOR_SHIFT);
+
+		DMEMIT(",recalculate=%c", (ic->sb->flags & cpu_to_le32(SB_FLAG_RECALCULATING)) ?
+		       'y' : 'n');
+		DMEMIT(",allow_discards=%c", ic->discard ? 'y' : 'n');
+		DMEMIT(",fix_padding=%c",
+		       ((ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_PADDING)) != 0) ? 'y' : 'n');
+		DMEMIT(",fix_hmac=%c",
+		       ((ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_HMAC)) != 0) ? 'y' : 'n');
+		DMEMIT(",legacy_recalculate=%c", ic->legacy_recalculate ? 'y' : 'n');
+
+		DMEMIT(",journal_sectors=%u", ic->initial_sectors - SB_SECTORS);
+		DMEMIT(",interleave_sectors=%u", 1U << ic->sb->log2_interleave_sectors);
+		DMEMIT(",buffer_sectors=%u", 1U << ic->log2_buffer_sectors);
+		DMEMIT(",mode=%c", ic->mode);
+		DMEMIT(";");
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index c91f1e2e2f65..679b4c0a2eea 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -106,6 +106,7 @@ static void linear_status(struct dm_target *ti, status_type_t type,
 			  unsigned status_flags, char *result, unsigned maxlen)
 {
 	struct linear_c *lc = (struct linear_c *) ti->private;
+	size_t sz = 0;
 
 	switch (type) {
 	case STATUSTYPE_INFO:
@@ -113,8 +114,13 @@ static void linear_status(struct dm_target *ti, status_type_t type,
 		break;
 
 	case STATUSTYPE_TABLE:
-		snprintf(result, maxlen, "%s %llu", lc->dev->name,
-				(unsigned long long)lc->start);
+		DMEMIT("%s %llu", lc->dev->name, (unsigned long long)lc->start);
+		break;
+
+	case STATUSTYPE_IMA:
+		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		DMEMIT(",device_name=%s,start=%llu;", lc->dev->name,
+		       (unsigned long long)lc->start);
 		break;
 	}
 }
diff --git a/drivers/md/dm-log-userspace-base.c b/drivers/md/dm-log-userspace-base.c
index 52090bee17c2..9ab93ebea889 100644
--- a/drivers/md/dm-log-userspace-base.c
+++ b/drivers/md/dm-log-userspace-base.c
@@ -820,6 +820,9 @@ static int userspace_status(struct dm_dirty_log *log, status_type_t status_type,
 			DMEMIT("integrated_flush ");
 		DMEMIT("%s ", table_args);
 		break;
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 	return (r) ? 0 : (int)sz;
 }
diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index 57882654ffee..d93a4db23512 100644
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -834,6 +834,10 @@ static void log_writes_status(struct dm_target *ti, status_type_t type,
 	case STATUSTYPE_TABLE:
 		DMEMIT("%s %s", lc->dev->name, lc->logdev->name);
 		break;
+
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c
index 33e71ea6cc14..1ecf75ef276a 100644
--- a/drivers/md/dm-log.c
+++ b/drivers/md/dm-log.c
@@ -793,6 +793,11 @@ static int core_status(struct dm_dirty_log *log, status_type_t status,
 		DMEMIT("%s %u %u ", log->type->name,
 		       lc->sync == DEFAULTSYNC ? 1 : 2, lc->region_size);
 		DMEMIT_SYNC;
+		break;
+
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 
 	return sz;
@@ -817,6 +822,11 @@ static int disk_status(struct dm_dirty_log *log, status_type_t status,
 		       lc->sync == DEFAULTSYNC ? 2 : 3, lc->log_dev->name,
 		       lc->region_size);
 		DMEMIT_SYNC;
+		break;
+
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 
 	return sz;
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index bced42f082b0..c3c514a9edbb 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1904,6 +1904,34 @@ static void multipath_status(struct dm_target *ti, status_type_t type,
 			}
 		}
 		break;
+
+	case STATUSTYPE_IMA:
+		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		list_for_each_entry(pg, &m->priority_groups, list) {
+			if (pg->bypassed)
+				state = 'D';	/* Disabled */
+			else if (pg == m->current_pg)
+				state = 'A';	/* Currently Active */
+			else
+				state = 'E';	/* Enabled */
+			DMEMIT(",pg_state=%c", state);
+			DMEMIT(",nr_pgpaths=%u", pg->nr_pgpaths);
+			DMEMIT(",path_selector_name=%s", pg->ps.type->name);
+
+			list_for_each_entry(p, &pg->pgpaths, list) {
+				DMEMIT(",path_name=%s,is_active=%c,fail_count=%u",
+				       p->path.dev->name, p->is_active ? 'A' : 'F',
+				       p->fail_count);
+				if (pg->ps.type->status) {
+					DMEMIT(",path_selector_status=");
+					sz += pg->ps.type->status(&pg->ps, &p->path,
+								  type, result + sz,
+								  maxlen - sz);
+				}
+			}
+		}
+		DMEMIT(";");
+		break;
 	}
 
 	spin_unlock_irqrestore(&m->lock, flags);
diff --git a/drivers/md/dm-ps-historical-service-time.c b/drivers/md/dm-ps-historical-service-time.c
index 186f91e2752c..1856a1b125cc 100644
--- a/drivers/md/dm-ps-historical-service-time.c
+++ b/drivers/md/dm-ps-historical-service-time.c
@@ -255,6 +255,9 @@ static int hst_status(struct path_selector *ps, struct dm_path *path,
 		case STATUSTYPE_TABLE:
 			DMEMIT("0 ");
 			break;
+		case STATUSTYPE_IMA:
+			*result = '\0';
+			break;
 		}
 	}
 
diff --git a/drivers/md/dm-ps-io-affinity.c b/drivers/md/dm-ps-io-affinity.c
index cb8e83bfb1a7..f74501e65a8e 100644
--- a/drivers/md/dm-ps-io-affinity.c
+++ b/drivers/md/dm-ps-io-affinity.c
@@ -170,6 +170,9 @@ static int ioa_status(struct path_selector *ps, struct dm_path *path,
 		pi = path->pscontext;
 		DMEMIT("%*pb ", cpumask_pr_args(pi->cpumask));
 		break;
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 
 	return sz;
diff --git a/drivers/md/dm-ps-queue-length.c b/drivers/md/dm-ps-queue-length.c
index 5fd018d18418..cef70657bbbc 100644
--- a/drivers/md/dm-ps-queue-length.c
+++ b/drivers/md/dm-ps-queue-length.c
@@ -102,6 +102,9 @@ static int ql_status(struct path_selector *ps, struct dm_path *path,
 		case STATUSTYPE_TABLE:
 			DMEMIT("%u ", pi->repeat_count);
 			break;
+		case STATUSTYPE_IMA:
+			*result = '\0';
+			break;
 		}
 	}
 
diff --git a/drivers/md/dm-ps-round-robin.c b/drivers/md/dm-ps-round-robin.c
index bdbb7e6e8212..27f44c5fa04e 100644
--- a/drivers/md/dm-ps-round-robin.c
+++ b/drivers/md/dm-ps-round-robin.c
@@ -100,6 +100,10 @@ static int rr_status(struct path_selector *ps, struct dm_path *path,
 			pi = path->pscontext;
 			DMEMIT("%u ", pi->repeat_count);
 			break;
+
+		case STATUSTYPE_IMA:
+			*result = '\0';
+			break;
 		}
 	}
 
diff --git a/drivers/md/dm-ps-service-time.c b/drivers/md/dm-ps-service-time.c
index 9cfda665e9eb..3ec9c33265c5 100644
--- a/drivers/md/dm-ps-service-time.c
+++ b/drivers/md/dm-ps-service-time.c
@@ -99,6 +99,9 @@ static int st_status(struct path_selector *ps, struct dm_path *path,
 			DMEMIT("%u %u ", pi->repeat_count,
 			       pi->relative_throughput);
 			break;
+		case STATUSTYPE_IMA:
+			result[0] = '\0';
+			break;
 		}
 	}
 
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index bf4a467fc73a..d9ef52159a22 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -3671,6 +3671,45 @@ static void raid_status(struct dm_target *ti, status_type_t type,
 		for (i = 0; i < rs->raid_disks; i++)
 			DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),
 					 __get_dev_name(rs->dev[i].data_dev));
+		break;
+
+	case STATUSTYPE_IMA:
+		rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
+		if (!rt)
+			return;
+
+		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		DMEMIT(",raid_type=%s,raid_disks=%d", rt->name, mddev->raid_disks);
+
+		/* Access most recent mddev properties for status output */
+		smp_rmb();
+		recovery = rs->md.recovery;
+		state = decipher_sync_action(mddev, recovery);
+		DMEMIT(",raid_state=%s", sync_str(state));
+
+		for (i = 0; i < rs->raid_disks; i++) {
+			DMEMIT(",raid_device_%d_status=", i);
+			DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
+		}
+
+		if (rt_is_raid456(rt)) {
+			DMEMIT(",journal_dev_mode=");
+			switch (rs->journal_dev.mode) {
+			case R5C_JOURNAL_MODE_WRITE_THROUGH:
+				DMEMIT("%s",
+				       _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_THROUGH].param);
+				break;
+			case R5C_JOURNAL_MODE_WRITE_BACK:
+				DMEMIT("%s",
+				       _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_BACK].param);
+				break;
+			default:
+				DMEMIT("invalid");
+				break;
+			}
+		}
+		DMEMIT(";");
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c
index ebb4810cc3b4..8811d484fdd1 100644
--- a/drivers/md/dm-raid1.c
+++ b/drivers/md/dm-raid1.c
@@ -1435,6 +1435,23 @@ static void mirror_status(struct dm_target *ti, status_type_t type,
 		}
 
 		break;
+
+	case STATUSTYPE_IMA:
+		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		DMEMIT(",nr_mirrors=%d", ms->nr_mirrors);
+		for (m = 0; m < ms->nr_mirrors; m++) {
+			DMEMIT(",mirror_device_%d=%s", m, ms->mirror[m].dev->name);
+			DMEMIT(",mirror_device_%d_status=%c",
+			       m, device_status_char(&(ms->mirror[m])));
+		}
+
+		DMEMIT(",handle_errors=%c", errors_handled(ms) ? 'y' : 'n');
+		DMEMIT(",keep_log=%c", keep_log(ms) ? 'y' : 'n');
+
+		DMEMIT(",log_type_status=");
+		sz += log->type->status(log, type, result+sz, maxlen-sz);
+		DMEMIT(";");
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c
index 9ab4bf651ca9..3bb5cff5d6fc 100644
--- a/drivers/md/dm-snap-persistent.c
+++ b/drivers/md/dm-snap-persistent.c
@@ -908,6 +908,10 @@ static unsigned persistent_status(struct dm_exception_store *store,
 	case STATUSTYPE_TABLE:
 		DMEMIT(" %s %llu", store->userspace_supports_overflow ? "PO" : "P",
 		       (unsigned long long)store->chunk_size);
+		break;
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 
 	return sz;
diff --git a/drivers/md/dm-snap-transient.c b/drivers/md/dm-snap-transient.c
index 4d50a12cf00c..0e0ae4c36b37 100644
--- a/drivers/md/dm-snap-transient.c
+++ b/drivers/md/dm-snap-transient.c
@@ -95,6 +95,10 @@ static unsigned transient_status(struct dm_exception_store *store,
 		break;
 	case STATUSTYPE_TABLE:
 		DMEMIT(" N %llu", (unsigned long long)store->chunk_size);
+		break;
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 
 	return sz;
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 751ec5ea1dbb..dcf34c6b05ad 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -2390,6 +2390,16 @@ static void snapshot_status(struct dm_target *ti, status_type_t type,
 				DMEMIT(" discard_passdown_origin");
 		}
 		break;
+
+	case STATUSTYPE_IMA:
+		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		DMEMIT(",snap_origin_name=%s", snap->origin->name);
+		DMEMIT(",snap_cow_name=%s", snap->cow->name);
+		DMEMIT(",snap_valid=%c", snap->valid ? 'y' : 'n');
+		DMEMIT(",snap_merge_failed=%c", snap->merge_failed ? 'y' : 'n');
+		DMEMIT(",snapshot_overflowed=%c", snap->snapshot_overflowed ? 'y' : 'n');
+		DMEMIT(";");
+		break;
 	}
 }
 
@@ -2734,6 +2744,9 @@ static void origin_status(struct dm_target *ti, status_type_t type,
 	case STATUSTYPE_TABLE:
 		snprintf(result, maxlen, "%s", o->dev->name);
 		break;
+	case STATUSTYPE_IMA:
+		result[0] = '\0';
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index df359d33cda8..6660b6b53d5b 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -428,6 +428,21 @@ static void stripe_status(struct dm_target *ti, status_type_t type,
 			DMEMIT(" %s %llu", sc->stripe[i].dev->name,
 			    (unsigned long long)sc->stripe[i].physical_start);
 		break;
+
+	case STATUSTYPE_IMA:
+		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		DMEMIT(",stripes=%d,chunk_size=%llu", sc->stripes,
+		       (unsigned long long)sc->chunk_size);
+
+		for (i = 0; i < sc->stripes; i++) {
+			DMEMIT(",stripe_%d_device_name=%s", i, sc->stripe[i].dev->name);
+			DMEMIT(",stripe_%d_physical_start=%llu", i,
+			       (unsigned long long)sc->stripe[i].physical_start);
+			DMEMIT(",stripe_%d_status=%c", i,
+			       atomic_read(&(sc->stripe[i].error_count)) ? 'D' : 'A');
+		}
+		DMEMIT(";");
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-switch.c b/drivers/md/dm-switch.c
index 262e2b0fd975..028a92ff6d57 100644
--- a/drivers/md/dm-switch.c
+++ b/drivers/md/dm-switch.c
@@ -504,6 +504,10 @@ static void switch_status(struct dm_target *ti, status_type_t type,
 			DMEMIT(" %s %llu", sctx->path_list[path_nr].dmdev->name,
 			       (unsigned long long)sctx->path_list[path_nr].start);
 		break;
+
+	case STATUSTYPE_IMA:
+		result[0] = '\0';
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 985baee3a678..4c67b77c23c1 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -4012,6 +4012,10 @@ static void pool_status(struct dm_target *ti, status_type_t type,
 		       (unsigned long long)pt->low_water_blocks);
 		emit_flags(&pt->requested_pf, result, sz, maxlen);
 		break;
+
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 	return;
 
@@ -4423,6 +4427,10 @@ static void thin_status(struct dm_target *ti, status_type_t type,
 			if (tc->origin_dev)
 				DMEMIT(" %s", format_dev_t(buf, tc->origin_dev->bdev->bd_dev));
 			break;
+
+		case STATUSTYPE_IMA:
+			*result = '\0';
+			break;
 		}
 	}
 
diff --git a/drivers/md/dm-unstripe.c b/drivers/md/dm-unstripe.c
index 7357c1bd5863..fdc8921e5c19 100644
--- a/drivers/md/dm-unstripe.c
+++ b/drivers/md/dm-unstripe.c
@@ -156,6 +156,10 @@ static void unstripe_status(struct dm_target *ti, status_type_t type,
 		       uc->stripes, (unsigned long long)uc->chunk_size, uc->unstripe,
 		       uc->dev->name, (unsigned long long)uc->physical_start);
 		break;
+
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index d3e76aefc1a6..bfefa100c265 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -772,6 +772,47 @@ static void verity_status(struct dm_target *ti, status_type_t type,
 			DMEMIT(" " DM_VERITY_ROOT_HASH_VERIFICATION_OPT_SIG_KEY
 				" %s", v->signature_key_desc);
 		break;
+
+	case STATUSTYPE_IMA:
+		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		DMEMIT(",hash_failed=%c", v->hash_failed ? 'C' : 'V');
+		DMEMIT(",verity_version=%u", v->version);
+		DMEMIT(",data_device_name=%s", v->data_dev->name);
+		DMEMIT(",hash_device_name=%s", v->hash_dev->name);
+		DMEMIT(",verity_algorithm=%s", v->alg_name);
+
+		DMEMIT(",root_digest=");
+		for (x = 0; x < v->digest_size; x++)
+			DMEMIT("%02x", v->root_digest[x]);
+
+		DMEMIT(",salt=");
+		if (!v->salt_size)
+			DMEMIT("-");
+		else
+			for (x = 0; x < v->salt_size; x++)
+				DMEMIT("%02x", v->salt[x]);
+
+		DMEMIT(",ignore_zero_blocks=%c", v->zero_digest ? 'y' : 'n');
+		DMEMIT(",check_at_most_once=%c", v->validated_blocks ? 'y' : 'n');
+
+		if (v->mode != DM_VERITY_MODE_EIO) {
+			DMEMIT(",verity_mode=");
+			switch (v->mode) {
+			case DM_VERITY_MODE_LOGGING:
+				DMEMIT(DM_VERITY_OPT_LOGGING);
+				break;
+			case DM_VERITY_MODE_RESTART:
+				DMEMIT(DM_VERITY_OPT_RESTART);
+				break;
+			case DM_VERITY_MODE_PANIC:
+				DMEMIT(DM_VERITY_OPT_PANIC);
+				break;
+			default:
+				DMEMIT("invalid");
+			}
+		}
+		DMEMIT(";");
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index e1d7234eec3f..18320444fb0a 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -2723,6 +2723,9 @@ static void writecache_status(struct dm_target *ti, status_type_t type,
 		if (wc->pause_set)
 			DMEMIT(" pause_writeback %u", wc->pause_value);
 		break;
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 }
 
diff --git a/drivers/md/dm-zoned-target.c b/drivers/md/dm-zoned-target.c
index 7e88df64d197..ae1bc48c0043 100644
--- a/drivers/md/dm-zoned-target.c
+++ b/drivers/md/dm-zoned-target.c
@@ -1119,6 +1119,9 @@ static void dmz_status(struct dm_target *ti, status_type_t type,
 			DMEMIT(" %s", buf);
 		}
 		break;
+	case STATUSTYPE_IMA:
+		*result = '\0';
+		break;
 	}
 	return;
 }
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 74486c332946..a92260273eb2 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -603,6 +603,10 @@ void dm_destroy_keyslot_manager(struct blk_keyslot_manager *ksm);
 #define DMEMIT(x...) sz += ((sz >= maxlen) ? \
 			  0 : scnprintf(result + sz, maxlen - sz, x))
 
+#define DMEMIT_TARGET_NAME_VERSION(y) \
+		DMEMIT("target_name=%s,target_version=%u.%u.%u", \
+		       (y)->name, (y)->version[0], (y)->version[1], (y)->version[2])
+
 /*
  * Definitions of return values from target end_io function.
  */
-- 
cgit v1.2.3


From 00d43995f0dd7a25961b87f953474d34043d4d4e Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Mon, 12 Jul 2021 17:49:04 -0700
Subject: dm: add documentation for IMA measurement support

To interpret various DM target measurement data in IMA logs,
a separate documentation page is needed under
Documentation/admin-guide/device-mapper.

Add documentation to help system administrators and attestation
client/server component owners to interpret the measurement
data generated by various DM targets, on various device/table state
changes.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 Documentation/admin-guide/device-mapper/dm-ima.rst | 306 +++++++++++++++++++++
 Documentation/admin-guide/device-mapper/index.rst  |   1 +
 2 files changed, 307 insertions(+)
 create mode 100644 Documentation/admin-guide/device-mapper/dm-ima.rst

diff --git a/Documentation/admin-guide/device-mapper/dm-ima.rst b/Documentation/admin-guide/device-mapper/dm-ima.rst
new file mode 100644
index 000000000000..41894112ff26
--- /dev/null
+++ b/Documentation/admin-guide/device-mapper/dm-ima.rst
@@ -0,0 +1,306 @@
+======
+dm-ima
+======
+
+For a given system, various external services/infrastructure tools
+(including the attestation service) interact with it - both during the
+setup and during rest of the system run-time.  They share sensitive data
+and/or execute critical workload on that system.  The external services
+may want to verify the current run-time state of the relevant kernel
+subsystems before fully trusting the system with business-critical
+data/workload.
+
+Device mapper plays a critical role on a given system by providing
+various important functionalities to the block devices using various
+target types like crypt, verity, integrity etc.  Each of these target
+types’ functionalities can be configured with various attributes.
+The attributes chosen to configure these target types can significantly
+impact the security profile of the block device, and in-turn, of the
+system itself.  For instance, the type of encryption algorithm and the
+key size determines the strength of encryption for a given block device.
+
+Therefore, verifying the current state of various block devices as well
+as their various target attributes is crucial for external services before
+fully trusting the system with business-critical data/workload.
+
+IMA kernel subsystem provides the necessary functionality for
+device mapper to measure the state and configuration of
+various block devices -
+  - BY device mapper itself, from within the kernel,
+  - in a tamper resistant way,
+  - and re-measured - triggered on state/configuration change.
+
+Setting the IMA Policy:
+=======================
+For IMA to measure the data on a given system, the IMA policy on the
+system needs to be updated to have following line, and the system needs
+to be restarted for the measurements to take effect.
+
+/etc/ima/ima-policy
+ measure func=CRITICAL_DATA label=device-mapper template=ima-buf
+
+The measurements will be reflected in the IMA logs, which are located at:
+
+/sys/kernel/security/integrity/ima/ascii_runtime_measurements
+/sys/kernel/security/integrity/ima/binary_runtime_measurements
+
+Then IMA ASCII measurement log has the following format:
+PCR TEMPLATE_DIGEST TEMPLATE ALG:EVENT_DIGEST EVENT_NAME EVENT_DATA
+
+PCR := Platform Configuration Register, in which the values are registered.
+       This is applicable if TPM chip is in use.
+TEMPLATE_DIGEST := Template digest of the IMA record.
+TEMPLATE := Template that registered the integrity value (e.g. ima-buf).
+ALG:EVENT_DIGEST = Algorithm to compute event digest, followed by digest of event data
+EVENT_NAME := Description of the event (e.g. 'table_load').
+EVENT_DATA := The event data to be measured.
+
+The DM target data measured by IMA subsystem can alternatively
+be queried from userspace by setting DM_IMA_MEASUREMENT_FLAG with
+DM_TABLE_STATUS_CMD.
+
+Supported Device States:
+========================
+Following device state changes will trigger IMA measurements.
+01. Table load
+02. Device resume
+03. Device remove
+04. Table clear
+05. Device rename
+
+01. Table load:
+---------------
+When a new table is loaded in a device's inactive table slot,
+the device information and target specific details from the
+targets in the table are measured.
+
+For instance, if a linear device is created with the following table entries,
+# dmsetup create linear1
+0 2 linear /dev/loop0 512
+2 2 linear /dev/loop0 512
+4 2 linear /dev/loop0 512
+6 2 linear /dev/loop0 512
+
+Then IMA ASCII measurement log will have an entry with:
+EVENT_NAME := table_load
+EVENT_DATA := [device_data];[target_data_row_1];[target_data_row_2];...[target_data_row_n];
+
+E.g.
+(converted from ASCII to text for readability)
+10 a8c5ff755561c7a28146389d1514c318592af49a ima-buf sha256:4d73481ecce5eadba8ab084640d85bb9ca899af4d0a122989252a76efadc5b72
+table_load
+name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=4;
+target_index=0,target_begin=0,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+target_index=1,target_begin=2,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+target_index=2,target_begin=4,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+target_index=3,target_begin=6,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+
+02. Device resume:
+------------------
+When a suspended device is resumed, the device information and a sha256 hash of the
+data from previous load of an active table are measured.
+
+For instance, if a linear device is resumed with the following command,
+#dmsetup resume linear1
+
+Then IMA ASCII measurement log will have an entry with:
+EVENT_NAME := device_resume
+EVENT_DATA := [device_data];active_table_hash=(sha256hash([device_data];[target_data_row_1];...[target_data_row_n]);
+              current_device_capacity=<N>;
+
+E.g.
+(converted from ASCII to text for readability)
+10 56c00cc062ffc24ccd9ac2d67d194af3282b934e ima-buf sha256:e7d12c03b958b4e0e53e7363a06376be88d98a1ac191fdbd3baf5e4b77f329b6
+device_resume
+name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=4;
+active_table_hash=4d73481ecce5eadba8ab084640d85bb9ca899af4d0a122989252a76efadc5b72;current_device_capacity=8;
+
+03. Device remove:
+------------------
+When a device is removed, the device information and a sha256 hash of the
+data from an active and inactive table are measured.
+
+For instance, if a linear device is removed with the following command,
+# dmsetup remove linear1
+
+Then IMA ASCII measurement log will have an entry with:
+EVENT_NAME := device_remove
+EVENT_DATA := [device_active_metadata];[device_inactive_metadata];
+              [active_table_hash=(sha256hash([device_active_metadata];[active_table_row_1];...[active_table_row_n]),
+              [inactive_table_hash=(sha256hash([device_inactive_metadata];[inactive_table_row_1];...[inactive_table_row_n]),
+              remove_all=[y|n];current_device_capacity=<N>;
+
+E.g
+(converted from ASCII to text for readability)
+10 499812b621b705061c4514d643894483e16d2619 ima-buf sha256:c3f26b02f09bf5b464925589454bdd4d354077ce430fd1e75c9e96ce29cd1cad
+device_remove
+device_active_metadata=name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=4;
+device_inactive_metadata=name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=2;
+active_table_hash=4d73481ecce5eadba8ab084640d85bb9ca899af4d0a122989252a76efadc5b72,
+inactive_table_hash=5596cc857b0e887fd0c5d58dc6382513284596b07f09fd37efae2da224bd521d,remove_all=n;
+current_device_capacity=8;
+
+
+04. Table clear:
+----------------
+When an inactive table is cleared from the device, the device information and a sha256 hash of the
+data from an inactive table are measured.
+
+For instance, if a linear device's inactive table is cleared with the following command,
+
+# dmsetup clear linear1
+
+Then IMA ASCII measurement log will have an entry with:
+EVENT_NAME := table_clear
+EVENT_DATA := [device_data];inactive_table_hash=(sha256hash([device_data];[inactive_table_row_1];...[inactive_table_row_n]);
+current_device_capacity=<N>;
+
+E.g.
+(converted from ASCII to text for readability)
+10 9c11e284d792875352d51c09f6643c96649484be ima-buf sha256:84b22b364ea4d8264fa33c38635c18ef448fa9077731fa7e5f969b1da2003ea4
+table_clear
+name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=2;
+inactive_table_hash=5596cc857b0e887fd0c5d58dc6382513284596b07f09fd37efae2da224bd521d;current_device_capacity=0;
+
+
+05. Device rename:
+------------------
+When an device's NAME or UUID is changed, the device information and the new NAME and UUID
+are measured.
+
+For instance, if a linear device's name is changed with the following command,
+
+#dmsetup rename linear1 linear=2
+Then IMA ASCII measurement log will have an entry with:
+EVENT_NAME := device_rename
+EVENT_DATA := [current_device_data];new_name=<new_name_value>;new_uuid=<new_uuid_value>;current_device_capacity=<N>;
+
+E.g 1:
+#dmsetup rename linear1 --setuuid 1234-5678
+
+IMA Log entry:
+(converted from ASCII to text for readability)
+10 7380ef4d1349fe1ebd74affa54e9fcc960e3cbf5 ima-buf sha256:9759e36a17a967ea43c1bf3455279395a40bd0401105ec5ad8edb9a52054efc7
+device_rename
+name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=1;new_name=linear1,new_uuid=1234-5678;current_device_capacity=2;
+
+E.g 2:
+# dmsetup rename linear1 linear=2
+10 092c8266fc36e44f74c59f123ecfe15310f249f4 ima-buf sha256:4cf8b85c81fa6fedaeb602b05019124dbbb0605dce58fcdeea56887a8a3874cd
+device_rename
+name=linear1,uuid=1234-5678,major=253,minor=0,minor_count=1,num_targets=1;new_name=linear\=2,new_uuid=1234-5678;current_device_capacity=2;
+
+
+Supported targets:
+==================
+Following targets are supported to measure their data using IMA.
+
+01. cache
+02. crypt
+03. integrity
+04. linear
+05. mirror
+06. multipath
+07. raid
+08. snapshot
+09. striped
+10. verity
+
+01. cache
+---------
+<<documenatation in progress>>
+
+02. crypt
+---------
+When a crypt target is loaded, then IMA ASCII measurement log will have an entry
+similar to the following, depicting what crypt attributes are measured in EVENT_DATA.
+
+(converted from ASCII to text for readability)
+10 fe3b80a35b155bd282df778e2625066c05fc068c ima-buf sha256:2d86ce9d6f16a4a97607318aa123ae816e0ceadefeea7903abf7f782f2cb78ad
+table_load
+name=test-crypt,uuid=,major=253,minor=0,minor_count=1,num_targets=1;
+target_index=0,target_begin=0,target_len=1953125,target_name=crypt,target_version=1.23.0,
+allow_discards=y,same_cpu=n,submit_from_crypt_cpus=n,no_read_workqueue=n,no_write_workqueue=n,
+iv_large_sectors=n,cipher_string=aes-xts-plain64,key_size=32,key_parts=1,key_extra_size=0,key_mac_size=0;
+
+03. integrity
+-------------
+<<documenatation in progress>>
+
+
+04. linear
+----------
+When a linear target is loaded, then IMA ASCII measurement log will have an entry
+similar to the following, depicting what linear attributes are measured in EVENT_DATA.
+
+(converted from ASCII to text for readability)
+10 a8c5ff755561c7a28146389d1514c318592af49a ima-buf sha256:4d73481ecce5eadba8ab084640d85bb9ca899af4d0a122989252a76efadc5b72
+table_load
+name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=4;
+target_index=0,target_begin=0,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+target_index=1,target_begin=2,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+target_index=2,target_begin=4,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+target_index=3,target_begin=6,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+
+05. mirror
+----------
+When a mirror target is loaded, then IMA ASCII measurement log will have an entry
+similar to the following, depicting what mirror attributes are measured in EVENT_DATA.
+
+(converted from ASCII to text for readability)
+10 90ff9113a00c367df823595dc347425ce3bfc50a ima-buf sha256:8da0678ed3bf616533573d9e61e5342f2bd16cb0b3145a08262641a743806c2e
+table_load
+name=test-mirror,uuid=,major=253,minor=4,minor_count=1,num_targets=1;
+target_index=0,target_begin=0,target_len=1953125,target_name=mirror,target_version=1.14.0,
+nr_mirrors=2,mirror_device_0=253:2,mirror_device_0_status=A,mirror_device_1=253:3,mirror_device_1_status=A,
+handle_errors=y,keep_log=n,log_type_status=;
+
+06. multipath
+-------------
+<<documenatation in progress>>
+
+07. raid
+--------
+When a raid target is loaded, then IMA ASCII measurement log will have an entry
+similar to the following, depicting what raid attributes are measured in EVENT_DATA.
+
+(converted from ASCII to text for readability)
+10 76cb30d0cd0fe099966f20f5c82e3a2ac29b21a0 ima-buf sha256:52250f20b27376fcfb348bdfa1e1cf5acfd6646e0f3ad1a72952cffd9f818753
+table_load
+name=test-raid1,uuid=,major=253,minor=2,minor_count=1,num_targets=1;
+target_index=0,target_begin=0,target_len=1953125,target_name=raid,target_version=1.15.1,
+raid_type=raid1,raid_disks=2,raid_state=idle,raid_device_0_status=A,raid_device_1_status=A;
+
+08. snapshot
+------------
+<<documenatation in progress>>
+
+09. striped
+-----------
+When a linear target is loaded, then IMA ASCII measurement log will have an entry
+similar to the following, depicting what linear attributes are measured in EVENT_DATA.
+
+(converted from ASCII to text for readability)
+10 7bd94fa8f799169b9f12d97b9dbdce4dc5509233 ima-buf sha256:0d148eda69887f7833f1a6042767b54359cd23b64fa941b9e1856879eee1f778
+table_load
+name=test-raid0,uuid=,major=253,minor=8,minor_count=1,num_targets=1;
+target_index=0,target_begin=0,target_len=7812096,target_name=striped,target_version=1.6.0,stripes=4,chunk_size=128,
+stripe_0_device_name=253:1,stripe_0_physical_start=0,stripe_0_status=A,
+stripe_1_device_name=253:3,stripe_1_physical_start=0,stripe_1_status=A,
+stripe_2_device_name=253:5,stripe_2_physical_start=0,stripe_2_status=A,
+stripe_3_device_name=253:7,stripe_3_physical_start=0,stripe_3_status=A;
+
+10. verity
+----------
+When a verity target is loaded, then IMA ASCII measurement log will have an entry
+similar to the following, depicting what verity attributes are measured in EVENT_DATA.
+
+(converted from ASCII to text for readability)
+10 fced5f575b140fc0efac302c88a635174cd663da ima-buf sha256:021370c1cc93929460b06922c606334fb1d7ea5ecf04f2384f3157a446894283
+table_load
+name=test-verity,uuid=,major=253,minor=2,minor_count=1,num_targets=1;
+target_index=0,target_begin=0,target_len=1953120,target_name=verity,target_version=1.8.0,hash_failed=V,
+verity_version=1,data_device_name=253:1,hash_device_name=253:0,verity_algorithm=sha256,
+root_digest=29cb87e60ce7b12b443ba6008266f3e41e93e403d7f298f8e3f316b29ff89c5e,
+salt=e48da609055204e89ae53b655ca2216dd983cf3cb829f34f63a297d106d53e2d,
+ignore_zero_blocks=n,check_at_most_once=n;
diff --git a/Documentation/admin-guide/device-mapper/index.rst b/Documentation/admin-guide/device-mapper/index.rst
index 6cf8adc86fa8..cde52cc09645 100644
--- a/Documentation/admin-guide/device-mapper/index.rst
+++ b/Documentation/admin-guide/device-mapper/index.rst
@@ -13,6 +13,7 @@ Device Mapper
     dm-dust
     dm-ebs
     dm-flakey
+    dm-ima
     dm-init
     dm-integrity
     dm-io
-- 
cgit v1.2.3


From 528b16bfc3ae5f11638e71b3b63a81f9999df727 Mon Sep 17 00:00:00 2001
From: Arne Welzel <arne.welzel@corelight.com>
Date: Sat, 14 Aug 2021 00:40:38 +0200
Subject: dm crypt: Avoid percpu_counter spinlock contention in
 crypt_page_alloc()

On systems with many cores using dm-crypt, heavy spinlock contention in
percpu_counter_compare() can be observed when the page allocation limit
for a given device is reached or close to be reached. This is due
to percpu_counter_compare() taking a spinlock to compute an exact
result on potentially many CPUs at the same time.

Switch to non-exact comparison of allocated and allowed pages by using
the value returned by percpu_counter_read_positive() to avoid taking
the percpu_counter spinlock.

This may over/under estimate the actual number of allocated pages by at
most (batch-1) * num_online_cpus().

Currently, batch is bounded by 32. The system on which this issue was
first observed has 256 CPUs and 512GB of RAM. With a 4k page size, this
change may over/under estimate by 31MB. With ~10G (2%) allowed dm-crypt
allocations, this seems an acceptable error. Certainly preferred over
running into the spinlock contention.

This behavior was reproduced on an EC2 c5.24xlarge instance with 96 CPUs
and 192GB RAM as follows, but can be provoked on systems with less CPUs
as well.

 * Disable swap
 * Tune vm settings to promote regular writeback
     $ echo 50 > /proc/sys/vm/dirty_expire_centisecs
     $ echo 25 > /proc/sys/vm/dirty_writeback_centisecs
     $ echo $((128 * 1024 * 1024)) > /proc/sys/vm/dirty_background_bytes

 * Create 8 dmcrypt devices based on files on a tmpfs
 * Create and mount an ext4 filesystem on each crypt devices
 * Run stress-ng --hdd 8 within one of above filesystems

Total %system usage collected from sysstat goes to ~35%. Write throughput
on the underlying loop device is ~2GB/s. perf profiling an individual
kworker kcryptd thread shows the following profile, indicating spinlock
contention in percpu_counter_compare():

    99.98%     0.00%  kworker/u193:46  [kernel.kallsyms]  [k] ret_from_fork
      |
      --ret_from_fork
        kthread
        worker_thread
        |
         --99.92%--process_one_work
            |
            |--80.52%--kcryptd_crypt
            |    |
            |    |--62.58%--mempool_alloc
            |    |  |
            |    |   --62.24%--crypt_page_alloc
            |    |     |
            |    |      --61.51%--__percpu_counter_compare
            |    |        |
            |    |         --61.34%--__percpu_counter_sum
            |    |           |
            |    |           |--58.68%--_raw_spin_lock_irqsave
            |    |           |  |
            |    |           |   --58.30%--native_queued_spin_lock_slowpath
            |    |           |
            |    |            --0.69%--cpumask_next
            |    |                |
            |    |                 --0.51%--_find_next_bit
            |    |
            |    |--10.61%--crypt_convert
            |    |          |
            |    |          |--6.05%--xts_crypt
            ...

After applying this patch and running the same test, %system usage is
lowered to ~7% and write throughput on the loop device increases
to ~2.7GB/s. perf report shows mempool_alloc() as ~8% rather than ~62%
in the profile and not hitting the percpu_counter() spinlock anymore.

    |--8.15%--mempool_alloc
    |    |
    |    |--3.93%--crypt_page_alloc
    |    |    |
    |    |     --3.75%--__alloc_pages
    |    |         |
    |    |          --3.62%--get_page_from_freelist
    |    |              |
    |    |               --3.22%--rmqueue_bulk
    |    |                   |
    |    |                    --2.59%--_raw_spin_lock
    |    |                      |
    |    |                       --2.57%--native_queued_spin_lock_slowpath
    |    |
    |     --3.05%--_raw_spin_lock_irqsave
    |               |
    |                --2.49%--native_queued_spin_lock_slowpath

Suggested-by: DJ Gregor <dj@corelight.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Arne Welzel <arne.welzel@corelight.com>
Fixes: 5059353df86e ("dm crypt: limit the number of allocated pages")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-crypt.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 80fdc42ce3c8..9d15872dbe40 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -2661,7 +2661,12 @@ static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data)
 	struct crypt_config *cc = pool_data;
 	struct page *page;
 
-	if (unlikely(percpu_counter_compare(&cc->n_allocated_pages, dm_crypt_pages_per_client) >= 0) &&
+	/*
+	 * Note, percpu_counter_read_positive() may over (and under) estimate
+	 * the current usage by at most (batch - 1) * num_online_cpus() pages,
+	 * but avoids potential spinlock contention of an exact result.
+	 */
+	if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) &&
 	    likely(gfp_mask & __GFP_NORETRY))
 		return NULL;
 
-- 
cgit v1.2.3


From 8f509fd4a53ffaf07feeef6dd48cc6bd060ca4f3 Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Fri, 13 Aug 2021 14:37:56 -0700
Subject: dm ima: prefix dm table hashes in ima log with hash algorithm

The active/inactive table hashes measured in the ima log do not contain
the information about hash algorithm.  This information is useful for the
attestation servers to recreate the hashes and compare them with the ones
present in the ima log to verify the table contents.

Prefix the table hashes in various DM events in ima log with the hash
algorithm used to compute those hashes.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-ima.c | 14 +++++++++++---
 drivers/md/dm-ima.h |  1 +
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/md/dm-ima.c b/drivers/md/dm-ima.c
index 91ea4a7202ab..d4184ff28cca 100644
--- a/drivers/md/dm-ima.c
+++ b/drivers/md/dm-ima.c
@@ -186,6 +186,11 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 	struct crypto_shash *tfm = NULL;
 	u8 *digest = NULL;
 	bool noio = false;
+	/*
+	 * In below hash_alg_prefix_len assignment +1 is for the additional char (':'),
+	 * when prefixing the hash value with the hash algorithm name. e.g. sha256:<hash_value>.
+	 */
+	const size_t hash_alg_prefix_len = strlen(DM_IMA_TABLE_HASH_ALG) + 1;
 
 	ima_buf = dm_ima_alloc(DM_IMA_MEASUREMENT_BUF_LEN, GFP_KERNEL, noio);
 	if (!ima_buf)
@@ -204,7 +209,7 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 	if (dm_ima_alloc_and_copy_device_data(table->md, &device_data_buf, num_targets, noio))
 		goto error;
 
-	tfm = crypto_alloc_shash("sha256", 0, 0);
+	tfm = crypto_alloc_shash(DM_IMA_TABLE_HASH_ALG, 0, 0);
 	if (IS_ERR(tfm))
 		goto error;
 
@@ -315,12 +320,15 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 	if (r < 0)
 		goto error;
 
-	digest_buf = dm_ima_alloc((digest_size*2)+1, GFP_KERNEL, noio);
+	digest_buf = dm_ima_alloc((digest_size*2) + hash_alg_prefix_len + 1, GFP_KERNEL, noio);
+
 	if (!digest_buf)
 		goto error;
 
+	snprintf(digest_buf, hash_alg_prefix_len + 1, "%s:", DM_IMA_TABLE_HASH_ALG);
+
 	for (i = 0; i < digest_size; i++)
-		snprintf((digest_buf+(i*2)), 3, "%02x", digest[i]);
+		snprintf((digest_buf + hash_alg_prefix_len + (i*2)), 3, "%02x", digest[i]);
 
 	if (table->md->ima.active_table.hash != table->md->ima.inactive_table.hash)
 		kfree(table->md->ima.inactive_table.hash);
diff --git a/drivers/md/dm-ima.h b/drivers/md/dm-ima.h
index 6e6f18bf05b4..0731a51565d6 100644
--- a/drivers/md/dm-ima.h
+++ b/drivers/md/dm-ima.h
@@ -16,6 +16,7 @@
 #define DM_IMA_TARGET_METADATA_BUF_LEN	128
 #define DM_IMA_TARGET_DATA_BUF_LEN	2048
 #define DM_IMA_DEVICE_CAPACITY_BUF_LEN	128
+#define DM_IMA_TABLE_HASH_ALG		"sha256"
 
 #ifdef CONFIG_IMA
 
-- 
cgit v1.2.3


From dc7b79cc2466805855f554e5f567ea9222b6e33a Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Fri, 13 Aug 2021 14:37:57 -0700
Subject: dm ima: add version info to dm related events in ima log

The DM events present in the ima log contain various attributes in the
key=value format.  The attributes' names/values may change in future,
and new attributes may also get added.  The attestation server needs
some versioning to determine which attributes are supported and are
expected in the ima log.

Add version information to the DM events present in the ima log to
help attestation servers to correctly process the attributes across
different versions.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-ima.c | 60 ++++++++++++++++++++++++++++++++++++++++++-----------
 drivers/md/dm-ima.h |  9 ++++++++
 2 files changed, 57 insertions(+), 12 deletions(-)

diff --git a/drivers/md/dm-ima.c b/drivers/md/dm-ima.c
index d4184ff28cca..22faf0698d09 100644
--- a/drivers/md/dm-ima.c
+++ b/drivers/md/dm-ima.c
@@ -168,6 +168,7 @@ static int dm_ima_alloc_and_copy_capacity_str(struct mapped_device *md, char **c
 void dm_ima_reset_data(struct mapped_device *md)
 {
 	memset(&(md->ima), 0, sizeof(md->ima));
+	md->ima.dm_version_str_len = strlen(DM_IMA_VERSION_STR);
 }
 
 /*
@@ -223,6 +224,9 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 	if (r)
 		goto error;
 
+	memcpy(ima_buf + l, DM_IMA_VERSION_STR, table->md->ima.dm_version_str_len);
+	l += table->md->ima.dm_version_str_len;
+
 	device_data_buf_len = strlen(device_data_buf);
 	memcpy(ima_buf + l, device_data_buf, device_data_buf_len);
 	l += device_data_buf_len;
@@ -280,6 +284,9 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 			 * prefix, so that multiple records from the same table_load for
 			 * a given device can be linked together.
 			 */
+			memcpy(ima_buf + l, DM_IMA_VERSION_STR, table->md->ima.dm_version_str_len);
+			l += table->md->ima.dm_version_str_len;
+
 			memcpy(ima_buf + l, device_data_buf, device_data_buf_len);
 			l += device_data_buf_len;
 
@@ -367,6 +374,7 @@ void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
 	unsigned int active_len = strlen(active), capacity_len = 0;
 	unsigned int l = 0;
 	bool noio = true;
+	bool nodata = true;
 	int r;
 
 	device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
@@ -377,6 +385,9 @@ void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
 	if (r)
 		goto error;
 
+	memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
+	l += md->ima.dm_version_str_len;
+
 	if (swap) {
 		if (md->ima.active_table.hash != md->ima.inactive_table.hash)
 			kfree(md->ima.active_table.hash);
@@ -412,8 +423,11 @@ void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
 	}
 
 	if (md->ima.active_table.device_metadata) {
-		l = md->ima.active_table.device_metadata_len;
-		memcpy(device_table_data, md->ima.active_table.device_metadata, l);
+		memcpy(device_table_data + l, md->ima.active_table.device_metadata,
+		       md->ima.active_table.device_metadata_len);
+		l += md->ima.active_table.device_metadata_len;
+
+		nodata = false;
 	}
 
 	if (md->ima.active_table.hash) {
@@ -426,16 +440,18 @@ void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
 
 		memcpy(device_table_data + l, ";", 1);
 		l++;
+
+		nodata = false;
 	}
 
-	if (!l) {
+	if (nodata) {
 		r = dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio);
 		if (r)
 			goto error;
 
 		scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
-			  "name=%s,uuid=%s;device_resume=no_data;",
-			  dev_name, dev_uuid);
+			  "%sname=%s,uuid=%s;device_resume=no_data;",
+			  DM_IMA_VERSION_STR, dev_name, dev_uuid);
 		l += strlen(device_table_data);
 
 	}
@@ -472,6 +488,7 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
 	unsigned int capacity_len = 0;
 	unsigned int l = 0;
 	bool noio = true;
+	bool nodata = true;
 	int r;
 
 	device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN*2, GFP_KERNEL, noio);
@@ -484,6 +501,9 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
 		goto exit;
 	}
 
+	memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
+	l += md->ima.dm_version_str_len;
+
 	if (md->ima.active_table.device_metadata) {
 		memcpy(device_table_data + l, device_active_str, device_active_len);
 		l += device_active_len;
@@ -491,6 +511,8 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
 		memcpy(device_table_data + l, md->ima.active_table.device_metadata,
 		       md->ima.active_table.device_metadata_len);
 		l += md->ima.active_table.device_metadata_len;
+
+		nodata = false;
 	}
 
 	if (md->ima.inactive_table.device_metadata) {
@@ -500,6 +522,8 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
 		memcpy(device_table_data + l, md->ima.inactive_table.device_metadata,
 		       md->ima.inactive_table.device_metadata_len);
 		l += md->ima.inactive_table.device_metadata_len;
+
+		nodata = false;
 	}
 
 	if (md->ima.active_table.hash) {
@@ -512,6 +536,8 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
 
 		memcpy(device_table_data + l, ",", 1);
 		l++;
+
+		nodata = false;
 	}
 
 	if (md->ima.inactive_table.hash) {
@@ -524,19 +550,21 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
 
 		memcpy(device_table_data + l, ",", 1);
 		l++;
+
+		nodata = false;
 	}
 	/*
 	 * In case both active and inactive tables, and corresponding
 	 * device metadata is cleared/missing - record the name and uuid
 	 * in IMA measurements.
 	 */
-	if (!l) {
+	if (nodata) {
 		if (dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio))
 			goto error;
 
 		scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
-			  "name=%s,uuid=%s;device_remove=no_data;",
-			  dev_name, dev_uuid);
+			  "%sname=%s,uuid=%s;device_remove=no_data;",
+			  DM_IMA_VERSION_STR, dev_name, dev_uuid);
 		l += strlen(device_table_data);
 	}
 
@@ -582,6 +610,7 @@ void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map)
 	char inactive_str[] = "inactive_table_hash=";
 	unsigned int inactive_len = strlen(inactive_str);
 	bool noio = true;
+	bool nodata = true;
 	int r;
 
 	device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
@@ -592,6 +621,9 @@ void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map)
 	if (r)
 		goto error1;
 
+	memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
+	l += md->ima.dm_version_str_len;
+
 	if (md->ima.inactive_table.device_metadata_len &&
 	    md->ima.inactive_table.hash_len) {
 		memcpy(device_table_data + l, md->ima.inactive_table.device_metadata,
@@ -608,14 +640,17 @@ void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map)
 
 		memcpy(device_table_data + l, ";", 1);
 		l++;
+
+		nodata = false;
 	}
 
-	if (!l) {
+	if (nodata) {
 		if (dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio))
 			goto error2;
 
 		scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
-			  "name=%s,uuid=%s;table_clear=no_data;", dev_name, dev_uuid);
+			  "%sname=%s,uuid=%s;table_clear=no_data;",
+			   DM_IMA_VERSION_STR, dev_name, dev_uuid);
 		l += strlen(device_table_data);
 	}
 
@@ -694,8 +729,9 @@ void dm_ima_measure_on_device_rename(struct mapped_device *md)
 	md->ima.active_table.device_metadata = new_device_data;
 	md->ima.active_table.device_metadata_len = strlen(new_device_data);
 
-	scnprintf(combined_device_data, DM_IMA_DEVICE_BUF_LEN * 2, "%snew_name=%s,new_uuid=%s;%s",
-		  old_device_data, new_dev_name, new_dev_uuid, capacity_str);
+	scnprintf(combined_device_data, DM_IMA_DEVICE_BUF_LEN * 2,
+		  "%s%snew_name=%s,new_uuid=%s;%s", DM_IMA_VERSION_STR, old_device_data,
+		  new_dev_name, new_dev_uuid, capacity_str);
 
 	dm_ima_measure_data("device_rename", combined_device_data, strlen(combined_device_data),
 			    noio);
diff --git a/drivers/md/dm-ima.h b/drivers/md/dm-ima.h
index 0731a51565d6..b8c3b614670b 100644
--- a/drivers/md/dm-ima.h
+++ b/drivers/md/dm-ima.h
@@ -18,6 +18,14 @@
 #define DM_IMA_DEVICE_CAPACITY_BUF_LEN	128
 #define DM_IMA_TABLE_HASH_ALG		"sha256"
 
+#define __dm_ima_stringify(s) #s
+#define __dm_ima_str(s) __dm_ima_stringify(s)
+
+#define DM_IMA_VERSION_STR "dm_version="	\
+	__dm_ima_str(DM_VERSION_MAJOR) "."	\
+	__dm_ima_str(DM_VERSION_MINOR) "."	\
+	__dm_ima_str(DM_VERSION_PATCHLEVEL) ";"
+
 #ifdef CONFIG_IMA
 
 struct dm_ima_device_table_metadata {
@@ -46,6 +54,7 @@ struct dm_ima_device_table_metadata {
 struct dm_ima_measurements {
 	struct dm_ima_device_table_metadata active_table;
 	struct dm_ima_device_table_metadata inactive_table;
+	unsigned int dm_version_str_len;
 };
 
 void dm_ima_reset_data(struct mapped_device *md);
-- 
cgit v1.2.3


From 9c2adfa6ba134efaf0bdeb15f76f99e9bcffb903 Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Fri, 13 Aug 2021 14:37:58 -0700
Subject: dm ima: prefix ima event name related to device mapper with dm_

The event names for the DM events recorded in the ima log do not contain
any information to indicate the events are part of the DM devices/targets.

Prefix the event names for DM events with "dm_" to indicate that they
are part of device-mapper.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Suggested-by: Thore Sommer <public@thson.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-ima.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/drivers/md/dm-ima.c b/drivers/md/dm-ima.c
index 22faf0698d09..3fd69ab12a8e 100644
--- a/drivers/md/dm-ima.c
+++ b/drivers/md/dm-ima.c
@@ -192,6 +192,7 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 	 * when prefixing the hash value with the hash algorithm name. e.g. sha256:<hash_value>.
 	 */
 	const size_t hash_alg_prefix_len = strlen(DM_IMA_TABLE_HASH_ALG) + 1;
+	char table_load_event_name[] = "dm_table_load";
 
 	ima_buf = dm_ima_alloc(DM_IMA_MEASUREMENT_BUF_LEN, GFP_KERNEL, noio);
 	if (!ima_buf)
@@ -271,7 +272,7 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 		 * targets by prefixing the device metadata again.
 		 */
 		if (unlikely(cur_total_buf_len >= DM_IMA_MEASUREMENT_BUF_LEN)) {
-			dm_ima_measure_data("table_load", ima_buf, l, noio);
+			dm_ima_measure_data(table_load_event_name, ima_buf, l, noio);
 			r = crypto_shash_update(shash, (const u8 *)ima_buf, l);
 			if (r < 0)
 				goto error;
@@ -280,8 +281,8 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 			l = 0;
 
 			/*
-			 * Each new "table_load" entry in IMA log should have device data
-			 * prefix, so that multiple records from the same table_load for
+			 * Each new "dm_table_load" entry in IMA log should have device data
+			 * prefix, so that multiple records from the same "dm_table_load" for
 			 * a given device can be linked together.
 			 */
 			memcpy(ima_buf + l, DM_IMA_VERSION_STR, table->md->ima.dm_version_str_len);
@@ -292,7 +293,7 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 
 			/*
 			 * If this iteration of the for loop turns out to be the last target
-			 * in the table, dm_ima_measure_data("table_load", ...) doesn't need
+			 * in the table, dm_ima_measure_data("dm_table_load", ...) doesn't need
 			 * to be called again, just the hash needs to be finalized.
 			 * "last_target_measured" tracks this state.
 			 */
@@ -311,7 +312,7 @@ void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_fl
 	}
 
 	if (!last_target_measured) {
-		dm_ima_measure_data("table_load", ima_buf, l, noio);
+		dm_ima_measure_data(table_load_event_name, ima_buf, l, noio);
 
 		r = crypto_shash_update(shash, (const u8 *)ima_buf, l);
 		if (r < 0)
@@ -460,7 +461,7 @@ void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
 	memcpy(device_table_data + l, capacity_str, capacity_len);
 	l += capacity_len;
 
-	dm_ima_measure_data("device_resume", device_table_data, l, noio);
+	dm_ima_measure_data("dm_device_resume", device_table_data, l, noio);
 
 	kfree(dev_name);
 	kfree(dev_uuid);
@@ -577,7 +578,7 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
 	memcpy(device_table_data + l, capacity_str, capacity_len);
 	l += capacity_len;
 
-	dm_ima_measure_data("device_remove", device_table_data, l, noio);
+	dm_ima_measure_data("dm_device_remove", device_table_data, l, noio);
 
 error:
 	kfree(device_table_data);
@@ -658,7 +659,7 @@ void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map)
 	memcpy(device_table_data + l, capacity_str, capacity_len);
 	l += capacity_len;
 
-	dm_ima_measure_data("table_clear", device_table_data, l, noio);
+	dm_ima_measure_data("dm_table_clear", device_table_data, l, noio);
 
 	if (new_map) {
 		if (md->ima.inactive_table.hash &&
@@ -733,7 +734,7 @@ void dm_ima_measure_on_device_rename(struct mapped_device *md)
 		  "%s%snew_name=%s,new_uuid=%s;%s", DM_IMA_VERSION_STR, old_device_data,
 		  new_dev_name, new_dev_uuid, capacity_str);
 
-	dm_ima_measure_data("device_rename", combined_device_data, strlen(combined_device_data),
+	dm_ima_measure_data("dm_device_rename", combined_device_data, strlen(combined_device_data),
 			    noio);
 
 	goto exit;
-- 
cgit v1.2.3


From f1cd6cb24b6b3cd95227e8016d092310a4015e96 Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Fri, 13 Aug 2021 14:37:59 -0700
Subject: dm ima: add a warning in dm_init if duplicate ima events are not
 measured

The end-users of DM devices/targets may remove and re-create the same
device multiple times.  IMA does not measure such duplicate events if the
configuration CONFIG_IMA_DISABLE_HTABLE is set to 'n'.
To avoid confusion, the end-users need some indication on the client
if that configuration option is disabled.

Add a one-time warning during dm_init() if CONFIG_IMA_DISABLE_HTABLE
is set to 'n', to notify the end-users that duplicate events will not
be measured in the ima log. Also cleanup some whitespace in dm_init().

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 33e55ac9ec65..84e9145b1714 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -262,9 +262,13 @@ static void (*_exits[])(void) = {
 static int __init dm_init(void)
 {
 	const int count = ARRAY_SIZE(_inits);
-
 	int r, i;
 
+#if (IS_ENABLED(CONFIG_IMA) && !IS_ENABLED(CONFIG_IMA_DISABLE_HTABLE))
+	DMWARN("CONFIG_IMA_DISABLE_HTABLE is disabled."
+	       " Duplicate IMA measurements will not be recorded in the IMA log.");
+#endif
+
 	for (i = 0; i < count; i++) {
 		r = _inits[i]();
 		if (r)
@@ -272,8 +276,7 @@ static int __init dm_init(void)
 	}
 
 	return 0;
-
-      bad:
+bad:
 	while (i--)
 		_exits[i]();
 
-- 
cgit v1.2.3


From 33ace4ca125315d7f4f2b022bf6c83dfade8f9d8 Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Fri, 13 Aug 2021 14:38:00 -0700
Subject: dm ima: update dm target attributes for ima measurements

Certain DM targets ('integrity', 'multipath', 'verity') need to update the
way their attributes are recorded in the ima log, so that the attestation
servers can interpret the data correctly and decide if the devices
meet the attestation requirements.  For instance, the "mode=%c" attribute
in the 'integrity' target is measured twice, the 'verity' target is
missing the attribute "root_hash_sig_key_desc=%s", and the 'multipath'
target needs to index the attributes properly.

Update 'integrity' target to remove the duplicate measurement of
the attribute "mode=%c".  Add "root_hash_sig_key_desc=%s" attribute
for the 'verity' target.  Index various attributes in 'multipath'
target.  Also, add "nr_priority_groups=%u" attribute to 'multipath'
target to record the number of priority groups.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Suggested-by: Thore Sommer <public@thson.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-integrity.c     |  1 -
 drivers/md/dm-mpath.c         | 26 ++++++++++++++++++--------
 drivers/md/dm-verity-target.c |  2 ++
 3 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index 40f8116c8e44..6e0b2f2f5911 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -3328,7 +3328,6 @@ static void dm_integrity_status(struct dm_target *ti, status_type_t type,
 		DMEMIT(",journal_sectors=%u", ic->initial_sectors - SB_SECTORS);
 		DMEMIT(",interleave_sectors=%u", 1U << ic->sb->log2_interleave_sectors);
 		DMEMIT(",buffer_sectors=%u", 1U << ic->log2_buffer_sectors);
-		DMEMIT(",mode=%c", ic->mode);
 		DMEMIT(";");
 		break;
 	}
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index c3c514a9edbb..694aaca4eea2 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1790,7 +1790,7 @@ static void multipath_resume(struct dm_target *ti)
 static void multipath_status(struct dm_target *ti, status_type_t type,
 			     unsigned status_flags, char *result, unsigned maxlen)
 {
-	int sz = 0;
+	int sz = 0, pg_counter, pgpath_counter;
 	unsigned long flags;
 	struct multipath *m = ti->private;
 	struct priority_group *pg;
@@ -1906,7 +1906,12 @@ static void multipath_status(struct dm_target *ti, status_type_t type,
 		break;
 
 	case STATUSTYPE_IMA:
+		sz = 0; /*reset the result pointer*/
+
 		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		DMEMIT(",nr_priority_groups=%u", m->nr_priority_groups);
+
+		pg_counter = 0;
 		list_for_each_entry(pg, &m->priority_groups, list) {
 			if (pg->bypassed)
 				state = 'D';	/* Disabled */
@@ -1914,21 +1919,26 @@ static void multipath_status(struct dm_target *ti, status_type_t type,
 				state = 'A';	/* Currently Active */
 			else
 				state = 'E';	/* Enabled */
-			DMEMIT(",pg_state=%c", state);
-			DMEMIT(",nr_pgpaths=%u", pg->nr_pgpaths);
-			DMEMIT(",path_selector_name=%s", pg->ps.type->name);
+			DMEMIT(",pg_state_%d=%c", pg_counter, state);
+			DMEMIT(",nr_pgpaths_%d=%u", pg_counter, pg->nr_pgpaths);
+			DMEMIT(",path_selector_name_%d=%s", pg_counter, pg->ps.type->name);
 
+			pgpath_counter = 0;
 			list_for_each_entry(p, &pg->pgpaths, list) {
-				DMEMIT(",path_name=%s,is_active=%c,fail_count=%u",
-				       p->path.dev->name, p->is_active ? 'A' : 'F',
-				       p->fail_count);
+				DMEMIT(",path_name_%d_%d=%s,is_active_%d_%d=%c,fail_count_%d_%d=%u",
+				       pg_counter, pgpath_counter, p->path.dev->name,
+				       pg_counter, pgpath_counter, p->is_active ? 'A' : 'F',
+				       pg_counter, pgpath_counter, p->fail_count);
 				if (pg->ps.type->status) {
-					DMEMIT(",path_selector_status=");
+					DMEMIT(",path_selector_status_%d_%d=",
+					       pg_counter, pgpath_counter);
 					sz += pg->ps.type->status(&pg->ps, &p->path,
 								  type, result + sz,
 								  maxlen - sz);
 				}
+				pgpath_counter++;
 			}
+			pg_counter++;
 		}
 		DMEMIT(";");
 		break;
diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index bfefa100c265..22a5ac82446a 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -794,6 +794,8 @@ static void verity_status(struct dm_target *ti, status_type_t type,
 
 		DMEMIT(",ignore_zero_blocks=%c", v->zero_digest ? 'y' : 'n');
 		DMEMIT(",check_at_most_once=%c", v->validated_blocks ? 'y' : 'n');
+		if (v->signature_key_desc)
+			DMEMIT(",root_hash_sig_key_desc=%s", v->signature_key_desc);
 
 		if (v->mode != DM_VERITY_MODE_EIO) {
 			DMEMIT(",verity_mode=");
-- 
cgit v1.2.3


From 17bfa96851e02968950dfbbce76ca552e7b713a2 Mon Sep 17 00:00:00 2001
From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Date: Fri, 13 Aug 2021 14:38:01 -0700
Subject: dm ima: update dm documentation for ima measurement support

The ima documentation for measuring DM targets (dm-ima.rst) is
missing the attribute information for the targets - 'cache', 'integrity',
'multipath', and 'snapshot'.  It is also missing the grammar for
various DM events and targets, which can help the attestation servers
to determine what data to expect for a given DM device.  Further,
the documentation needs to be updated to incorporate code changes
made to DM ima events and targets as part of this patch series.  For
instance, prefixing the event names with "dm_", adding the DM version to
events, prefixing the table hashes in the ima log with the
hash algorithm etc.  There are warnings reported by 'make htmldocs' on
dm-ima.rst, which need to be fixed.  And lastly, the expected behavior
needs to be documented when the configuration CONFIG_IMA_DISABLE_HTABLE
is disabled.

Update the documentation to add examples for 'cache', 'integrity',
'multipath', and 'snapshot' targets.  Add the grammar for
various DM events and targets in Backus Naur form,
so that the attestation servers can interpret and act on the ima
measurements for DM target.  Fix htmldocs warnings in dm-ima.rst.  Update
the documentation to be consistent with the code changes that are part of
this patch series.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 Documentation/admin-guide/device-mapper/dm-ima.rst | 827 +++++++++++++++------
 1 file changed, 618 insertions(+), 209 deletions(-)

diff --git a/Documentation/admin-guide/device-mapper/dm-ima.rst b/Documentation/admin-guide/device-mapper/dm-ima.rst
index 41894112ff26..a4aa50a828e0 100644
--- a/Documentation/admin-guide/device-mapper/dm-ima.rst
+++ b/Documentation/admin-guide/device-mapper/dm-ima.rst
@@ -26,9 +26,10 @@ fully trusting the system with business-critical data/workload.
 IMA kernel subsystem provides the necessary functionality for
 device mapper to measure the state and configuration of
 various block devices -
-  - BY device mapper itself, from within the kernel,
-  - in a tamper resistant way,
-  - and re-measured - triggered on state/configuration change.
+
+- by device mapper itself, from within the kernel,
+- in a tamper resistant way,
+- and re-measured - triggered on state/configuration change.
 
 Setting the IMA Policy:
 =======================
@@ -36,271 +37,679 @@ For IMA to measure the data on a given system, the IMA policy on the
 system needs to be updated to have following line, and the system needs
 to be restarted for the measurements to take effect.
 
-/etc/ima/ima-policy
- measure func=CRITICAL_DATA label=device-mapper template=ima-buf
+::
+
+ /etc/ima/ima-policy
+    measure func=CRITICAL_DATA label=device-mapper template=ima-buf
 
 The measurements will be reflected in the IMA logs, which are located at:
 
-/sys/kernel/security/integrity/ima/ascii_runtime_measurements
-/sys/kernel/security/integrity/ima/binary_runtime_measurements
+::
+
+ /sys/kernel/security/integrity/ima/ascii_runtime_measurements
+ /sys/kernel/security/integrity/ima/binary_runtime_measurements
 
 Then IMA ASCII measurement log has the following format:
-PCR TEMPLATE_DIGEST TEMPLATE ALG:EVENT_DIGEST EVENT_NAME EVENT_DATA
 
-PCR := Platform Configuration Register, in which the values are registered.
+::
+
+ <PCR> <TEMPLATE_DATA_DIGEST> <TEMPLATE_NAME> <TEMPLATE_DATA>
+
+ PCR := Platform Configuration Register, in which the values are registered.
        This is applicable if TPM chip is in use.
-TEMPLATE_DIGEST := Template digest of the IMA record.
-TEMPLATE := Template that registered the integrity value (e.g. ima-buf).
-ALG:EVENT_DIGEST = Algorithm to compute event digest, followed by digest of event data
-EVENT_NAME := Description of the event (e.g. 'table_load').
-EVENT_DATA := The event data to be measured.
 
-The DM target data measured by IMA subsystem can alternatively
-be queried from userspace by setting DM_IMA_MEASUREMENT_FLAG with
-DM_TABLE_STATUS_CMD.
+ TEMPLATE_DATA_DIGEST := Template data digest of the IMA record.
+ TEMPLATE_NAME := Template name that registered the integrity value (e.g. ima-buf).
+
+ TEMPLATE_DATA := <ALG> ":" <EVENT_DIGEST> <EVENT_NAME> <EVENT_DATA>
+                  It contains data for the specific event to be measured,
+                  in a given template data format.
+
+ ALG := Algorithm to compute event digest
+ EVENT_DIGEST := Digest of the event data
+ EVENT_NAME := Description of the event (e.g. 'dm_table_load').
+ EVENT_DATA := The event data to be measured.
+
+|
+
+| *NOTE #1:*
+| The DM target data measured by IMA subsystem can alternatively
+ be queried from userspace by setting DM_IMA_MEASUREMENT_FLAG with
+ DM_TABLE_STATUS_CMD.
+
+|
+
+| *NOTE #2:*
+| The Kernel configuration CONFIG_IMA_DISABLE_HTABLE allows measurement of duplicate records.
+| To support recording duplicate IMA events in the IMA log, the Kernel needs to be configured with
+ CONFIG_IMA_DISABLE_HTABLE=y.
 
 Supported Device States:
 ========================
-Following device state changes will trigger IMA measurements.
-01. Table load
-02. Device resume
-03. Device remove
-04. Table clear
-05. Device rename
-
-01. Table load:
+Following device state changes will trigger IMA measurements:
+
+ 1. Table load
+ #. Device resume
+ #. Device remove
+ #. Table clear
+ #. Device rename
+
+1. Table load:
 ---------------
 When a new table is loaded in a device's inactive table slot,
 the device information and target specific details from the
 targets in the table are measured.
 
-For instance, if a linear device is created with the following table entries,
-# dmsetup create linear1
-0 2 linear /dev/loop0 512
-2 2 linear /dev/loop0 512
-4 2 linear /dev/loop0 512
-6 2 linear /dev/loop0 512
-
-Then IMA ASCII measurement log will have an entry with:
-EVENT_NAME := table_load
-EVENT_DATA := [device_data];[target_data_row_1];[target_data_row_2];...[target_data_row_n];
-
-E.g.
-(converted from ASCII to text for readability)
-10 a8c5ff755561c7a28146389d1514c318592af49a ima-buf sha256:4d73481ecce5eadba8ab084640d85bb9ca899af4d0a122989252a76efadc5b72
-table_load
-name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=4;
-target_index=0,target_begin=0,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
-target_index=1,target_begin=2,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
-target_index=2,target_begin=4,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
-target_index=3,target_begin=6,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
-
-02. Device resume:
+The IMA measurement log has the following format for 'dm_table_load':
+
+::
+
+ EVENT_NAME := "dm_table_load"
+ EVENT_DATA := <dm_version_str> ";" <device_metadata> ";" <table_load_data>
+
+ dm_version_str := "dm_version=" <N> "." <N> "." <N>
+                  Same as Device Mapper driver version.
+ device_metadata := <device_name> "," <device_uuid> "," <device_major> "," <device_minor> ","
+                   <minor_count> "," <num_device_targets> ";"
+
+ device_name := "name=" <dm-device-name>
+ device_uuid := "uuid=" <dm-device-uuid>
+ device_major := "major=" <N>
+ device_minor := "minor=" <N>
+ minor_count := "minor_count=" <N>
+ num_device_targets := "num_targets=" <N>
+ dm-device-name := Name of the device. If it contains special characters like '\', ',', ';',
+                   they are prefixed with '\'.
+ dm-device-uuid := UUID of the device. If it contains special characters like '\', ',', ';',
+                   they are prefixed with '\'.
+
+ table_load_data := <target_data>
+                    Represents the data (as name=value pairs) from various targets in the table,
+                    which is being loaded into the DM device's inactive table slot.
+ target_data := <target_data_row> | <target_data><target_data_row>
+
+ target_data_row := <target_index> "," <target_begin> "," <target_len> "," <target_name> ","
+                    <target_version> "," <target_attributes> ";"
+ target_index := "target_index=" <N>
+                 Represents nth target in the table (from 0 to N-1 targets specified in <num_device_targets>)
+                 If all the data for N targets doesn't fit in the given buffer - then the data that fits
+                 in the buffer (say from target 0 to x) is measured in a given IMA event.
+                 The remaining data from targets x+1 to N-1 is measured in the subsequent IMA events,
+                 with the same format as that of 'dm_table_load'
+                 i.e. <dm_version_str> ";" <device_metadata> ";" <table_load_data>.
+
+ target_begin := "target_begin=" <N>
+ target_len := "target_len=" <N>
+ target_name := Name of the target. 'linear', 'crypt', 'integrity' etc.
+                The targets that are supported for IMA measurements are documented below in the
+                'Supported targets' section.
+ target_version := "target_version=" <N> "." <N> "." <N>
+ target_attributes := Data containing comma separated list of name=value pairs of target specific attributes.
+
+ For instance, if a linear device is created with the following table entries,
+  # dmsetup create linear1
+  0 2 linear /dev/loop0 512
+  2 2 linear /dev/loop0 512
+  4 2 linear /dev/loop0 512
+  6 2 linear /dev/loop0 512
+
+ Then IMA ASCII measurement log will have the following entry:
+ (converted from ASCII to text for readability)
+
+ 10 a8c5ff755561c7a28146389d1514c318592af49a ima-buf sha256:4d73481ecce5eadba8ab084640d85bb9ca899af4d0a122989252a76efadc5b72
+ dm_table_load
+ dm_version=4.45.0;
+ name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=4;
+ target_index=0,target_begin=0,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+ target_index=1,target_begin=2,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+ target_index=2,target_begin=4,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+ target_index=3,target_begin=6,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
+
+2. Device resume:
 ------------------
-When a suspended device is resumed, the device information and a sha256 hash of the
+When a suspended device is resumed, the device information and the hash of the
 data from previous load of an active table are measured.
 
-For instance, if a linear device is resumed with the following command,
-#dmsetup resume linear1
+The IMA measurement log has the following format for 'dm_device_resume':
 
-Then IMA ASCII measurement log will have an entry with:
-EVENT_NAME := device_resume
-EVENT_DATA := [device_data];active_table_hash=(sha256hash([device_data];[target_data_row_1];...[target_data_row_n]);
-              current_device_capacity=<N>;
+::
 
-E.g.
-(converted from ASCII to text for readability)
-10 56c00cc062ffc24ccd9ac2d67d194af3282b934e ima-buf sha256:e7d12c03b958b4e0e53e7363a06376be88d98a1ac191fdbd3baf5e4b77f329b6
-device_resume
-name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=4;
-active_table_hash=4d73481ecce5eadba8ab084640d85bb9ca899af4d0a122989252a76efadc5b72;current_device_capacity=8;
+ EVENT_NAME := "dm_device_resume"
+ EVENT_DATA := <dm_version_str> ";" <device_metadata> ";" <active_table_hash> ";" <current_device_capacity> ";"
 
-03. Device remove:
-------------------
-When a device is removed, the device information and a sha256 hash of the
-data from an active and inactive table are measured.
+ dm_version_str := As described in the 'Table load' section above.
+ device_metadata := As described in the 'Table load' section above.
+ active_table_hash := "active_table_hash=" <table_hash_alg> ":" <table_hash>
+                      Rerpresents the hash of the IMA data being measured for the
+                      active table for the device.
+ table_hash_alg := Algorithm used to compute the hash.
+ table_hash := Hash of the (<dm_version_str> ";" <device_metadata> ";" <table_load_data> ";")
+               as described in the 'dm_table_load' above.
+               Note: If the table_load data spans across multiple IMA 'dm_table_load'
+               events for a given device, the hash is computed combining all the event data
+               i.e. (<dm_version_str> ";" <device_metadata> ";" <table_load_data> ";")
+               across all those events.
+ current_device_capacity := "current_device_capacity=" <N>
 
-For instance, if a linear device is removed with the following command,
-# dmsetup remove linear1
+ For instance, if a linear device is resumed with the following command,
+ #dmsetup resume linear1
 
-Then IMA ASCII measurement log will have an entry with:
-EVENT_NAME := device_remove
-EVENT_DATA := [device_active_metadata];[device_inactive_metadata];
-              [active_table_hash=(sha256hash([device_active_metadata];[active_table_row_1];...[active_table_row_n]),
-              [inactive_table_hash=(sha256hash([device_inactive_metadata];[inactive_table_row_1];...[inactive_table_row_n]),
-              remove_all=[y|n];current_device_capacity=<N>;
+ then IMA ASCII measurement log will have an entry with:
+ (converted from ASCII to text for readability)
 
-E.g
-(converted from ASCII to text for readability)
-10 499812b621b705061c4514d643894483e16d2619 ima-buf sha256:c3f26b02f09bf5b464925589454bdd4d354077ce430fd1e75c9e96ce29cd1cad
-device_remove
-device_active_metadata=name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=4;
-device_inactive_metadata=name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=2;
-active_table_hash=4d73481ecce5eadba8ab084640d85bb9ca899af4d0a122989252a76efadc5b72,
-inactive_table_hash=5596cc857b0e887fd0c5d58dc6382513284596b07f09fd37efae2da224bd521d,remove_all=n;
-current_device_capacity=8;
+ 10 56c00cc062ffc24ccd9ac2d67d194af3282b934e ima-buf sha256:e7d12c03b958b4e0e53e7363a06376be88d98a1ac191fdbd3baf5e4b77f329b6
+ dm_device_resume
+ dm_version=4.45.0;
+ name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=4;
+ active_table_hash=sha256:4d73481ecce5eadba8ab084640d85bb9ca899af4d0a122989252a76efadc5b72;current_device_capacity=8;
 
+3. Device remove:
+------------------
+When a device is removed, the device information and a sha256 hash of the
+data from an active and inactive table are measured.
 
-04. Table clear:
+The IMA measurement log has the following format for 'dm_device_remove':
+
+::
+
+ EVENT_NAME := "dm_device_remove"
+ EVENT_DATA := <dm_version_str> ";" <device_active_metadata> ";" <device_inactive_metadata> ";"
+               <active_table_hash> "," <inactive_table_hash> "," <remove_all> ";" <current_device_capacity> ";"
+
+ dm_version_str := As described in the 'Table load' section above.
+ device_active_metadata := Device metadata that reflects the currently loaded active table.
+                           The format is same as 'device_metadata' described in the 'Table load' section above.
+ device_inactive_metadata := Device metadata that reflects the inactive table.
+                             The format is same as 'device_metadata' described in the 'Table load' section above.
+ active_table_hash := Hash of the currently loaded active table.
+                      The format is same as 'active_table_hash' described in the 'Device resume' section above.
+ inactive_table_hash :=  Hash of the inactive table.
+                         The format is same as 'active_table_hash' described in the 'Device resume' section above.
+ remove_all := "remove_all=" <yes_no>
+ yes_no := "y" | "n"
+ current_device_capacity := "current_device_capacity=" <N>
+
+ For instance, if a linear device is removed with the following command,
+  #dmsetup remove l1
+
+ then IMA ASCII measurement log will have the following entry:
+ (converted from ASCII to text for readability)
+
+ 10 790e830a3a7a31590824ac0642b3b31c2d0e8b38 ima-buf sha256:ab9f3c959367a8f5d4403d6ce9c3627dadfa8f9f0e7ec7899299782388de3840
+ dm_device_remove
+ dm_version=4.45.0;
+ device_active_metadata=name=l1,uuid=,major=253,minor=2,minor_count=1,num_targets=2;
+ device_inactive_metadata=name=l1,uuid=,major=253,minor=2,minor_count=1,num_targets=1;
+ active_table_hash=sha256:4a7e62efaebfc86af755831998b7db6f59b60d23c9534fb16a4455907957953a,
+ inactive_table_hash=sha256:9d79c175bc2302d55a183e8f50ad4bafd60f7692fd6249e5fd213e2464384b86,remove_all=n;
+ current_device_capacity=2048;
+
+4. Table clear:
 ----------------
 When an inactive table is cleared from the device, the device information and a sha256 hash of the
 data from an inactive table are measured.
 
-For instance, if a linear device's inactive table is cleared with the following command,
+The IMA measurement log has the following format for 'dm_table_clear':
+
+::
 
-# dmsetup clear linear1
+ EVENT_NAME := "dm_table_clear"
+ EVENT_DATA := <dm_version_str> ";" <device_inactive_metadata> ";" <inactive_table_hash> ";" <current_device_capacity> ";"
 
-Then IMA ASCII measurement log will have an entry with:
-EVENT_NAME := table_clear
-EVENT_DATA := [device_data];inactive_table_hash=(sha256hash([device_data];[inactive_table_row_1];...[inactive_table_row_n]);
-current_device_capacity=<N>;
+ dm_version_str := As described in the 'Table load' section above.
+ device_inactive_metadata := Device metadata that was captured during the load time inactive table being cleared.
+                             The format is same as 'device_metadata' described in the 'Table load' section above.
+ inactive_table_hash := Hash of the inactive table being cleared from the device.
+                        The format is same as 'active_table_hash' described in the 'Device resume' section above.
+ current_device_capacity := "current_device_capacity=" <N>
 
-E.g.
-(converted from ASCII to text for readability)
-10 9c11e284d792875352d51c09f6643c96649484be ima-buf sha256:84b22b364ea4d8264fa33c38635c18ef448fa9077731fa7e5f969b1da2003ea4
-table_clear
-name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=2;
-inactive_table_hash=5596cc857b0e887fd0c5d58dc6382513284596b07f09fd37efae2da224bd521d;current_device_capacity=0;
+ For instance, if a linear device's inactive table is cleared,
+  #dmsetup clear l1
 
+ then IMA ASCII measurement log will have an entry with:
+ (converted from ASCII to text for readability)
 
-05. Device rename:
+ 10 77d347408f557f68f0041acb0072946bb2367fe5 ima-buf sha256:42f9ca22163fdfa548e6229dece2959bc5ce295c681644240035827ada0e1db5
+ dm_table_clear
+ dm_version=4.45.0;
+ name=l1,uuid=,major=253,minor=2,minor_count=1,num_targets=1;
+ inactive_table_hash=sha256:75c0dc347063bf474d28a9907037eba060bfe39d8847fc0646d75e149045d545;current_device_capacity=1024;
+
+5. Device rename:
 ------------------
 When an device's NAME or UUID is changed, the device information and the new NAME and UUID
 are measured.
 
-For instance, if a linear device's name is changed with the following command,
+The IMA measurement log has the following format for 'dm_device_rename':
+
+::
+
+ EVENT_NAME := "dm_device_rename"
+ EVENT_DATA := <dm_version_str> ";" <device_active_metadata> ";" <new_device_name> "," <new_device_uuid> ";" <current_device_capacity> ";"
+
+ dm_version_str := As described in the 'Table load' section above.
+ device_active_metadata := Device metadata that reflects the currently loaded active table.
+                           The format is same as 'device_metadata' described in the 'Table load' section above.
+ new_device_name := "new_name=" <dm-device-name>
+ dm-device-name := Same as <dm-device-name> described in 'Table load' section above
+ new_device_uuid := "new_uuid=" <dm-device-uuid>
+ dm-device-uuid := Same as <dm-device-uuid> described in 'Table load' section above
+ current_device_capacity := "current_device_capacity=" <N>
+
+ E.g 1: if a linear device's name is changed with the following command,
+  #dmsetup rename linear1 --setuuid 1234-5678
 
-#dmsetup rename linear1 linear=2
-Then IMA ASCII measurement log will have an entry with:
-EVENT_NAME := device_rename
-EVENT_DATA := [current_device_data];new_name=<new_name_value>;new_uuid=<new_uuid_value>;current_device_capacity=<N>;
+ then IMA ASCII measurement log will have an entry with:
+ (converted from ASCII to text for readability)
 
-E.g 1:
-#dmsetup rename linear1 --setuuid 1234-5678
+ 10 8b0423209b4c66ac1523f4c9848c9b51ee332f48 ima-buf sha256:6847b7258134189531db593e9230b257c84f04038b5a18fd2e1473860e0569ac
+ dm_device_rename
+ dm_version=4.45.0;
+ name=linear1,uuid=,major=253,minor=2,minor_count=1,num_targets=1;new_name=linear1,new_uuid=1234-5678;
+ current_device_capacity=1024;
 
-IMA Log entry:
-(converted from ASCII to text for readability)
-10 7380ef4d1349fe1ebd74affa54e9fcc960e3cbf5 ima-buf sha256:9759e36a17a967ea43c1bf3455279395a40bd0401105ec5ad8edb9a52054efc7
-device_rename
-name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=1;new_name=linear1,new_uuid=1234-5678;current_device_capacity=2;
+ E.g 2:  if a linear device's name is changed with the following command,
+  # dmsetup rename linear1 linear=2
 
-E.g 2:
-# dmsetup rename linear1 linear=2
-10 092c8266fc36e44f74c59f123ecfe15310f249f4 ima-buf sha256:4cf8b85c81fa6fedaeb602b05019124dbbb0605dce58fcdeea56887a8a3874cd
-device_rename
-name=linear1,uuid=1234-5678,major=253,minor=0,minor_count=1,num_targets=1;new_name=linear\=2,new_uuid=1234-5678;current_device_capacity=2;
+ then IMA ASCII measurement log will have an entry with:
+ (converted from ASCII to text for readability)
 
+ 10 bef70476b99c2bdf7136fae033aa8627da1bf76f ima-buf sha256:8c6f9f53b9ef9dc8f92a2f2cca8910e622543d0f0d37d484870cb16b95111402
+ dm_device_rename
+ dm_version=4.45.0;
+ name=linear1,uuid=1234-5678,major=253,minor=2,minor_count=1,num_targets=1;
+ new_name=linear\=2,new_uuid=1234-5678;
+ current_device_capacity=1024;
 
 Supported targets:
 ==================
-Following targets are supported to measure their data using IMA.
-
-01. cache
-02. crypt
-03. integrity
-04. linear
-05. mirror
-06. multipath
-07. raid
-08. snapshot
-09. striped
-10. verity
 
-01. cache
----------
-<<documenatation in progress>>
+Following targets are supported to measure their data using IMA:
+
+ 1. cache
+ #. crypt
+ #. integrity
+ #. linear
+ #. mirror
+ #. multipath
+ #. raid
+ #. snapshot
+ #. striped
+ #. verity
 
-02. crypt
+1. cache
 ---------
-When a crypt target is loaded, then IMA ASCII measurement log will have an entry
-similar to the following, depicting what crypt attributes are measured in EVENT_DATA.
-
-(converted from ASCII to text for readability)
-10 fe3b80a35b155bd282df778e2625066c05fc068c ima-buf sha256:2d86ce9d6f16a4a97607318aa123ae816e0ceadefeea7903abf7f782f2cb78ad
-table_load
-name=test-crypt,uuid=,major=253,minor=0,minor_count=1,num_targets=1;
-target_index=0,target_begin=0,target_len=1953125,target_name=crypt,target_version=1.23.0,
-allow_discards=y,same_cpu=n,submit_from_crypt_cpus=n,no_read_workqueue=n,no_write_workqueue=n,
-iv_large_sectors=n,cipher_string=aes-xts-plain64,key_size=32,key_parts=1,key_extra_size=0,key_mac_size=0;
-
-03. integrity
+The 'target_attributes' (described as part of EVENT_DATA in 'Table load'
+section above) has the following data format for 'cache' target.
+
+::
+
+ target_attributes := <target_name> "," <target_version> "," <metadata_mode> "," <cache_metadata_device> ","
+                      <cache_device> "," <cache_origin_device> "," <writethrough> "," <writeback> ","
+                      <passthrough> "," <no_discard_passdown> ";"
+
+ target_name := "target_name=cache"
+ target_version := "target_version=" <N> "." <N> "." <N>
+ metadata_mode := "metadata_mode=" <cache_metadata_mode>
+ cache_metadata_mode := "fail" | "ro" | "rw"
+ cache_device := "cache_device=" <cache_device_name_string>
+ cache_origin_device := "cache_origin_device=" <cache_origin_device_string>
+ writethrough := "writethrough=" <yes_no>
+ writeback := "writeback=" <yes_no>
+ passthrough := "passthrough=" <yes_no>
+ no_discard_passdown := "no_discard_passdown=" <yes_no>
+ yes_no := "y" | "n"
+
+ E.g.
+ When a 'cache' target is loaded, then IMA ASCII measurement log will have an entry
+ similar to the following, depicting what 'cache' attributes are measured in EVENT_DATA
+ for 'dm_table_load' event.
+ (converted from ASCII to text for readability)
+
+ dm_version=4.45.0;name=cache1,uuid=cache_uuid,major=253,minor=2,minor_count=1,num_targets=1;
+ target_index=0,target_begin=0,target_len=28672,target_name=cache,target_version=2.2.0,metadata_mode=rw,
+ cache_metadata_device=253:4,cache_device=253:3,cache_origin_device=253:5,writethrough=y,writeback=n,
+ passthrough=n,metadata2=y,no_discard_passdown=n;
+
+
+2. crypt
+---------
+The 'target_attributes' (described as part of EVENT_DATA in 'Table load'
+section above) has the following data format for 'crypt' target.
+
+::
+
+ target_attributes := <target_name> "," <target_version> "," <allow_discards> "," <same_cpu_crypt> ","
+                      <submit_from_crypt_cpus> "," <no_read_workqueue> "," <no_write_workqueue> ","
+                      <iv_large_sectors> "," <iv_large_sectors> "," [<integrity_tag_size> ","] [<cipher_auth> ","]
+                      [<sector_size> ","] [<cipher_string> ","] <key_size> "," <key_parts> ","
+                      <key_extra_size> "," <key_mac_size> ";"
+
+ target_name := "target_name=crypt"
+ target_version := "target_version=" <N> "." <N> "." <N>
+ allow_discards := "allow_discards=" <yes_no>
+ same_cpu_crypt := "same_cpu_crypt=" <yes_no>
+ submit_from_crypt_cpus := "submit_from_crypt_cpus=" <yes_no>
+ no_read_workqueue := "no_read_workqueue=" <yes_no>
+ no_write_workqueue := "no_write_workqueue=" <yes_no>
+ iv_large_sectors := "iv_large_sectors=" <yes_no>
+ integrity_tag_size := "integrity_tag_size=" <N>
+ cipher_auth := "cipher_auth=" <string>
+ sector_size := "sector_size="  <N>
+ cipher_string := "cipher_string="
+ key_size := "key_size="  <N>
+ key_parts := "key_parts="  <N>
+ key_extra_size := "key_extra_size="  <N>
+ key_mac_size := "key_mac_size="  <N>
+ yes_no := "y" | "n"
+
+ E.g.
+ When a 'crypt' target is loaded, then IMA ASCII measurement log will have an entry
+ similar to the following, depicting what 'crypt' attributes are measured in EVENT_DATA
+ for 'dm_table_load' event.
+ (converted from ASCII to text for readability)
+
+ dm_version=4.45.0;
+ name=crypt1,uuid=crypt_uuid1,major=253,minor=0,minor_count=1,num_targets=1;
+ target_index=0,target_begin=0,target_len=1953125,target_name=crypt,target_version=1.23.0,
+ allow_discards=y,same_cpu=n,submit_from_crypt_cpus=n,no_read_workqueue=n,no_write_workqueue=n,
+ iv_large_sectors=n,cipher_string=aes-xts-plain64,key_size=32,key_parts=1,key_extra_size=0,key_mac_size=0;
+
+3. integrity
 -------------
-<<documenatation in progress>>
+The 'target_attributes' (described as part of EVENT_DATA in 'Table load'
+section above) has the following data format for 'integrity' target.
+
+::
+
+ target_attributes := <target_name> "," <target_version> "," <dev_name> "," <start>
+                      <tag_size> "," <mode> "," [<meta_device> ","] [<block_size> ","] <recalculate> ","
+                      <allow_discards> "," <fix_padding> "," <fix_hmac> "," <legacy_recalculate> ","
+                      <journal_sectors> "," <interleave_sectors> "," <buffer_sectors> ";"
+
+ target_name := "target_name=integrity"
+ target_version := "target_version=" <N> "." <N> "." <N>
+ dev_name := "dev_name=" <device_name_str>
+ start := "start=" <N>
+ tag_size := "tag_size=" <N>
+ mode := "mode=" <integrity_mode_str>
+ integrity_mode_str := "J" | "B" | "D" | "R"
+ meta_device := "meta_device=" <meta_device_str>
+ block_size := "block_size=" <N>
+ recalculate := "recalculate=" <yes_no>
+ allow_discards := "allow_discards=" <yes_no>
+ fix_padding := "fix_padding=" <yes_no>
+ fix_hmac := "fix_hmac=" <yes_no>
+ legacy_recalculate := "legacy_recalculate=" <yes_no>
+ journal_sectors := "journal_sectors=" <N>
+ interleave_sectors := "interleave_sectors=" <N>
+ buffer_sectors := "buffer_sectors=" <N>
+ yes_no := "y" | "n"
+
+ E.g.
+ When a 'integrity' target is loaded, then IMA ASCII measurement log will have an entry
+ similar to the following, depicting what 'integrity' attributes are measured in EVENT_DATA
+ for 'dm_table_load' event.
+ (converted from ASCII to text for readability)
+
+ dm_version=4.45.0;
+ name=integrity1,uuid=,major=253,minor=1,minor_count=1,num_targets=1;
+ target_index=0,target_begin=0,target_len=7856,target_name=integrity,target_version=1.10.0,
+ dev_name=253:0,start=0,tag_size=32,mode=J,recalculate=n,allow_discards=n,fix_padding=n,
+ fix_hmac=n,legacy_recalculate=n,journal_sectors=88,interleave_sectors=32768,buffer_sectors=128;
+
+
+4. linear
+----------
+The 'target_attributes' (described as part of EVENT_DATA in 'Table load'
+section above) has the following data format for 'linear' target.
 
+::
 
-04. linear
-----------
-When a linear target is loaded, then IMA ASCII measurement log will have an entry
-similar to the following, depicting what linear attributes are measured in EVENT_DATA.
-
-(converted from ASCII to text for readability)
-10 a8c5ff755561c7a28146389d1514c318592af49a ima-buf sha256:4d73481ecce5eadba8ab084640d85bb9ca899af4d0a122989252a76efadc5b72
-table_load
-name=linear1,uuid=,major=253,minor=0,minor_count=1,num_targets=4;
-target_index=0,target_begin=0,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
-target_index=1,target_begin=2,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
-target_index=2,target_begin=4,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
-target_index=3,target_begin=6,target_len=2,target_name=linear,target_version=1.4.0,device_name=7:0,start=512;
-
-05. mirror
-----------
-When a mirror target is loaded, then IMA ASCII measurement log will have an entry
-similar to the following, depicting what mirror attributes are measured in EVENT_DATA.
-
-(converted from ASCII to text for readability)
-10 90ff9113a00c367df823595dc347425ce3bfc50a ima-buf sha256:8da0678ed3bf616533573d9e61e5342f2bd16cb0b3145a08262641a743806c2e
-table_load
-name=test-mirror,uuid=,major=253,minor=4,minor_count=1,num_targets=1;
-target_index=0,target_begin=0,target_len=1953125,target_name=mirror,target_version=1.14.0,
-nr_mirrors=2,mirror_device_0=253:2,mirror_device_0_status=A,mirror_device_1=253:3,mirror_device_1_status=A,
-handle_errors=y,keep_log=n,log_type_status=;
-
-06. multipath
--------------
-<<documenatation in progress>>
+ target_attributes := <target_name> "," <target_version> "," <device_name> <,> <start> ";"
 
-07. raid
---------
-When a raid target is loaded, then IMA ASCII measurement log will have an entry
-similar to the following, depicting what raid attributes are measured in EVENT_DATA.
+ target_name := "target_name=linear"
+ target_version := "target_version=" <N> "." <N> "." <N>
+ device_name := "device_name=" <linear_device_name_str>
+ start := "start=" <N>
 
-(converted from ASCII to text for readability)
-10 76cb30d0cd0fe099966f20f5c82e3a2ac29b21a0 ima-buf sha256:52250f20b27376fcfb348bdfa1e1cf5acfd6646e0f3ad1a72952cffd9f818753
-table_load
-name=test-raid1,uuid=,major=253,minor=2,minor_count=1,num_targets=1;
-target_index=0,target_begin=0,target_len=1953125,target_name=raid,target_version=1.15.1,
-raid_type=raid1,raid_disks=2,raid_state=idle,raid_device_0_status=A,raid_device_1_status=A;
+ E.g.
+ When a 'linear' target is loaded, then IMA ASCII measurement log will have an entry
+ similar to the following, depicting what 'linear' attributes are measured in EVENT_DATA
+ for 'dm_table_load' event.
+ (converted from ASCII to text for readability)
 
-08. snapshot
-------------
-<<documenatation in progress>>
+ dm_version=4.45.0;
+ name=linear1,uuid=linear_uuid1,major=253,minor=2,minor_count=1,num_targets=1;
+ target_index=0,target_begin=0,target_len=28672,target_name=linear,target_version=1.4.0,
+ device_name=253:1,start=2048;
 
-09. striped
+5. mirror
+----------
+The 'target_attributes' (described as part of EVENT_DATA in 'Table load'
+section above) has the following data format for 'mirror' target.
+
+::
+
+ target_attributes := <target_name> "," <target_version> "," <nr_mirrors> ","
+                      <mirror_device_data> "," <handle_errors> "," <keep_log> "," <log_type_status> ";"
+
+ target_name := "target_name=mirror"
+ target_version := "target_version=" <N> "." <N> "." <N>
+ nr_mirrors := "nr_mirrors=" <NR>
+ mirror_device_data := <mirror_device_row> | <mirror_device_data><mirror_device_row>
+                       mirror_device_row is repeated <NR> times - for <NR> described in <nr_mirrors>.
+ mirror_device_row := <mirror_device_name> "," <mirror_device_status>
+ mirror_device_name := "mirror_device_" <X> "=" <mirror_device_name_str>
+                       where <X> ranges from 0 to (<NR> -1) - for <NR> described in <nr_mirrors>.
+ mirror_device_status := "mirror_device_" <X> "_status=" <mirror_device_status_char>
+                         where <X> ranges from 0 to (<NR> -1) - for <NR> described in <nr_mirrors>.
+ mirror_device_status_char := "A" | "F" | "D" | "S" | "R" | "U"
+ handle_errors := "handle_errors=" <yes_no>
+ keep_log := "keep_log=" <yes_no>
+ log_type_status := "log_type_status=" <log_type_status_str>
+ yes_no := "y" | "n"
+
+ E.g.
+ When a 'mirror' target is loaded, then IMA ASCII measurement log will have an entry
+ similar to the following, depicting what 'mirror' attributes are measured in EVENT_DATA
+ for 'dm_table_load' event.
+ (converted from ASCII to text for readability)
+
+ dm_version=4.45.0;
+ name=mirror1,uuid=mirror_uuid1,major=253,minor=6,minor_count=1,num_targets=1;
+ target_index=0,target_begin=0,target_len=2048,target_name=mirror,target_version=1.14.0,nr_mirrors=2,
+    mirror_device_0=253:4,mirror_device_0_status=A,
+    mirror_device_1=253:5,mirror_device_1_status=A,
+ handle_errors=y,keep_log=n,log_type_status=;
+
+6. multipath
+-------------
+The 'target_attributes' (described as part of EVENT_DATA in 'Table load'
+section above) has the following data format for 'multipath' target.
+
+::
+
+ target_attributes := <target_name> "," <target_version> "," <nr_priority_groups>
+                      ["," <pg_state> "," <priority_groups> "," <priority_group_paths>] ";"
+
+ target_name := "target_name=multipath"
+ target_version := "target_version=" <N> "." <N> "." <N>
+ nr_priority_groups := "nr_priority_groups=" <NPG>
+ priority_groups := <priority_groups_row>|<priority_groups_row><priority_groups>
+ priority_groups_row := "pg_state_" <X> "=" <pg_state_str> "," "nr_pgpaths_" <X>  "=" <NPGP> ","
+                        "path_selector_name_" <X> "=" <string> "," <priority_group_paths>
+                        where <X> ranges from 0 to (<NPG> -1) - for <NPG> described in <nr_priority_groups>.
+ pg_state_str := "E" | "A" | "D"
+ <priority_group_paths> := <priority_group_paths_row> | <priority_group_paths_row><priority_group_paths>
+ priority_group_paths_row := "path_name_" <X> "_" <Y> "=" <string> "," "is_active_" <X> "_" <Y> "=" <is_active_str>
+                             "fail_count_" <X> "_" <Y> "=" <N> "," "path_selector_status_" <X> "_" <Y> "=" <path_selector_status_str>
+                             where <X> ranges from 0 to (<NPG> -1) - for <NPG> described in <nr_priority_groups>,
+                             and <Y> ranges from 0 to (<NPGP> -1) - for <NPGP> described in <priority_groups_row>.
+ is_active_str := "A" | "F"
+
+ E.g.
+ When a 'multipath' target is loaded, then IMA ASCII measurement log will have an entry
+ similar to the following, depicting what 'multipath' attributes are measured in EVENT_DATA
+ for 'dm_table_load' event.
+ (converted from ASCII to text for readability)
+
+ dm_version=4.45.0;
+ name=mp,uuid=,major=253,minor=0,minor_count=1,num_targets=1;
+ target_index=0,target_begin=0,target_len=2097152,target_name=multipath,target_version=1.14.0,nr_priority_groups=2,
+    pg_state_0=E,nr_pgpaths_0=2,path_selector_name_0=queue-length,
+        path_name_0_0=8:16,is_active_0_0=A,fail_count_0_0=0,path_selector_status_0_0=,
+        path_name_0_1=8:32,is_active_0_1=A,fail_count_0_1=0,path_selector_status_0_1=,
+    pg_state_1=E,nr_pgpaths_1=2,path_selector_name_1=queue-length,
+        path_name_1_0=8:48,is_active_1_0=A,fail_count_1_0=0,path_selector_status_1_0=,
+        path_name_1_1=8:64,is_active_1_1=A,fail_count_1_1=0,path_selector_status_1_1=;
+
+7. raid
+--------
+The 'target_attributes' (described as part of EVENT_DATA in 'Table load'
+section above) has the following data format for 'raid' target.
+
+::
+
+ target_attributes := <target_name> "," <target_version> "," <raid_type> "," <raid_disks> "," <raid_state>
+                      <raid_device_status> ["," journal_dev_mode] ";"
+
+ target_name := "target_name=raid"
+ target_version := "target_version=" <N> "." <N> "." <N>
+ raid_type := "raid_type=" <raid_type_str>
+ raid_disks := "raid_disks=" <NRD>
+ raid_state := "raid_state=" <raid_state_str>
+ raid_state_str := "frozen" | "reshape" |"resync" | "check" | "repair" | "recover" | "idle" |"undef"
+ raid_device_status := <raid_device_status_row> | <raid_device_status_row><raid_device_status>
+                       <raid_device_status_row> is repeated <NRD> times - for <NRD> described in <raid_disks>.
+ raid_device_status_row := "raid_device_" <X> "_status=" <raid_device_status_str>
+                           where <X> ranges from 0 to (<NRD> -1) - for <NRD> described in <raid_disks>.
+ raid_device_status_str := "A" | "D" | "a" | "-"
+ journal_dev_mode := "journal_dev_mode=" <journal_dev_mode_str>
+ journal_dev_mode_str := "writethrough" | "writeback" | "invalid"
+
+ E.g.
+ When a 'raid' target is loaded, then IMA ASCII measurement log will have an entry
+ similar to the following, depicting what 'raid' attributes are measured in EVENT_DATA
+ for 'dm_table_load' event.
+ (converted from ASCII to text for readability)
+
+ dm_version=4.45.0;
+ name=raid_LV1,uuid=uuid_raid_LV1,major=253,minor=12,minor_count=1,num_targets=1;
+ target_index=0,target_begin=0,target_len=2048,target_name=raid,target_version=1.15.1,
+ raid_type=raid10,raid_disks=4,raid_state=idle,
+    raid_device_0_status=A,
+    raid_device_1_status=A,
+    raid_device_2_status=A,
+    raid_device_3_status=A;
+
+
+8. snapshot
+------------
+The 'target_attributes' (described as part of EVENT_DATA in 'Table load'
+section above) has the following data format for 'snapshot' target.
+
+::
+
+ target_attributes := <target_name> "," <target_version> "," <snap_origin_name> ","
+                      <snap_cow_name> "," <snap_valid> "," <snap_merge_failed> "," <snapshot_overflowed> ";"
+
+ target_name := "target_name=snapshot"
+ target_version := "target_version=" <N> "." <N> "." <N>
+ snap_origin_name := "snap_origin_name=" <string>
+ snap_cow_name := "snap_cow_name=" <string>
+ snap_valid := "snap_valid=" <yes_no>
+ snap_merge_failed := "snap_merge_failed=" <yes_no>
+ snapshot_overflowed := "snapshot_overflowed=" <yes_no>
+ yes_no := "y" | "n"
+
+ E.g.
+ When a 'snapshot' target is loaded, then IMA ASCII measurement log will have an entry
+ similar to the following, depicting what 'snapshot' attributes are measured in EVENT_DATA
+ for 'dm_table_load' event.
+ (converted from ASCII to text for readability)
+
+ dm_version=4.45.0;
+ name=snap1,uuid=snap_uuid1,major=253,minor=13,minor_count=1,num_targets=1;
+ target_index=0,target_begin=0,target_len=4096,target_name=snapshot,target_version=1.16.0,
+ snap_origin_name=253:11,snap_cow_name=253:12,snap_valid=y,snap_merge_failed=n,snapshot_overflowed=n;
+
+9. striped
 -----------
-When a linear target is loaded, then IMA ASCII measurement log will have an entry
-similar to the following, depicting what linear attributes are measured in EVENT_DATA.
-
-(converted from ASCII to text for readability)
-10 7bd94fa8f799169b9f12d97b9dbdce4dc5509233 ima-buf sha256:0d148eda69887f7833f1a6042767b54359cd23b64fa941b9e1856879eee1f778
-table_load
-name=test-raid0,uuid=,major=253,minor=8,minor_count=1,num_targets=1;
-target_index=0,target_begin=0,target_len=7812096,target_name=striped,target_version=1.6.0,stripes=4,chunk_size=128,
-stripe_0_device_name=253:1,stripe_0_physical_start=0,stripe_0_status=A,
-stripe_1_device_name=253:3,stripe_1_physical_start=0,stripe_1_status=A,
-stripe_2_device_name=253:5,stripe_2_physical_start=0,stripe_2_status=A,
-stripe_3_device_name=253:7,stripe_3_physical_start=0,stripe_3_status=A;
+The 'target_attributes' (described as part of EVENT_DATA in 'Table load'
+section above) has the following data format for 'striped' target.
+
+::
+
+ target_attributes := <target_name> "," <target_version> "," <stripes> "," <chunk_size> ","
+                      <stripe_data> ";"
+
+ target_name := "target_name=striped"
+ target_version := "target_version=" <N> "." <N> "." <N>
+ stripes := "stripes=" <NS>
+ chunk_size := "chunk_size=" <N>
+ stripe_data := <stripe_data_row>|<stripe_data><stripe_data_row>
+ stripe_data_row := <stripe_device_name> "," <stripe_physical_start> "," <stripe_status>
+ stripe_device_name := "stripe_" <X> "_device_name=" <stripe_device_name_str>
+                       where <X> ranges from 0 to (<NS> -1) - for <NS> described in <stripes>.
+ stripe_physical_start := "stripe_" <X> "_physical_start=" <N>
+                           where <X> ranges from 0 to (<NS> -1) - for <NS> described in <stripes>.
+ stripe_status := "stripe_" <X> "_status=" <stripe_status_str>
+                  where <X> ranges from 0 to (<NS> -1) - for <NS> described in <stripes>.
+ stripe_status_str := "D" | "A"
+
+ E.g.
+ When a 'striped' target is loaded, then IMA ASCII measurement log will have an entry
+ similar to the following, depicting what 'striped' attributes are measured in EVENT_DATA
+ for 'dm_table_load' event.
+ (converted from ASCII to text for readability)
+
+ dm_version=4.45.0;
+ name=striped1,uuid=striped_uuid1,major=253,minor=5,minor_count=1,num_targets=1;
+ target_index=0,target_begin=0,target_len=640,target_name=striped,target_version=1.6.0,stripes=2,chunk_size=64,
+    stripe_0_device_name=253:0,stripe_0_physical_start=2048,stripe_0_status=A,
+    stripe_1_device_name=253:3,stripe_1_physical_start=2048,stripe_1_status=A;
 
 10. verity
 ----------
-When a verity target is loaded, then IMA ASCII measurement log will have an entry
-similar to the following, depicting what verity attributes are measured in EVENT_DATA.
-
-(converted from ASCII to text for readability)
-10 fced5f575b140fc0efac302c88a635174cd663da ima-buf sha256:021370c1cc93929460b06922c606334fb1d7ea5ecf04f2384f3157a446894283
-table_load
-name=test-verity,uuid=,major=253,minor=2,minor_count=1,num_targets=1;
-target_index=0,target_begin=0,target_len=1953120,target_name=verity,target_version=1.8.0,hash_failed=V,
-verity_version=1,data_device_name=253:1,hash_device_name=253:0,verity_algorithm=sha256,
-root_digest=29cb87e60ce7b12b443ba6008266f3e41e93e403d7f298f8e3f316b29ff89c5e,
-salt=e48da609055204e89ae53b655ca2216dd983cf3cb829f34f63a297d106d53e2d,
-ignore_zero_blocks=n,check_at_most_once=n;
+The 'target_attributes' (described as part of EVENT_DATA in 'Table load'
+section above) has the following data format for 'verity' target.
+
+::
+
+ target_attributes := <target_name> "," <target_version> "," <hash_failed> "," <verity_version> ","
+                      <data_device_name> "," <hash_device_name> "," <verity_algorithm> "," <root_digest> ","
+                      <salt> "," <ignore_zero_blocks> "," <check_at_most_once> ["," <root_hash_sig_key_desc>]
+                      ["," <verity_mode>] ";"
+
+ target_name := "target_name=verity"
+ target_version := "target_version=" <N> "." <N> "." <N>
+ hash_failed := "hash_failed=" <hash_failed_str>
+ hash_failed_str := "C" | "V"
+ verity_version := "verity_version=" <verity_version_str>
+ data_device_name := "data_device_name=" <data_device_name_str>
+ hash_device_name := "hash_device_name=" <hash_device_name_str>
+ verity_algorithm := "verity_algorithm=" <verity_algorithm_str>
+ root_digest := "root_digest=" <root_digest_str>
+ salt := "salt=" <salt_str>
+ salt_str := "-" <verity_salt_str>
+ ignore_zero_blocks := "ignore_zero_blocks=" <yes_no>
+ check_at_most_once := "check_at_most_once=" <yes_no>
+ root_hash_sig_key_desc := "root_hash_sig_key_desc="
+ verity_mode := "verity_mode=" <verity_mode_str>
+ verity_mode_str := "ignore_corruption" | "restart_on_corruption" | "panic_on_corruption" | "invalid"
+ yes_no := "y" | "n"
+
+ E.g.
+ When a 'verity' target is loaded, then IMA ASCII measurement log will have an entry
+ similar to the following, depicting what 'verity' attributes are measured in EVENT_DATA
+ for 'dm_table_load' event.
+ (converted from ASCII to text for readability)
+
+ dm_version=4.45.0;
+ name=test-verity,uuid=,major=253,minor=2,minor_count=1,num_targets=1;
+ target_index=0,target_begin=0,target_len=1953120,target_name=verity,target_version=1.8.0,hash_failed=V,
+ verity_version=1,data_device_name=253:1,hash_device_name=253:0,verity_algorithm=sha256,
+ root_digest=29cb87e60ce7b12b443ba6008266f3e41e93e403d7f298f8e3f316b29ff89c5e,
+ salt=e48da609055204e89ae53b655ca2216dd983cf3cb829f34f63a297d106d53e2d,
+ ignore_zero_blocks=n,check_at_most_once=n;
-- 
cgit v1.2.3


From d3703ef331297b6daa97f5228cbe2a657d0cfd21 Mon Sep 17 00:00:00 2001
From: Changbin Du <changbin.du@gmail.com>
Date: Sat, 14 Aug 2021 09:09:09 +0800
Subject: dm crypt: use in_hardirq() instead of deprecated in_irq()

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/md/dm-crypt.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 9d15872dbe40..916b7da16de2 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -2223,11 +2223,11 @@ static void kcryptd_queue_crypt(struct dm_crypt_io *io)
 	if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) ||
 	    (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) {
 		/*
-		 * in_irq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context.
+		 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context.
 		 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but
 		 * it is being executed with irqs disabled.
 		 */
-		if (in_irq() || irqs_disabled()) {
+		if (in_hardirq() || irqs_disabled()) {
 			tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work);
 			tasklet_schedule(&io->tasklet);
 			return;
-- 
cgit v1.2.3