diff options
| author | Matthew Mirvish <matthew@mm12.xyz> | 2024-05-09 04:11:17 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2024-05-09 04:15:01 +0300 |
| commit | 3a861560ccb35f2a4f0a4b8207fa7c2a35fc7f31 (patch) | |
| tree | abaed8a75822748de1e372b1ae2a828a8545468d /drivers/md/bcache/super.c | |
| parent | 2abd9a197d828ed5c2cbe922368eb28d02861a28 (diff) | |
| download | linux-3a861560ccb35f2a4f0a4b8207fa7c2a35fc7f31.tar.xz | |
bcache: fix variable length array abuse in btree_iter
btree_iter is used in two ways: either allocated on the stack with a
fixed size MAX_BSETS, or from a mempool with a dynamic size based on the
specific cache set. Previously, the struct had a fixed-length array of
size MAX_BSETS which was indexed out-of-bounds for the dynamically-sized
iterators, which causes UBSAN to complain.
This patch uses the same approach as in bcachefs's sort_iter and splits
the iterator into a btree_iter with a flexible array member and a
btree_iter_stack which embeds a btree_iter as well as a fixed-length
data array.
Cc: stable@vger.kernel.org
Closes: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2039368
Signed-off-by: Matthew Mirvish <matthew@mm12.xyz>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20240509011117.2697-3-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/md/bcache/super.c')
| -rw-r--r-- | drivers/md/bcache/super.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 38e41039edb8..cba09660148a 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1914,8 +1914,9 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb) INIT_LIST_HEAD(&c->btree_cache_freed); INIT_LIST_HEAD(&c->data_buckets); - iter_size = ((meta_bucket_pages(sb) * PAGE_SECTORS) / sb->block_size + 1) * - sizeof(struct btree_iter_set); + iter_size = sizeof(struct btree_iter) + + ((meta_bucket_pages(sb) * PAGE_SECTORS) / sb->block_size) * + sizeof(struct btree_iter_set); c->devices = kcalloc(c->nr_uuids, sizeof(void *), GFP_KERNEL); if (!c->devices) |