diff options
Diffstat (limited to 'block/partitions')
-rw-r--r-- | block/partitions/amiga.c | 102 | ||||
-rw-r--r-- | block/partitions/core.c | 50 |
2 files changed, 114 insertions, 38 deletions
diff --git a/block/partitions/amiga.c b/block/partitions/amiga.c index 5c8624e26a54..ed222b9c901b 100644 --- a/block/partitions/amiga.c +++ b/block/partitions/amiga.c @@ -11,10 +11,18 @@ #define pr_fmt(fmt) fmt #include <linux/types.h> +#include <linux/mm_types.h> +#include <linux/overflow.h> #include <linux/affs_hardblocks.h> #include "check.h" +/* magic offsets in partition DosEnvVec */ +#define NR_HD 3 +#define NR_SECT 5 +#define LO_CYL 9 +#define HI_CYL 10 + static __inline__ u32 checksum_block(__be32 *m, int size) { @@ -31,8 +39,12 @@ int amiga_partition(struct parsed_partitions *state) unsigned char *data; struct RigidDiskBlock *rdb; struct PartitionBlock *pb; - int start_sect, nr_sects, blk, part, res = 0; - int blksize = 1; /* Multiplier for disk block size */ + u64 start_sect, nr_sects; + sector_t blk, end_sect; + u32 cylblk; /* rdb_CylBlocks = nr_heads*sect_per_track */ + u32 nr_hd, nr_sect, lo_cyl, hi_cyl; + int part, res = 0; + unsigned int blksize = 1; /* Multiplier for disk block size */ int slot = 1; for (blk = 0; ; blk++, put_dev_sector(sect)) { @@ -40,7 +52,7 @@ int amiga_partition(struct parsed_partitions *state) goto rdb_done; data = read_part_sector(state, blk, §); if (!data) { - pr_err("Dev %s: unable to read RDB block %d\n", + pr_err("Dev %s: unable to read RDB block %llu\n", state->disk->disk_name, blk); res = -1; goto rdb_done; @@ -57,12 +69,12 @@ int amiga_partition(struct parsed_partitions *state) *(__be32 *)(data+0xdc) = 0; if (checksum_block((__be32 *)data, be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F)==0) { - pr_err("Trashed word at 0xd0 in block %d ignored in checksum calculation\n", + pr_err("Trashed word at 0xd0 in block %llu ignored in checksum calculation\n", blk); break; } - pr_err("Dev %s: RDB in block %d has bad checksum\n", + pr_err("Dev %s: RDB in block %llu has bad checksum\n", state->disk->disk_name, blk); } @@ -79,10 +91,15 @@ int amiga_partition(struct parsed_partitions *state) blk = be32_to_cpu(rdb->rdb_PartitionList); put_dev_sector(sect); for (part = 1; blk>0 && part<=16; part++, put_dev_sector(sect)) { - blk *= blksize; /* Read in terms partition table understands */ + /* Read in terms partition table understands */ + if (check_mul_overflow(blk, (sector_t) blksize, &blk)) { + pr_err("Dev %s: overflow calculating partition block %llu! Skipping partitions %u and beyond\n", + state->disk->disk_name, blk, part); + break; + } data = read_part_sector(state, blk, §); if (!data) { - pr_err("Dev %s: unable to read partition block %d\n", + pr_err("Dev %s: unable to read partition block %llu\n", state->disk->disk_name, blk); res = -1; goto rdb_done; @@ -94,19 +111,70 @@ int amiga_partition(struct parsed_partitions *state) if (checksum_block((__be32 *)pb, be32_to_cpu(pb->pb_SummedLongs) & 0x7F) != 0 ) continue; - /* Tell Kernel about it */ + /* RDB gives us more than enough rope to hang ourselves with, + * many times over (2^128 bytes if all fields max out). + * Some careful checks are in order, so check for potential + * overflows. + * We are multiplying four 32 bit numbers to one sector_t! + */ + + nr_hd = be32_to_cpu(pb->pb_Environment[NR_HD]); + nr_sect = be32_to_cpu(pb->pb_Environment[NR_SECT]); + + /* CylBlocks is total number of blocks per cylinder */ + if (check_mul_overflow(nr_hd, nr_sect, &cylblk)) { + pr_err("Dev %s: heads*sects %u overflows u32, skipping partition!\n", + state->disk->disk_name, cylblk); + continue; + } + + /* check for consistency with RDB defined CylBlocks */ + if (cylblk > be32_to_cpu(rdb->rdb_CylBlocks)) { + pr_warn("Dev %s: cylblk %u > rdb_CylBlocks %u!\n", + state->disk->disk_name, cylblk, + be32_to_cpu(rdb->rdb_CylBlocks)); + } + + /* RDB allows for variable logical block size - + * normalize to 512 byte blocks and check result. + */ + + if (check_mul_overflow(cylblk, blksize, &cylblk)) { + pr_err("Dev %s: partition %u bytes per cyl. overflows u32, skipping partition!\n", + state->disk->disk_name, part); + continue; + } + + /* Calculate partition start and end. Limit of 32 bit on cylblk + * guarantees no overflow occurs if LBD support is enabled. + */ + + lo_cyl = be32_to_cpu(pb->pb_Environment[LO_CYL]); + start_sect = ((u64) lo_cyl * cylblk); + + hi_cyl = be32_to_cpu(pb->pb_Environment[HI_CYL]); + nr_sects = (((u64) hi_cyl - lo_cyl + 1) * cylblk); - nr_sects = (be32_to_cpu(pb->pb_Environment[10]) + 1 - - be32_to_cpu(pb->pb_Environment[9])) * - be32_to_cpu(pb->pb_Environment[3]) * - be32_to_cpu(pb->pb_Environment[5]) * - blksize; if (!nr_sects) continue; - start_sect = be32_to_cpu(pb->pb_Environment[9]) * - be32_to_cpu(pb->pb_Environment[3]) * - be32_to_cpu(pb->pb_Environment[5]) * - blksize; + + /* Warn user if partition end overflows u32 (AmigaDOS limit) */ + + if ((start_sect + nr_sects) > UINT_MAX) { + pr_warn("Dev %s: partition %u (%llu-%llu) needs 64 bit device support!\n", + state->disk->disk_name, part, + start_sect, start_sect + nr_sects); + } + + if (check_add_overflow(start_sect, nr_sects, &end_sect)) { + pr_err("Dev %s: partition %u (%llu-%llu) needs LBD device support, skipping partition!\n", + state->disk->disk_name, part, + start_sect, end_sect); + continue; + } + + /* Tell Kernel about it */ + put_partition(state,slot++,start_sect,nr_sects); { /* Be even more informative to aid mounting */ diff --git a/block/partitions/core.c b/block/partitions/core.c index 49e0496ff23c..13a7341299a9 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -12,7 +12,7 @@ #include <linux/raid/detect.h> #include "check.h" -static int (*check_part[])(struct parsed_partitions *) = { +static int (*const check_part[])(struct parsed_partitions *) = { /* * Probe partition formats with tables at disk address 0 * that also have an ADFS boot block at 0xdc0. @@ -228,7 +228,7 @@ static struct attribute *part_attrs[] = { NULL }; -static struct attribute_group part_attr_group = { +static const struct attribute_group part_attr_group = { .attrs = part_attrs, }; @@ -256,31 +256,36 @@ static int part_uevent(const struct device *dev, struct kobj_uevent_env *env) return 0; } -struct device_type part_type = { +const struct device_type part_type = { .name = "partition", .groups = part_attr_groups, .release = part_release, .uevent = part_uevent, }; -static void delete_partition(struct block_device *part) +void drop_partition(struct block_device *part) { lockdep_assert_held(&part->bd_disk->open_mutex); - fsync_bdev(part); - __invalidate_device(part, true); - xa_erase(&part->bd_disk->part_tbl, part->bd_partno); kobject_put(part->bd_holder_dir); + device_del(&part->bd_device); + put_device(&part->bd_device); +} +static void delete_partition(struct block_device *part) +{ /* * Remove the block device from the inode hash, so that it cannot be * looked up any more even when openers still hold references. */ remove_inode_hash(part->bd_inode); - put_device(&part->bd_device); + fsync_bdev(part); + __invalidate_device(part, true); + + drop_partition(part); } static ssize_t whole_disk_show(struct device *dev, @@ -288,7 +293,7 @@ static ssize_t whole_disk_show(struct device *dev, { return 0; } -static DEVICE_ATTR(whole_disk, 0444, whole_disk_show, NULL); +static const DEVICE_ATTR(whole_disk, 0444, whole_disk_show, NULL); /* * Must be called either with open_mutex held, before a disk can be opened or @@ -436,10 +441,21 @@ static bool partition_overlaps(struct gendisk *disk, sector_t start, int bdev_add_partition(struct gendisk *disk, int partno, sector_t start, sector_t length) { + sector_t capacity = get_capacity(disk), end; struct block_device *part; int ret; mutex_lock(&disk->open_mutex); + if (check_add_overflow(start, length, &end)) { + ret = -EINVAL; + goto out; + } + + if (start >= capacity || end > capacity) { + ret = -EINVAL; + goto out; + } + if (!disk_live(disk)) { ret = -ENXIO; goto out; @@ -519,17 +535,6 @@ static bool disk_unlock_native_capacity(struct gendisk *disk) return true; } -void blk_drop_partitions(struct gendisk *disk) -{ - struct block_device *part; - unsigned long idx; - - lockdep_assert_held(&disk->open_mutex); - - xa_for_each_start(&disk->part_tbl, idx, part, 1) - delete_partition(part); -} - static bool blk_add_partition(struct gendisk *disk, struct parsed_partitions *state, int p) { @@ -646,6 +651,8 @@ out_free_state: int bdev_disk_changed(struct gendisk *disk, bool invalidate) { + struct block_device *part; + unsigned long idx; int ret = 0; lockdep_assert_held(&disk->open_mutex); @@ -658,8 +665,9 @@ rescan: return -EBUSY; sync_blockdev(disk->part0); invalidate_bdev(disk->part0); - blk_drop_partitions(disk); + xa_for_each_start(&disk->part_tbl, idx, part, 1) + delete_partition(part); clear_bit(GD_NEED_PART_SCAN, &disk->state); /* |