diff options
| author | Mikulas Patocka | 2022-06-16 13:28:57 -0400 |
|---|---|---|
| committer | Mike Snitzer | 2022-06-16 19:39:29 -0400 |
| commit | 85e123c27d5cbc22cfdc01de1e2ca1d9003a02d0 (patch) | |
| tree | ac5f5270006dc9c408fb1393a6b5f16dcd949431 | |
| parent | 1ee88de395c3ad6791c4baeba40e83b6ec97657a (diff) | |
dm mirror log: round up region bitmap size to BITS_PER_LONG
The code in dm-log rounds up bitset_size to 32 bits. It then uses
find_next_zero_bit_le on the allocated region. find_next_zero_bit_le
accesses the bitmap using unsigned long pointers. So, on 64-bit
architectures, it may access 4 bytes beyond the allocated size.
Fix this bug by rounding up bitset_size to BITS_PER_LONG.
This bug was found by running the lvm2 testsuite with kasan.
Fixes: 29121bd0b00e ("[PATCH] dm mirror log: bitset_size fix")
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
| -rw-r--r-- | drivers/md/dm-log.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c index 06f328928a7f..2dda05aada23 100644 --- a/drivers/md/dm-log.c +++ b/drivers/md/dm-log.c @@ -415,8 +415,7 @@ static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti, /* * Work out how many "unsigned long"s we need to hold the bitset. */ - bitset_size = dm_round_up(region_count, - sizeof(*lc->clean_bits) << BYTE_SHIFT); + bitset_size = dm_round_up(region_count, BITS_PER_LONG); bitset_size >>= BYTE_SHIFT; lc->bitset_uint32_count = bitset_size / sizeof(*lc->clean_bits); |