diff options
| author | Genjian Zhang <zhanggenjian@kylinos.cn> | 2026-07-11 18:05:26 +0800 |
|---|---|---|
| committer | Mikulas Patocka <mpatocka@redhat.com> | 2026-07-11 15:18:51 +0200 |
| commit | 4b22d0801fadfcae2e106e6ba32e49439c7c7ebf (patch) | |
| tree | 07a60ca856b0d5ebce79047ef0cf7772e89695c2 | |
| parent | 386df1a57b631c456d14f857cb0c0c2e11c16bef (diff) | |
dm thin metadata: fix superblock refcount leak on snapshot shadow failure
__reserve_metadata_snap() increments THIN_SUPERBLOCK_LOCATION in the
metadata space map before shadowing it. When dm_tm_shadow_block()
fails, a reference is leaked in the metadata space map.
Fix by adding the missing dm_sm_dec_block().
Signed-off-by: Genjian Zhang <zhanggenjian@kylinos.cn>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: cc8394d86f04 ("dm thin: provide userspace access to pool metadata")
Cc: stable@vger.kernel.org
| -rw-r--r-- | drivers/md/dm-thin-metadata.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c index a010ff1e5c92..e60e1326376a 100644 --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -1362,8 +1362,10 @@ static int __reserve_metadata_snap(struct dm_pool_metadata *pmd) dm_sm_inc_block(pmd->metadata_sm, THIN_SUPERBLOCK_LOCATION); r = dm_tm_shadow_block(pmd->tm, THIN_SUPERBLOCK_LOCATION, &sb_validator, ©, &inc); - if (r) + if (r) { + dm_sm_dec_block(pmd->metadata_sm, THIN_SUPERBLOCK_LOCATION); return r; + } BUG_ON(!inc); |