[PATCH 6.7 687/713] dm-integrity: fix a memory leak when rechecking the data

Sasha Levin
2024-03-24T22:58:46Z

From: Mikulas Patocka <mpatocka@redhat.com>

[ Upstream commit 55e565c42dce81a4e49c13262d5bc4eb4c2e588a ]

Memory for the "checksums" pointer will leak if the data is rechecked
after checksum failure (because the associated kfree won't happen due
to 'goto skip_io').

Fix this by freeing the checksums memory before recheck, and just use
the "checksum_onstack" memory for storing checksum during recheck.

Fixes: c88f5e553fe3 ("dm-integrity: recheck the integrity tag after a failure")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/md/dm-integrity.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index e8e8fc33d3440..cc834c8423bcf 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -1848,12 +1848,12 @@ static void integrity_metadata(struct work_struct *w)
r = dm_integrity_rw_tag(ic, checksums, &dio->metadata_block, &dio->metadata_offset,
checksums_ptr - checksums, dio->op == REQ_OP_READ ? TAG_CMP : TAG_WRITE);
if (unlikely(r)) {
+ if (likely(checksums != checksums_onstack))
+ kfree(checksums);
if (r > 0) {
- integrity_recheck(dio, checksums);
+ integrity_recheck(dio, checksums_onstack);
goto skip_io;
}
- if (likely(checksums != checksums_onstack))
- kfree(checksums);
goto error;
}

--
2.43.0