From: Mikulas Patocka <mpatocka@redhat.com>
Date: Mon, 18 Mar 2024 17:35:06 +0000 (+0100)
Subject: dm-integrity: fix a memory leak when rechecking the data
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=20e21c3c0195d915f33bc7321ee6b362177bf5bf;p=people%2Faperard%2Flinux.git

dm-integrity: fix a memory leak when rechecking the data

[ 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>
---

diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index 3da4359f51645..e1bf91faa462b 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -1856,12 +1856,12 @@ again:
 			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;
 			}