From: Mikulas Patocka <mpatocka@redhat.com>
Date: Fri, 3 Apr 2020 13:05:50 -0400
Subject: [PATCH] dm integrity: fix logic bug in integrity tag testing
Git-commit: 8267d8fb4819afa76b2a54dca48efdda6f0b1910
Patch-mainline: v5.7-rc1
References: bsc#1175995,jsc#SLE-15608
If all the bytes are equal to DISCARD_FILLER, we want to accept the
buffer. If any of the bytes are different, we must do thorough
tag-by-tag checking.
The condition was inverted.
Fixes: 84597a44a9d8 ("dm integrity: add optional discard support")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Hannes Reinecke <hare@suse.com>
---
drivers/md/dm-integrity.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index 49fee5aecbc9..4094c47eca7f 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -1333,7 +1333,7 @@ static int dm_integrity_rw_tag(struct dm_integrity_c *ic, unsigned char *tag, se
if (likely(is_power_of_2(ic->tag_size))) {
if (unlikely(memcmp(dp, tag, to_copy)))
if (unlikely(!ic->discard) ||
- unlikely(!memchr_inv(dp, DISCARD_FILLER, to_copy))) {
+ unlikely(memchr_inv(dp, DISCARD_FILLER, to_copy) != NULL)) {
goto thorough_test;
}
} else {
--
2.16.4