Hi.
Here I'm sending the patch backported for the kernel 4.14.
Mikulas
>From gregkh@xxxxxxxxxxxxxxxxxxx Mon Apr 15 12:38:03 2019
Date: Mon, 15 Apr 2019 18:37:16 +0200
From: gregkh@xxxxxxxxxxxxxxxxxxx
To: mpatocka@xxxxxxxxxx, snitzer@xxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Subject: FAILED: patch "[PATCH] dm integrity: change memcmp to strncmp in dm_integrity_ctr" failed to apply to 4.14-stable tree
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 0d74e6a3b6421d98eeafbed26f29156d469bc0b5 Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Date: Wed, 13 Mar 2019 07:56:02 -0400
Subject: [PATCH] dm integrity: change memcmp to strncmp in dm_integrity_ctr
If the string opt_string is small, the function memcmp can access bytes
that are beyond the terminating nul character. In theory, it could cause
segfault, if opt_string were located just below some unmapped memory.
Change from memcmp to strncmp so that we don't read bytes beyond the end
of the string.
Cc: stable@xxxxxxxxxxxxxxx # v4.12+
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
---
drivers/md/dm-integrity.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
Index: linux-stable/drivers/md/dm-integrity.c
===================================================================
--- linux-stable.orig/drivers/md/dm-integrity.c 2019-04-16 10:41:05.000000000 +0200
+++ linux-stable/drivers/md/dm-integrity.c 2019-04-16 10:41:05.000000000 +0200
@@ -2889,17 +2889,17 @@ static int dm_integrity_ctr(struct dm_ta
goto bad;
}
ic->sectors_per_block = val >> SECTOR_SHIFT;
- } else if (!memcmp(opt_string, "internal_hash:", strlen("internal_hash:"))) {
+ } else if (!strncmp(opt_string, "internal_hash:", strlen("internal_hash:"))) {
r = get_alg_and_key(opt_string, &ic->internal_hash_alg, &ti->error,
"Invalid internal_hash argument");
if (r)
goto bad;
- } else if (!memcmp(opt_string, "journal_crypt:", strlen("journal_crypt:"))) {
+ } else if (!strncmp(opt_string, "journal_crypt:", strlen("journal_crypt:"))) {
r = get_alg_and_key(opt_string, &ic->journal_crypt_alg, &ti->error,
"Invalid journal_crypt argument");
if (r)
goto bad;
- } else if (!memcmp(opt_string, "journal_mac:", strlen("journal_mac:"))) {
+ } else if (!strncmp(opt_string, "journal_mac:", strlen("journal_mac:"))) {
r = get_alg_and_key(opt_string, &ic->journal_mac_alg, &ti->error,
"Invalid journal_mac argument");
if (r)
