path: root/drivers/md/dm-integrity.c
diff options
authorMikulas Patocka <mpatocka@redhat.com>2019-03-13 07:56:02 -0400
committerMike Snitzer <snitzer@redhat.com>2019-04-01 16:11:11 -0400
commit0d74e6a3b6421d98eeafbed26f29156d469bc0b5 (patch)
tree13b9ab66fe1553126777b6afb114612743b6778c /drivers/md/dm-integrity.c
parentLinux 5.1-rc3 (diff)
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@vger.kernel.org # v4.12+ Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md/dm-integrity.c')
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index d57d997a52c8..33fac437569f 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -3185,7 +3185,7 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv)
journal_watermark = val;
else if (sscanf(opt_string, "commit_time:%u%c", &val, &dummy) == 1)
sync_msec = val;
- else if (!memcmp(opt_string, "meta_device:", strlen("meta_device:"))) {
+ else if (!strncmp(opt_string, "meta_device:", strlen("meta_device:"))) {
if (ic->meta_dev) {
dm_put_device(ti, ic->meta_dev);
ic->meta_dev = NULL;
@@ -3204,17 +3204,17 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv)
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)