From: Mikulas Patocka mpatocka@redhat.com
commit 98dba02d9a93eec11bffbb93c7c51624290702d2 upstream.
This command will crash with NULL pointer dereference: dmsetup create flakey --table \ "0 `blockdev --getsize /dev/ram0` flakey /dev/ram0 0 0 1 2 corrupt_bio_byte 512"
Fix the crash by checking if arg_name is non-NULL before comparing it.
Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka mpatocka@redhat.com Signed-off-by: Mike Snitzer snitzer@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/md/dm-flakey.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/md/dm-flakey.c +++ b/drivers/md/dm-flakey.c @@ -124,9 +124,9 @@ static int parse_features(struct dm_arg_ * Direction r or w? */ arg_name = dm_shift_arg(as); - if (!strcasecmp(arg_name, "w")) + if (arg_name && !strcasecmp(arg_name, "w")) fc->corrupt_bio_rw = WRITE; - else if (!strcasecmp(arg_name, "r")) + else if (arg_name && !strcasecmp(arg_name, "r")) fc->corrupt_bio_rw = READ; else { ti->error = "Invalid corrupt bio direction (r or w)";