altera-stapl: check for a null key before strcasecmp'ing it

Currently the null check on key is occurring after the strcasecmp on
the key, hence there is a potential null pointer dereference on key.
Fix this by checking if key is null first. Also replace the == 0
check on strcasecmp with just the ! operator.

Detected by CoverityScan, CID#1248787 ("Dereference before null check")

Fixes: fa766c9be5 ("[media] Altera FPGA firmware download module")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Colin Ian King 2018-11-24 12:34:10 +00:00 committed by Greg Kroah-Hartman
parent 5323ac5177
commit 9ccb645683

View file

@ -2176,8 +2176,7 @@ static int altera_get_note(u8 *p, s32 program_size,
key_ptr = &p[note_strings +
get_unaligned_be32(
&p[note_table + (8 * i)])];
if ((strncasecmp(key, key_ptr, strlen(key_ptr)) == 0) &&
(key != NULL)) {
if (key && !strncasecmp(key, key_ptr, strlen(key_ptr))) {
status = 0;
value_ptr = &p[note_strings +