ALSA: seq: Fix missing NULL check at remove_events ioctl

snd_seq_ioctl_remove_events() calls snd_seq_fifo_clear()
unconditionally even if there is no FIFO assigned, and this leads to
an Oops due to NULL dereference.  The fix is just to add a proper NULL
check.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2016-01-12 12:38:02 +01:00
parent 5c06d68bc2
commit 030e2c78d3
1 changed files with 1 additions and 1 deletions

View File

@ -1962,7 +1962,7 @@ static int snd_seq_ioctl_remove_events(struct snd_seq_client *client,
* No restrictions so for a user client we can clear
* the whole fifo
*/
if (client->type == USER_CLIENT)
if (client->type == USER_CLIENT && client->data.user.fifo)
snd_seq_fifo_clear(client->data.user.fifo);
}