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>
diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index b64f20d..13cfa81 100644
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -1962,7 +1962,7 @@
* 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);
}