From 2cdc460fe5f873486b32c986f866d0d6a2812417 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 12 Jan 2016 12:38:02 +0100 Subject: [PATCH] ALSA: seq: Fix missing NULL check at remove_events ioctl Orabug: 23330522 commit 030e2c78d3a91dd0d27fef37e91950dde333eba1 upstream. 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 Tested-by: Dmitry Vyukov Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman (cherry picked from commit 9a6003a362acb814fea7422209be344b822b047a) Signed-off-by: Dan Duval --- sound/core/seq/seq_clientmgr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c index edbdab85fc02..bd4741442909 100644 --- a/sound/core/seq/seq_clientmgr.c +++ b/sound/core/seq/seq_clientmgr.c @@ -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); } -- 2.50.1