[05/65] ALSA: HDA: Fix Oops caused by dereference NULL pointer
From: Steven Rostedt
Date: Mon Jun 03 2013 - 18:25:17 EST
3.6.11.5 stable review patch.
If anyone has any objections, please let me know.
------------------
From: Wang YanQing <udknight@xxxxxxxxx>
[ Upstream commit 2195b063f6609e4c6268f291683902f25eaf9aa6 ]
The interrupt handler azx_interrupt will call azx_update_rirb,
which may call snd_hda_queue_unsol_event, snd_hda_queue_unsol_event
will dereference chip->bus pointer.
The problem is we alloc chip->bus in azx_codec_create
which will be called after we enable IRQ and enable unsolicited
event in azx_probe.
This will cause Oops due dereference NULL pointer. I meet it, good luck:)
[Rearranged the NULL check before the tracepoint and added another
NULL check of bus->workq -- tiwai]
Signed-off-by: Wang YanQing <udknight@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
sound/pci/hda/hda_codec.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 558b6b0..693e890 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -609,6 +609,9 @@ int snd_hda_queue_unsol_event(struct hda_bus *bus, u32 res, u32 res_ex)
struct hda_bus_unsolicited *unsol;
unsigned int wp;
+ if (!bus || !bus->workq)
+ return 0;
+
trace_hda_unsol_event(bus, res, res_ex);
unsol = bus->unsol;
if (!unsol)
--
1.7.10.4
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