Messages in this thread Patch in this message | | | Date | Tue, 7 May 2013 11:27:33 +0800 | From | Wang YanQing <> | Subject | [PATCH]ALSA: HDA: Fix Oops caused by dereference NULL pointer |
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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:)
Signed-off-by: Wang YanQing <udknight@gmail.com> --- 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 622f726..9c76752 100644 --- a/sound/pci/hda/hda_codec.c +++ b/sound/pci/hda/hda_codec.c @@ -618,6 +618,9 @@ int snd_hda_queue_unsol_event(struct hda_bus *bus, u32 res, u32 res_ex) unsigned int wp; trace_hda_unsol_event(bus, res, res_ex); + if (!bus) + return 0; + unsol = bus->unsol; if (!unsol) return 0; -- 1.7.12.4.dirty
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