At Wed, 8 Oct 2014 12:32:46 +0300, Dan Carpenter wrote:

Hello Takashi Iwai,

The patch 5100cd07d43a: "ALSA: hda/realtek - Allow NULL bus->pci" from Feb 15, 2014, leads to the following static checker warning:

sound/pci/hda/patch_realtek.c:5371 patch_alc269() warn: variable dereferenced before check 'codec->bus->pci' (see line 5364)

sound/pci/hda/patch_realtek.c 5363 if (has_cdefine_beep(codec)) ^^^^^ We actually dereference "codec->bus->pci" inside the call to has_cdefine_beep().

Indeed. I fixed snd_pci_quirk_lookup() itself to accept NULL pointer as a generic fix in below.

Thanks!

Takashi

-- 8< -- From: Takashi Iwai tiwai@suse.de Subject: [PATCH] ALSA: Allow pass NULL dev for snd_pci_quirk_lookup()

Add a NULL check in snd_pci_quirk_lookup() so that NULL can be passed as a pci_dev pointer. This fixes the possible NULL dereferences in HD-audio drivers.

Reported-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/core/misc.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/sound/core/misc.c b/sound/core/misc.c index 30e027ecf4da..f2e8226c88fb 100644 --- a/sound/core/misc.c +++ b/sound/core/misc.c @@ -145,6 +145,8 @@ EXPORT_SYMBOL(snd_pci_quirk_lookup_id); const struct snd_pci_quirk * snd_pci_quirk_lookup(struct pci_dev *pci, const struct snd_pci_quirk *list) { + if (!pci) + return NULL; return snd_pci_quirk_lookup_id(pci->subsystem_vendor, pci->subsystem_device, list);