From: Takashi Iwai <tiwai@suse.de>
Date: Wed, 8 Oct 2014 10:08:38 +0000 (+0200)
Subject: ALSA: Allow pass NULL dev for snd_pci_quirk_lookup()
X-Git-Tag: firefly_0821_release~176^2~2610^2~84
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e5b50ada76f44c8742a123813689bff4db062a5a;p=firefly-linux-kernel-4.4.55.git

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>
---

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);