From: Jaroslav Kysela Date: Fri, 13 Jan 2023 08:53:11 +0000 (+0100) Subject: ALSA: usb-audio: Fix possible NULL pointer dereference in snd_usb_pcm_has_fixed_rate() X-Git-Tag: dma-mapping-6.3-2022-02-27~171^2~1 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=92a9c0ad86d47ff4cce899012e355c400f02cfb8;p=users%2Fhch%2Fdma-mapping.git ALSA: usb-audio: Fix possible NULL pointer dereference in snd_usb_pcm_has_fixed_rate() The subs function argument may be NULL, so do not use it before the NULL check. Fixes: 291e9da91403 ("ALSA: usb-audio: Always initialize fixed_rate in snd_usb_find_implicit_fb_sync_format()") Reported-by: coverity-bot Link: https://lore.kernel.org/alsa-devel/202301121424.4A79A485@keescook/ Signed-off-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20230113085311.623325-1-perex@perex.cz Signed-off-by: Takashi Iwai --- diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index 1f72960d0d53..d959da7a1afb 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -160,11 +160,12 @@ find_substream_format(struct snd_usb_substream *subs, bool snd_usb_pcm_has_fixed_rate(struct snd_usb_substream *subs) { const struct audioformat *fp; - struct snd_usb_audio *chip = subs->stream->chip; + struct snd_usb_audio *chip; int rate = -1; if (!subs) return false; + chip = subs->stream->chip; if (!(chip->quirk_flags & QUIRK_FLAG_FIXED_RATE)) return false; list_for_each_entry(fp, &subs->fmt_list, list) {