[PATCH 4.4 42/62] ALSA: pcm: oss: Remove superfluous WARN_ON() for mulaw sanity check

Greg Kroah-Hartman
2020-09-11T17:31:26Z

From: Takashi Iwai <tiwai@suse.de>

commit 949a1ebe8cea7b342085cb6a4946b498306b9493 upstream.

The PCM OSS mulaw plugin has a check of the format of the counter part
whether it's a linear format. The check is with snd_BUG_ON() that
emits WARN_ON() when the debug config is set, and it confuses
syzkaller as if it were a serious issue. Let's drop snd_BUG_ON() for
avoiding that.

While we're at it, correct the error code to a more suitable, EINVAL.

Reported-by: syzbot+23b22dc2e0b81cbfcc95@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200901131802.18157-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
sound/core/oss/mulaw.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/sound/core/oss/mulaw.c
+++ b/sound/core/oss/mulaw.c
@@ -329,8 +329,8 @@ int snd_pcm_plugin_build_mulaw(struct sn
snd_BUG();
return -EINVAL;
}
- if (snd_BUG_ON(!snd_pcm_format_linear(format->format)))
- return -ENXIO;
+ if (!snd_pcm_format_linear(format->format))
+ return -EINVAL;

err = snd_pcm_plugin_build(plug, "Mu-Law<->linear conversion",
src_format, dst_format,