ALSA: rawmidi: Remove kernel WARNING for NULL user-space buffer check

commit cc85f7a634cfaf9f0713c6aa06d08817424db37a upstream.

NULL user-space buffer can be passed even in a normal path, thus it's
not good to spew a kernel warning with stack trace at each time.
Just drop snd_BUG_ON() macro usage there.

BugLink: http://lkml.kernel.org/r/CACT4Y+YfVJ3L+q0i-4vyQVyyPD7V=OMX0PWPi29x9Bo3QaBLdw@mail.gmail.com
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index 1bb95ae..2606592 100644 (file)
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -1162,7 +1162,7 @@ static long snd_rawmidi_kernel_write1(struct snd_rawmidi_substream *substream,
        long count1, result;
        struct snd_rawmidi_runtime *runtime = substream->runtime;
 
-       if (snd_BUG_ON(!kernelbuf && !userbuf))
+       if (!kernelbuf && !userbuf)
                return -EINVAL;
        if (snd_BUG_ON(!runtime->buffer))
                return -EINVAL;