[ALSA] Fix possible invalid memory access in PCM core
snd_internval_list() may access invalid memory in the case count = 0
is given. It shouldn't be passed, but it'd better to make the code
a bit more robust.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index b336797..9fefcaa 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -781,6 +781,11 @@
{
unsigned int k;
int changed = 0;
+
+ if (!count) {
+ i->empty = 1;
+ return -EINVAL;
+ }
for (k = 0; k < count; k++) {
if (mask && !(mask & (1 << k)))
continue;