[PULL,5/8] audio: fix wavcapture segfault

Commit Message

Gerd Hoffmann May 26, 2020, 7:56 a.m. UTC

From: Bruce Rogers <[e-mail]>

Commit 571a8c522e caused the HMP wavcapture command to segfault when
processing audio data in audio_pcm_sw_write(), where a NULL
sw->hw->pcm_ops is dereferenced. This fix checks that the pointer is
valid before dereferincing it. A similar fix is also made in the
parallel function audio_pcm_sw_read().

Fixes: 571a8c522e (audio: split ctl_* functions into enable_* and
volume_*)
Signed-off-by: Bruce Rogers <[e-mail]>
Reviewed-by: Philippe Mathieu-Daudé <[e-mail]>
Message-id: [e-mail]
Signed-off-by: Gerd Hoffmann <[e-mail]>
---
 audio/audio.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Patch

diff --git a/audio/audio.c b/audio/audio.c
index 95d9fb16caa5..ce8c6dec5f47 100644
--- a/audio/audio.c
+++ b/audio/audio.c
@@ -649,7 +649,7 @@  static size_t audio_pcm_sw_read(SWVoiceIn *sw, void *buf, size_t size)
         total += isamp;
     }
 
-    if (!hw->pcm_ops->volume_in) {
+    if (hw->pcm_ops && !hw->pcm_ops->volume_in) {
         mixeng_volume (sw->buf, ret, &sw->vol);
     }
 
@@ -736,7 +736,7 @@  static size_t audio_pcm_sw_write(SWVoiceOut *sw, void *buf, size_t size)
     if (swlim) {
         sw->conv (sw->buf, buf, swlim);
 
-        if (!sw->hw->pcm_ops->volume_out) {
+        if (sw->hw->pcm_ops && !sw->hw->pcm_ops->volume_out) {
             mixeng_volume (sw->buf, swlim, &sw->vol);
         }
     }