[ALSA] pcm - Fix zero-division in 32bit compat layer

PCM Midlevel
Fixed zero-division bug in PCM 32bit compat layer.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 8 insertions, 3 deletions

diff --git a/sound/core/pcm_compat.c b/sound/core/pcm_compat.c
index eef94a15f50a..4b6307df846d 100644
--- a/sound/core/pcm_compat.c
+++ b/sound/core/pcm_compat.c
@@ -144,7 +144,7 @@ static int snd_pcm_ioctl_sw_params_compat(snd_pcm_substream_t *substream,
         err = snd_pcm_sw_params(substream, &params);
         if (err < 0)
                 return err;
-        if (put_user(boundary, &src->boundary))
+        if (boundary && put_user(boundary, &src->boundary))
                 return -EFAULT;
         return err;
 }
@@ -252,8 +252,11 @@ static int snd_pcm_ioctl_hw_params_compat(snd_pcm_substream_t *substream,
                 goto error;
         }
 
-        if (! refine)
-                runtime->boundary = recalculate_boundary(runtime);
+        if (! refine) {
+                unsigned int new_boundary = recalculate_boundary(runtime);
+                if (new_boundary)
+                        runtime->boundary = new_boundary;
+        }
  error:
         kfree(data);
         return err;
@@ -408,6 +411,8 @@ static int snd_pcm_ioctl_sync_ptr_compat(snd_pcm_substream_t *substream,
         status = runtime->status;
         control = runtime->control;
         boundary = recalculate_boundary(runtime);
+        if (! boundary)
+                boundary = 0x7fffffff;
         snd_pcm_stream_lock_irq(substream);
         /* FIXME: we should consider the boundary for the sync from app */
         if (!(sflags & SNDRV_PCM_SYNC_PTR_APPL))