| Message ID | 1445998534-38246-1-git-send-email-koro.chen@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, 2015-10-28 at 10:15 +0800, Koro Chen wrote: > During suspend/resume, there is a flow that if a driver does not support > SNDRV_PCM_INFO_RESUME, it will fail at snd_pcm_resume(), and user space > can then issue SNDRV_PCM_IOCTL_PREPARE to let audio continue to play. > > However, in dpcm_be_dai_prepare() it only allows BEs to be prepared > in state SND_SOC_DPCM_STATE_HW_PARAMS or SND_SOC_DPCM_STATE_STOP. > The BE state will then stay in SND_SOC_DPCM_STATE_SUSPEND, consequently > dpcm_be_dai_shutdown() is skipped in the end of playback and > be_substream->runtime is not cleared while this runtime is actually freed > by snd_pcm_detach_substream(). If another suspend comes, a NULL pointer > dereference will happen in snd_pcm_suspend() when accessing > BE substream's runtime. > > Signed-off-by: Koro Chen <koro.chen@mediatek.com> Acked-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c index 3173958..5c41a58 100644 --- a/sound/soc/soc-pcm.c +++ b/sound/soc/soc-pcm.c @@ -2117,7 +2117,8 @@ int dpcm_be_dai_prepare(struct snd_soc_pcm_runtime *fe, int stream) continue; if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_PARAMS) && - (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP)) + (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP) && + (be->dpcm[stream].state != SND_SOC_DPCM_STATE_SUSPEND)) continue; dev_dbg(be->dev, "ASoC: prepare BE %s\n",
During suspend/resume, there is a flow that if a driver does not support SNDRV_PCM_INFO_RESUME, it will fail at snd_pcm_resume(), and user space can then issue SNDRV_PCM_IOCTL_PREPARE to let audio continue to play. However, in dpcm_be_dai_prepare() it only allows BEs to be prepared in state SND_SOC_DPCM_STATE_HW_PARAMS or SND_SOC_DPCM_STATE_STOP. The BE state will then stay in SND_SOC_DPCM_STATE_SUSPEND, consequently dpcm_be_dai_shutdown() is skipped in the end of playback and be_substream->runtime is not cleared while this runtime is actually freed by snd_pcm_detach_substream(). If another suspend comes, a NULL pointer dereference will happen in snd_pcm_suspend() when accessing BE substream's runtime. Signed-off-by: Koro Chen <koro.chen@mediatek.com> --- sound/soc/soc-pcm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)