sound: Fix esoteric double free in the dummy sound driver.

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / sound / drivers / dummy.c

diff --git a/sound/drivers/dummy.c b/sound/drivers/dummy.c
index c873243e6713d4b4349b3d7412f66727e2e10aaf..4f900d8b92ce9a783f481309f6300807f766a1fe 100644 (file)
--- a/sound/drivers/dummy.c
+++ b/sound/drivers/dummy.c
@@ -354,6 +354,7 @@ static int snd_card_dummy_playback_open(struct snd_pcm_substream *substream)
        if ((dpcm = new_pcm_stream(substream)) == NULL)
                return -ENOMEM;
        runtime->private_data = dpcm;
+       /* makes the infrastructure responsible for freeing dpcm */
        runtime->private_free = snd_card_dummy_runtime_free;
        runtime->hw = snd_card_dummy_playback;
        if (substream->pcm->device & 1) {
@@ -362,10 +363,8 @@ static int snd_card_dummy_playback_open(struct snd_pcm_substream *substream)
        }
        if (substream->pcm->device & 2)
                runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID);
-       if ((err = add_playback_constraints(runtime)) < 0) {
-               kfree(dpcm);
+       if ((err = add_playback_constraints(runtime)) < 0)
                return err;
-       }
 
        return 0;
 }
@@ -379,6 +378,7 @@ static int snd_card_dummy_capture_open(struct snd_pcm_substream *substream)
        if ((dpcm = new_pcm_stream(substream)) == NULL)
                return -ENOMEM;
        runtime->private_data = dpcm;
+       /* makes the infrastructure responsible for freeing dpcm */
        runtime->private_free = snd_card_dummy_runtime_free;
        runtime->hw = snd_card_dummy_capture;
        if (substream->pcm->device == 1) {
@@ -387,10 +387,8 @@ static int snd_card_dummy_capture_open(struct snd_pcm_substream *substream)
        }
        if (substream->pcm->device & 2)
                runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID);
-       if ((err = add_capture_constraints(runtime)) < 0) {
-               kfree(dpcm);
+       if ((err = add_capture_constraints(runtime)) < 0)
                return err;
-       }
 
        return 0;
 }