Re: [PATCH] sound: fix PCM substream list

From: Takashi Iwai
Date: Thu Nov 23 2006 - 06:07:13 EST


At Thu, 23 Nov 2006 03:51:45 +0900,
Akinobu Mita wrote:
>
> If snd_pcm_new_stream() fails to initalize a substream (if
> snd_pcm_substream_proc_init() returns error), snd_pcm_new_stream()
> immediately return without unlinking that kfree()d substram.
>
> It causes oops when snd_pcm_free() iterates the list of substream to
> free them by invalid reference.
>
> Cc: Takashi Iwai <tiwai@xxxxxxx>
> Cc: Jaroslav Kysela <perex@xxxxxxx>
> Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>

Merged this one to ALSA tree, too.
Thanks.


Takashi

>
> ---
> sound/core/pcm.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> Index: work-fault-inject/sound/core/pcm.c
> ===================================================================
> --- work-fault-inject.orig/sound/core/pcm.c
> +++ work-fault-inject/sound/core/pcm.c
> @@ -638,6 +638,10 @@ int snd_pcm_new_stream(struct snd_pcm *p
> err = snd_pcm_substream_proc_init(substream);
> if (err < 0) {
> snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
> + if (prev == NULL)
> + pstr->substream = NULL;
> + else
> + prev->next = NULL;
> kfree(substream);
> return err;
> }
>
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/