iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ALSA: pcm: Check for null pointer of pointer substream before dereferencing it

Browse Source 
commit 011b559be832194f992f73d6c0d5485f5925a10b upstream.

Pointer substream is being dereferenced on the assignment of pointer card
before substream is being null checked with the macro PCM_RUNTIME_CHECK.
Although PCM_RUNTIME_CHECK calls BUG_ON, it still is useful to perform the
the pointer check before card is assigned.

Fixes: d4cfb30fce03 ("ALSA: pcm: Set per-card upper limit of PCM buffer allocations")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220424205945.1372247-1-colin.i.king@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Colin Ian King 2022-04-24 21:59:45 +01:00 committed by Greg Kroah-Hartman
parent e8bf830efa
commit b2421a196c
1 changed files with 2 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
sound/core/pcm_memory.c
View File

@ -401,7 +401,6 @@ EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);
*/
int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
{
struct snd_card *card = substream->pcm->card;
struct snd_pcm_runtime *runtime;
if (PCM_RUNTIME_CHECK(substream))
@ -410,6 +409,8 @@ int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
if (runtime->dma_area == NULL)
return 0;
if (runtime->dma_buffer_p != &substream->dma_buffer) {
struct snd_card *card = substream->pcm->card;
/* it's a newly allocated buffer. release it now. */
do_free_pages(card, runtime->dma_buffer_p);
kfree(runtime->dma_buffer_p);