This is a note to let you know that I've just added the patch titled
ALSA: memalloc: Catch call with NULL snd_dma_buffer pointer
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
alsa-memalloc-catch-call-with-null-snd_dma_buffer-po.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d4533fcc7b1628350fca4a94519ce718acb166a3
Author: Takashi Iwai <tiwai@xxxxxxx>
Date: Fri Nov 5 11:21:03 2021 +0100
ALSA: memalloc: Catch call with NULL snd_dma_buffer pointer
[ Upstream commit dce9446192439eaac81c21f517325fb473735e53 ]
Although we've covered all calls with NULL dma buffer pointer, so far,
there may be still some else in the wild. For catching such a case
more easily, add a WARN_ON_ONCE() in snd_dma_get_ops().
Fixes: 37af81c5998f ("ALSA: core: Abstract memory alloc helpers")
Link: https://lore.kernel.org/r/20211105102103.28148-1-tiwai@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/sound/core/memalloc.c b/sound/core/memalloc.c
index 0b8a1c3eae1b4..2d842982576bb 100644
--- a/sound/core/memalloc.c
+++ b/sound/core/memalloc.c
@@ -494,6 +494,8 @@ static const struct snd_malloc_ops *dma_ops[] = {
static const struct snd_malloc_ops *snd_dma_get_ops(struct snd_dma_buffer *dmab)
{
+ if (WARN_ON_ONCE(!dmab))
+ return NULL;
if (WARN_ON_ONCE(dmab->dev.type <= SNDRV_DMA_TYPE_UNKNOWN ||
dmab->dev.type >= ARRAY_SIZE(dma_ops)))
return NULL;
