Commit a4d51cc7 authored by Cezary Rojewski's avatar Cezary Rojewski Committed by Zeng Heng
Browse files

ALSA: hda: Fix possible null-ptr-deref when assigning a stream 

mainline inclusion
from mainline-v6.7-rc1
commit f93dc90c2e8ed664985e366aa6459ac83cdab236
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9RFHM
CVE: CVE-2023-52806

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f93dc90c2e8ed664985e366aa6459ac83cdab236



--------------------------------

While AudioDSP drivers assign streams exclusively of HOST or LINK type,
nothing blocks a user to attempt to assign a COUPLED stream. As
supplied substream instance may be a stub, what is the case when
code-loading, such scenario ends with null-ptr-deref.

Signed-off-by: default avatarCezary Rojewski <cezary.rojewski@intel.com>
Link: https://lore.kernel.org/r/20231006102857.749143-2-cezary.rojewski@intel.com


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Signed-off-by: default avatarZeng Heng <zengheng4@huawei.com>
parent 505199cb

sound/hda/hdac_stream.c

+4 −2
Original line number Diff line number Diff line
@@ -241,8 +241,10 @@ struct hdac_stream *snd_hdac_stream_assign(struct hdac_bus *bus, 
	struct hdac_stream *res = NULL;



	/* make a non-zero unique key for the substream */

	int key = (substream->pcm->device << 16) | (substream->number << 2) |

		(substream->stream + 1);

	int key = (substream->number << 2) | (substream->stream + 1);



	if (substream->pcm)

		key |= (substream->pcm->device << 16);



	list_for_each_entry(azx_dev, &bus->stream_list, list) {

		if (azx_dev->direction != substream->stream)