Draft: CVE-2024-38388: ALSA: hda/cs_dsp_ctl: Use private_free for control cleanup
requested to merge redhat/red-hat-ci-tools/kernel/bot-branches/centos-stream-9:backport-RHEL-44390-centos-stream-9-main into main
JIRA: https://issues.redhat.com/browse/RHEL-44390
CVE: CVE-2024-38388
ALSA: hda/cs_dsp_ctl: Use private_free for control cleanup
Use the control private_free callback to free the associated data
block. This ensures that the memory won't leak, whatever way the
control gets destroyed.
The original implementation didn't actually remove the ALSA
controls in hda_cs_dsp_control_remove(). It only freed the internal
tracking structure. This meant it was possible to remove/unload the
amp driver while leaving its ALSA controls still present in the
soundcard. Obviously attempting to access them could cause segfaults
or at least dereferencing stale pointers.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 3233b978af23 ("ALSA: hda: hda_cs_dsp_ctl: Add Library to support CS_DSP ALSA controls")
Link: https://lore.kernel.org/r/20240508095627.44476-1-rf@opensource.cirrus.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
(cherry picked from commit 172811e3a557d8681a5e2d0f871dc04a2d17eb13)Signed-off-by: cki-backport-bot cki-ci-bot+cki-gitlab-backport-bot@redhat.com