From: Hans Verkuil <hverkuil-cisco@xs4all.nl> stable inclusion from stable-v4.19.316 commit d2cfbc5298add5e0c6cfe8b343f73dfdf01c8b1c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I8YC89 CVE: CVE-2024-23848 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 42bcaacae924bf18ae387c3f78c202df0b739292 ] When cec_release() uses fh->msgs it has to take fh->lock, otherwise the list can get corrupted. Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Reported-by: Yang, Chenyuan <cy54@illinois.edu> Closes: https://lore.kernel.org/linux-media/PH7PR11MB57688E64ADE4FE82E658D86DA09EA@P... Fixes: ca684386e6e2 ("[media] cec: add HDMI CEC framework (api)") Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com> --- drivers/media/cec/cec-api.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/media/cec/cec-api.c b/drivers/media/cec/cec-api.c index b2b3f779592fd..d4c848c2f3764 100644 --- a/drivers/media/cec/cec-api.c +++ b/drivers/media/cec/cec-api.c @@ -660,6 +660,8 @@ static int cec_release(struct inode *inode, struct file *filp) list_del(&data->xfer_list); } mutex_unlock(&adap->lock); + + mutex_lock(&fh->lock); while (!list_empty(&fh->msgs)) { struct cec_msg_entry *entry = list_first_entry(&fh->msgs, struct cec_msg_entry, list); @@ -677,6 +679,7 @@ static int cec_release(struct inode *inode, struct file *filp) kfree(entry); } } + mutex_unlock(&fh->lock); kfree(fh); cec_put_device(devnode); -- 2.34.1