From: Ma Ke <make_ruc2021@163.com>
To: mripard@kernel.org, paul.kocialkowski@bootlin.com,
mchehab@kernel.org, gregkh@linuxfoundation.org, wens@csie.org,
jernej.skrabec@gmail.com, samuel@sholland.org
Cc: linux-media@vger.kernel.org, linux-staging@lists.linux.dev,
linux-arm-kernel@lists.infradead.org,
linux-sunxi@lists.linux.dev, Ma Ke <make_ruc2021@163.com>
Subject: [PATCH] media: cedrus: fix use after free bug in cedrus_remove due to race condition
Date: Fri, 15 Sep 2023 19:40:38 +0800 [thread overview]
Message-ID: <20230915114038.3407953-1-make_ruc2021@163.com> (raw)
In cedrus_probe, dev->watchdog_work is bound with cedrus_watchdog. Then
cedrus_device_run may be called to start the work.
If we close the file or remove the module which will call cedrus_release and
cedrus_remove to make cleanup, there may be an unfinished work. The possible
sequence is as follows, which will cause a typical UAF bug.
The same thing will happen in cedrus_release, and use ctx after freeing it.
Fix it by canceling the work before cleanup in cedrus_release.
Signed-off-by: Ma Ke <make_ruc2021@163.com>
---
drivers/staging/media/sunxi/cedrus/cedrus.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/staging/media/sunxi/cedrus/cedrus.c b/drivers/staging/media/sunxi/cedrus/cedrus.c
index 8e248d4a0aec..0a2cb615d717 100644
--- a/drivers/staging/media/sunxi/cedrus/cedrus.c
+++ b/drivers/staging/media/sunxi/cedrus/cedrus.c
@@ -404,6 +404,8 @@ static int cedrus_release(struct file *file)
struct cedrus_ctx *ctx = container_of(file->private_data,
struct cedrus_ctx, fh);
+ cancel_delayed_work_sync(&ctx->dev->watchdog_work);
+
mutex_lock(&dev->dev_mutex);
v4l2_fh_del(&ctx->fh);
--
2.37.2
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next reply other threads:[~2023-09-15 11:41 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-15 11:40 Ma Ke [this message]
2023-09-15 12:33 ` [PATCH] media: cedrus: fix use after free bug in cedrus_remove due to race condition Dan Carpenter
-- strict thread matches above, loose matches on Subject: below --
2023-03-08 3:23 Zheng Wang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230915114038.3407953-1-make_ruc2021@163.com \
--to=make_ruc2021@163.com \
--cc=gregkh@linuxfoundation.org \
--cc=jernej.skrabec@gmail.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-media@vger.kernel.org \
--cc=linux-staging@lists.linux.dev \
--cc=linux-sunxi@lists.linux.dev \
--cc=mchehab@kernel.org \
--cc=mripard@kernel.org \
--cc=paul.kocialkowski@bootlin.com \
--cc=samuel@sholland.org \
--cc=wens@csie.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox