FAILED: patch "[PATCH] media: mc: Clear minor number before put device" failed to apply to 6.12-stable tree

FAILED: patch "[PATCH] media: mc: Clear minor number before put device" failed to apply to 6.12-stable tree

[gregkh]

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 8cfc8cec1b4da88a47c243a11f384baefd092a50
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025101336-tannery-reverb-5975@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 8cfc8cec1b4da88a47c243a11f384baefd092a50 Mon Sep 17 00:00:00 2001
From: Edward Adam Davis <eadavis@qq.com>
Date: Wed, 10 Sep 2025 09:15:27 +0800
Subject: [PATCH] media: mc: Clear minor number before put device

The device minor should not be cleared after the device is released.

Fixes: 9e14868dc952 ("media: mc: Clear minor number reservation at unregistration time")
Cc: stable@vger.kernel.org
Reported-by: syzbot+031d0cfd7c362817963f@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=031d0cfd7c362817963f
Tested-by: syzbot+031d0cfd7c362817963f@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>

diff --git a/drivers/media/mc/mc-devnode.c b/drivers/media/mc/mc-devnode.c
index 0d01cbae98f2..6daa7aa99442 100644
--- a/drivers/media/mc/mc-devnode.c
+++ b/drivers/media/mc/mc-devnode.c
@@ -276,13 +276,10 @@ void media_devnode_unregister(struct media_devnode *devnode)
 	/* Delete the cdev on this minor as well */
 	cdev_device_del(&devnode->cdev, &devnode->dev);
 	devnode->media_dev = NULL;
+	clear_bit(devnode->minor, media_devnode_nums);
 	mutex_unlock(&media_devnode_lock);
 
 	put_device(&devnode->dev);
-
-	mutex_lock(&media_devnode_lock);
-	clear_bit(devnode->minor, media_devnode_nums);
-	mutex_unlock(&media_devnode_lock);
 }
 
 /*

[PATCH 6.12.y] media: mc: Clear minor number before put device

[Sasha Levin]

From: Edward Adam Davis <eadavis@qq.com>

[ Upstream commit 8cfc8cec1b4da88a47c243a11f384baefd092a50 ]

The device minor should not be cleared after the device is released.

Fixes: 9e14868dc952 ("media: mc: Clear minor number reservation at unregistration time")
Cc: stable@vger.kernel.org
Reported-by: syzbot+031d0cfd7c362817963f@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=031d0cfd7c362817963f
Tested-by: syzbot+031d0cfd7c362817963f@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
[ moved clear_bit from media_devnode_release callback to media_devnode_unregister before put_device ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/media/mc/mc-devnode.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/media/mc/mc-devnode.c b/drivers/media/mc/mc-devnode.c
index 56444edaf1365..6daa7aa994422 100644
--- a/drivers/media/mc/mc-devnode.c
+++ b/drivers/media/mc/mc-devnode.c
@@ -50,11 +50,6 @@ static void media_devnode_release(struct device *cd)
 {
 	struct media_devnode *devnode = to_media_devnode(cd);
 
-	mutex_lock(&media_devnode_lock);
-	/* Mark device node number as free */
-	clear_bit(devnode->minor, media_devnode_nums);
-	mutex_unlock(&media_devnode_lock);
-
 	/* Release media_devnode and perform other cleanups as needed. */
 	if (devnode->release)
 		devnode->release(devnode);
@@ -281,6 +276,7 @@ void media_devnode_unregister(struct media_devnode *devnode)
 	/* Delete the cdev on this minor as well */
 	cdev_device_del(&devnode->cdev, &devnode->dev);
 	devnode->media_dev = NULL;
+	clear_bit(devnode->minor, media_devnode_nums);
 	mutex_unlock(&media_devnode_lock);
 
 	put_device(&devnode->dev);
-- 
2.51.0