FAILED: patch "[PATCH] media: microchip-csi2dc: fix async notifier leak on probe" failed to apply to 6.1-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 6.1-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-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x c7528789244ce7329ca883170fb9315d739ae985
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026110443-shell-unplanned-01c4@gregkh' --subject-prefix 'PATCH 6.1.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

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

From c7528789244ce7329ca883170fb9315d739ae985 Mon Sep 17 00:00:00 2001
From: Cong Nguyen <congnt264@gmail.com>
Date: Sat, 8 Aug 2026 16:07:29 +0700
Subject: [PATCH] media: microchip-csi2dc: fix async notifier leak on probe
 error path

csi2dc_of_parse() ends up calling csi2dc_prepare_notifier(), which
registers the V4L2 async notifier with v4l2_async_nf_register(). The
probe error label csi2dc_probe_cleanup_notifier is reached after
csi2dc_of_parse() has already succeeded (e.g. when media entity init,
csi2dc_power() or v4l2_async_register_subdev() fail), but it calls only
v4l2_async_nf_cleanup() and never v4l2_async_nf_unregister().

The notifier therefore stays chained in the global notifier_list while
the enclosing struct csi2dc_device is freed, leading to list corruption
and a use-after-free when the list is next walked.

Unregister the notifier before cleaning it up on the error path,
matching the teardown already done in csi2dc_remove().

Fixes: 2de0b3c0f678 ("media: atmel: introduce microchip csi2dc driver")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4
Signed-off-by: Cong Nguyen <congnt264@gmail.com>
Reviewed-by: Eugen Hristev <ehristev@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>

diff --git a/drivers/media/platform/microchip/microchip-csi2dc.c b/drivers/media/platform/microchip/microchip-csi2dc.c
index e69292f3b2a9..b2c17ff2322f 100644
--- a/drivers/media/platform/microchip/microchip-csi2dc.c
+++ b/drivers/media/platform/microchip/microchip-csi2dc.c
@@ -735,6 +735,7 @@ static int csi2dc_probe(struct platform_device *pdev)
 	return 0;
 
 csi2dc_probe_cleanup_notifier:
+	v4l2_async_nf_unregister(&csi2dc->notifier);
 	v4l2_async_nf_cleanup(&csi2dc->notifier);
 csi2dc_probe_cleanup_entity:
 	media_entity_cleanup(&csi2dc->csi2dc_sd.entity);