FAILED: patch "[PATCH] Input: ims-pcu - fix race condition in reset_device sysfs" failed to apply to 5.15-stable tree

The patch below does not apply to the 5.15-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 <[email protected]>.

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-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 411b8c4b274737c3bf08e1e025801161603cfffc
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026072030-handwork-earmuff-b1c2@gregkh' --subject-prefix 'PATCH 5.15.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

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

From 411b8c4b274737c3bf08e1e025801161603cfffc Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <[email protected]>
Date: Fri, 22 May 2026 10:29:04 -0700
Subject: [PATCH] Input: ims-pcu - fix race condition in reset_device sysfs
callback

The ims_pcu_reset_device() sysfs callback calls ims_pcu_execute_command() without acquiring pcu->cmd_mutex. This can lead to data races and corruption of the shared command buffer if triggered concurrently with other commands.

Acquire pcu->cmd_mutex before calling ims_pcu_execute_command().

index 4f8265c0772f..39bc02ef3e53 100644
@@ -1153,6 +1153,8 @@ static ssize_t ims_pcu_reset_device(struct device *dev,
 
 	dev_info(pcu->dev, "Attempting to reset device\n");
 
+	guard(mutex)(&pcu->cmd_mutex);
+
 	error = ims_pcu_execute_command(pcu, PCU_RESET, &reset_byte, 1);
 	if (error) {
 		dev_info(pcu->dev,

From: Dmitry Torokhov <[email protected]>

[ Upstream commit 411b8c4b274737c3bf08e1e025801161603cfffc ]

The ims_pcu_reset_device() sysfs callback calls ims_pcu_execute_command() without acquiring pcu->cmd_mutex. This can lead to data races and corruption of the shared command buffer if triggered concurrently with other commands.

Acquire pcu->cmd_mutex before calling ims_pcu_execute_command().

---
 drivers/input/misc/ims-pcu.c | 2 ++
 1 file changed, 2 insertions(+)

index 59055818e0e6fc..ffb478cca604d6 100644
@@ -1173,6 +1173,8 @@ static ssize_t ims_pcu_reset_device(struct device *dev,
 
 	dev_info(pcu->dev, "Attempting to reset device\n");
 
+	guard(mutex)(&pcu->cmd_mutex);
+
 	error = ims_pcu_execute_command(pcu, PCU_RESET, &reset_byte, 1);
 	if (error) {
 		dev_info(pcu->dev,

2.53.0