FAILED: patch "[PATCH] power: supply: bq24257: fix use-after-free on remove" failed to apply to 5.10-stable tree

PATCH New [email protected] 2 participants 3 messages Sep 3 – Sep 9

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Stable branch Power supply

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[email protected]

author maintainer

2026-09-03 15:35 UTC #0 lore raw

The patch below does not apply to the 5.10-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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 9d34c9d660c3d0931d2cc749c46c47cf31f96e48
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026090327-map-reptilian-66d3@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

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

From 9d34c9d660c3d0931d2cc749c46c47cf31f96e48 Mon Sep 17 00:00:00 2001
From: Fan Wu <[email protected]>
Date: Sat, 1 Aug 2026 05:19:58 +0000
Subject: [PATCH] power: supply: bq24257: fix use-after-free on remove

The STAT-pin interrupt is devm-managed, so it stays armed until the devm cleanup that runs after remove() returns. remove() cancels bq->iilimit_setup_work while the threaded handler can still fire; that handler reschedules the work and dereferences bq, so the work runs against freed memory once devm frees bq.

Make the delayed work device-managed with devm_delayed_work_autocancel(), registered before the interrupt request. The devm cleanup then releases the interrupt first, so the handler can no longer reschedule the work, and cancels the work before bq is freed. The explicit cancel_delayed_work_sync() in remove() is no longer needed and is dropped.

Found by static analysis.

Fixes 2219a935963e ("power_supply: Add TI BQ24257 charger driver")

Cc [email protected]

Assisted-by Codex:gpt-5.6

Signed-off-by Fan Wu <[email protected]>

Link https://patch.msgid.link/[email protected] open here

Signed-off-by Sebastian Reichel <[email protected]>

drivers/power/supply/bq24257_charger.c +9 -7

index d6286be4af74..944a7aa6f187 100644
@@ -18,6 +18,7 @@
 #include <linux/gpio/consumer.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
+#include <linux/devm-helpers.h>
 
 #include <linux/acpi.h>
 #include <linux/of.h>

@@ -1003,10 +1004,6 @@ static int bq24257_probe(struct i2c_client *client)
 	if (bq->info->chip == BQ24250)
 		bq->iilimit_autoset_enable = false;
 
-	if (bq->iilimit_autoset_enable)
-		INIT_DELAYED_WORK(&bq->iilimit_setup_work,
-				  bq24257_iilimit_setup_work);
-
 	/*
 	 * The BQ24250 doesn't have a dedicated Power Good (PG) pin so let's
 	 * not probe for it and instead use a SW-based approach to determine

@@ -1047,6 +1044,14 @@ static int bq24257_probe(struct i2c_client *client)
 		return ret;
 	}
 
+	if (bq->iilimit_autoset_enable) {
+		ret = devm_delayed_work_autocancel(dev,
+						   &bq->iilimit_setup_work,
+						   bq24257_iilimit_setup_work);
+		if (ret)
+			return ret;
+	}
+
 	ret = devm_request_threaded_irq(dev, client->irq, NULL,
 					bq24257_irq_handler_thread,
 					IRQF_TRIGGER_FALLING |

@@ -1062,9 +1067,6 @@ static void bq24257_remove(struct i2c_client *client)
 {
 	struct bq24257_device *bq = i2c_get_clientdata(client);
 
-	if (bq->iilimit_autoset_enable)
-		cancel_delayed_work_sync(&bq->iilimit_setup_work);
-
 	bq24257_field_write(bq, F_RESET, 1); /* reset to defaults */
 }

Sasha Levin

maintainer

2026-09-09 16:57 UTC #1 lore raw

PATCH 1/2 workqueue: Add resource managed version of delayed work init

From: Matti Vaittinen <[email protected]>

[ Upstream commit 0341ce5443949588e93581b49b934cdde2befbf8 ]

A few drivers which need a delayed work-queue must cancel work at driver detach. Some of those implement remove() solely for this purpose. Help drivers to avoid unnecessary remove and error-branch implementation by adding managed verision of delayed work initialization. This will also help drivers to avoid mixing manual and devm based unwinding when other resources are handled by devm.

Reviewed-by Hans de Goede <[email protected]>

Signed-off-by Matti Vaittinen <[email protected]>

Link https://lore.kernel.org/r/51769ea4668198deb798fe47fcfb5f5288d61586.1616506559.git.matti.vaittinen@fi.rohmeurope.com open here

Signed-off-by Greg Kroah-Hartman <[email protected]>

Stable-dep-of: 9d34c9d660c3 ("power: supply: bq24257: fix use-after-free on remove")

Signed-off-by Sasha Levin <[email protected]>

---
 include/linux/devm-helpers.h | 53 ++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)
 create mode 100644 include/linux/devm-helpers.h

include/linux/devm-helpers.h new file +53 -0

new file mode 100644
index 0000000000000..f64e0c9f3763c
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __LINUX_DEVM_HELPERS_H
+#define __LINUX_DEVM_HELPERS_H
+
+/*
+ * Functions which do automatically cancel operations or release resources upon
+ * driver detach.
+ *
+ * These should be helpful to avoid mixing the manual and devm-based resource
+ * management which can be source of annoying, rarely occurring,
+ * hard-to-reproduce bugs.
+ *
+ * Please take into account that devm based cancellation may be performed some
+ * time after the remove() is ran.
+ *
+ * Thus mixing devm and manual resource management can easily cause problems
+ * when unwinding operations with dependencies. IRQ scheduling a work in a queue
+ * is typical example where IRQs are often devm-managed and WQs are manually
+ * cleaned at remove(). If IRQs are not manually freed at remove() (and this is
+ * often the case when we use devm for IRQs) we have a period of time after
+ * remove() - and before devm managed IRQs are freed - where new IRQ may fire
+ * and schedule a work item which won't be cancelled because remove() was
+ * already ran.
+ */
+
+#include <linux/device.h>
+#include <linux/workqueue.h>
+
+static inline void devm_delayed_work_drop(void *res)
+{
+	cancel_delayed_work_sync(res);
+}
+
+/**
+ * devm_delayed_work_autocancel - Resource-managed work allocation
+ * @dev: Device which lifetime work is bound to
+ * @pdata: work to be cancelled when driver is detached
+ *
+ * Initialize work which is automatically cancelled when driver is detached.
+ * A few drivers need delayed work which must be cancelled before driver
+ * is detached to avoid accessing removed resources.
+ * devm_delayed_work_autocancel() can be used to omit the explicit
+ * cancelleation when driver is detached.
+ */
+static inline int devm_delayed_work_autocancel(struct device *dev,
+					       struct delayed_work *w,
+					       work_func_t worker)
+{
+	INIT_DELAYED_WORK(w, worker);
+	return devm_add_action(dev, devm_delayed_work_drop, w);
+}
+
+#endif

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2.53.0