From: Pietro Borrello <borrello@xxxxxxxxxxxxxxxx>
[ Upstream commit 76ca8da989c7d97a7f76c75d475fe95a584439d7 ]
Use spinlocks to deal with workers introducing a wrapper
bigben_schedule_work(), and several spinlock checks.
Otherwise, bigben_set_led() may schedule bigben->worker after the
structure has been freed, causing a use-after-free.
Fixes: 4eb1b01de5b9 ("HID: hid-bigbenff: fix race condition for scheduled work during removal")
Signed-off-by: Pietro Borrello <borrello@xxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230125-hid-unregister-leds-v4-3-7860c5763c38@xxxxxxxxxxxxxxxx
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/hid/hid-bigbenff.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/drivers/hid/hid-bigbenff.c b/drivers/hid/hid-bigbenff.c
index b98c5f31c184b..9d6560db762b1 100644
--- a/drivers/hid/hid-bigbenff.c
+++ b/drivers/hid/hid-bigbenff.c
@@ -185,6 +185,15 @@ struct bigben_device {
struct work_struct worker;
};
+static inline void bigben_schedule_work(struct bigben_device *bigben)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&bigben->lock, flags);
+ if (!bigben->removed)
+ schedule_work(&bigben->worker);
+ spin_unlock_irqrestore(&bigben->lock, flags);
+}
static void bigben_worker(struct work_struct *work)
{
@@ -197,9 +206,6 @@ static void bigben_worker(struct work_struct *work)
u32 len;
unsigned long flags;
- if (bigben->removed)
- return;
-
buf = hid_alloc_report_buf(bigben->report, GFP_KERNEL);
if (!buf)
return;
@@ -285,7 +291,7 @@ static int hid_bigben_play_effect(struct input_dev *dev, void *data,
bigben->work_ff = true;
spin_unlock_irqrestore(&bigben->lock, flags);
- schedule_work(&bigben->worker);
+ bigben_schedule_work(bigben);
}
return 0;
@@ -320,7 +326,7 @@ static void bigben_set_led(struct led_classdev *led,
if (work) {
bigben->work_led = true;
- schedule_work(&bigben->worker);
+ bigben_schedule_work(bigben);
}
return;
}
@@ -450,7 +456,7 @@ static int bigben_probe(struct hid_device *hid,
bigben->left_motor_force = 0;
bigben->work_led = true;
bigben->work_ff = true;
- schedule_work(&bigben->worker);
+ bigben_schedule_work(bigben);
hid_info(hid, "LED and force feedback support for BigBen gamepad\n");
--
2.39.2
