HID: hidraw: Add spinlock in struct hidraw to protect list
It is unsafe to call list_for_each_entry in hidraw_report_event to
traverse each hidraw_list node without a lock protection, the list
could be modified if someone calls hidraw_release and list_del to
remove itself from the list, this can cause hidraw_report_event
to touch a deleted list struct and panic.
To prevent this, introduce a spinlock in struct hidraw to protect
list from concurrent access.
Signed-off-by: Yonghua Zheng <younghua.zheng@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/include/linux/hidraw.h b/include/linux/hidraw.h
index 2451662..ddf5261 100644
--- a/include/linux/hidraw.h
+++ b/include/linux/hidraw.h
@@ -23,6 +23,7 @@
wait_queue_head_t wait;
struct hid_device *hid;
struct device *dev;
+ spinlock_t list_lock;
struct list_head list;
};