[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <20231023093500.1391443-1-be286@163.com>
Date: Mon, 23 Oct 2023 17:35:00 +0800
From: Charles Yi <be286@....com>
To: jikos@...nel.org, benjamin.tissoires@...hat.com
Cc: linux-input@...r.kernel.org, linux-kernel@...r.kernel.org,
Charles Yi <be286@....com>
Subject: [PATCH] HID: fix a crash in hid_debug_events_release
hid_debug_events_release() access released memory by
hid_device_release(). This is fixed by the patch.
Signed-off-by: Charles Yi <be286@....com>
---
drivers/hid/hid-core.c | 12 ++++++++++--
drivers/hid/hid-debug.c | 3 +++
include/linux/hid.h | 3 +++
3 files changed, 16 insertions(+), 2 deletions(-)
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 8992e3c1e769..e0181218ad85 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -702,15 +702,22 @@ static void hid_close_report(struct hid_device *device)
* Free a device structure, all reports, and all fields.
*/
-static void hid_device_release(struct device *dev)
+void hiddev_free(struct kref *ref)
{
- struct hid_device *hid = to_hid_device(dev);
+ struct hid_device *hid = container_of(ref, struct hid_device, ref);
hid_close_report(hid);
kfree(hid->dev_rdesc);
kfree(hid);
}
+static void hid_device_release(struct device *dev)
+{
+ struct hid_device *hid = to_hid_device(dev);
+
+ kref_put(&hid->ref, hiddev_free);
+}
+
/*
* Fetch a report description item from the data stream. We support long
* items, though they are not used yet.
@@ -2846,6 +2853,7 @@ struct hid_device *hid_allocate_device(void)
spin_lock_init(&hdev->debug_list_lock);
sema_init(&hdev->driver_input_lock, 1);
mutex_init(&hdev->ll_open_lock);
+ kref_init(&hdev->ref);
hid_bpf_device_init(hdev);
diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c
index e7ef1ea107c9..7dd83ec74f8a 100644
--- a/drivers/hid/hid-debug.c
+++ b/drivers/hid/hid-debug.c
@@ -1135,6 +1135,7 @@ static int hid_debug_events_open(struct inode *inode, struct file *file)
goto out;
}
list->hdev = (struct hid_device *) inode->i_private;
+ kref_get(&list->hdev->ref);
file->private_data = list;
mutex_init(&list->read_mutex);
@@ -1227,6 +1228,8 @@ static int hid_debug_events_release(struct inode *inode, struct file *file)
list_del(&list->node);
spin_unlock_irqrestore(&list->hdev->debug_list_lock, flags);
kfifo_free(&list->hid_debug_fifo);
+
+ kref_put(&list->hdev->ref, hiddev_free);
kfree(list);
return 0;
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 964ca1f15e3f..3b08a2957229 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -679,6 +679,7 @@ struct hid_device { /* device report descriptor */
struct list_head debug_list;
spinlock_t debug_list_lock;
wait_queue_head_t debug_wait;
+ struct kref ref;
unsigned int id; /* system unique id */
@@ -687,6 +688,8 @@ struct hid_device { /* device report descriptor */
#endif /* CONFIG_BPF */
};
+void hiddev_free(struct kref *ref);
+
#define to_hid_device(pdev) \
container_of(pdev, struct hid_device, dev)
--
2.34.1
Powered by blists - more mailing lists