diff mbox series

HID: wacom: fix memory leak on size mismatch in wacom_wac_queue_flush()

Message ID 20250329002042.36967-1-qasdev00@gmail.com (mailing list archive)
State New
Delegated to: Jiri Kosina
Headers show
Series HID: wacom: fix memory leak on size mismatch in wacom_wac_queue_flush() | expand

Commit Message

Qasim Ijaz March 29, 2025, 12:20 a.m. UTC
In wacom_wac_queue_flush() the code allocates zero initialised 
buffer which it uses as a storage buffer for copying data from 
a fifo via kfifo_out(). The kfifo_out() function returns the 
number of elements it has copied. The code checks if the number 
of copied elements does not equal the size of the fifo record, 
if it does not it simply skips the entry and continues to the
next iteration. However it does not release the storage buffer 
leading to a memory leak.
 
Fix the memory leak by freeing the buffer on size mismatch.

Fixes: 5e013ad20689 ("HID: wacom: Remove static WACOM_PKGLEN_MAX limit")
Signed-off-by: Qasim Ijaz <qasdev00@gmail.com>
---
 drivers/hid/wacom_sys.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Markus Elfring March 29, 2025, 12:04 p.m. UTC | #1
> number of elements it has copied. The code checks if the number
> of copied elements does not equal the size of the fifo record,
…
                     is?

Under which circumstances would you dare to use text lines
which would be longer than 63 characters?


Can a patch series be more appropriate for the affected software module?

Regards,
Markus
diff mbox series

Patch

diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index 666b7eb0fdfe..3e4f823f8ee8 100644
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -87,6 +87,7 @@  static void wacom_wac_queue_flush(struct hid_device *hdev,
 			// to flush seems reasonable enough, however.
 			hid_warn(hdev, "%s: removed fifo entry with unexpected size\n",
 				 __func__);
+			kfree(buf);
 			continue;
 		}
 		err = hid_report_raw_event(hdev, HID_INPUT_REPORT, buf, size, false);