Commit e1ca5f39 authored by Qasim Ijaz's avatar Qasim Ijaz Committed by Jiri Kosina
Browse files

HID: wacom: handle kzalloc() allocation failure in wacom_wac_queue_flush() 



During wacom_wac_queue_flush() the code calls
kzalloc() to allocate a zero initialised buffer
which it uses as a storage buffer to get data
from the fifo via kfifo_out(). However it does not
check kzalloc() for allocation failure which returns
NULL and could potentially lead to a NULL deref.

Fix this by checking for kzalloc() failure and skipping
the current entry if allocation failure occurs.

Fixes: 5e013ad2 ("HID: wacom: Remove static WACOM_PKGLEN_MAX limit")
Signed-off-by: default avatarQasim Ijaz <qasdev00@gmail.com>
Reviewed-by: default avatarJason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.com>
parent 09d54630

drivers/hid/wacom_sys.c

+7 −1
Original line number Diff line number Diff line
@@ -70,10 +70,16 @@ static void wacom_wac_queue_flush(struct hid_device *hdev, 
{

	while (!kfifo_is_empty(fifo)) {

		int size = kfifo_peek_len(fifo);

		u8 *buf = kzalloc(size, GFP_KERNEL);

		u8 *buf;

		unsigned int count;

		int err;



		buf = kzalloc(size, GFP_KERNEL);

		if (!buf) {

			kfifo_skip(fifo);

			continue;

		}



		count = kfifo_out(fifo, buf, size);

		if (count != size) {

			// Hard to say what is the "right" action in this