diff mbox series

appledisplay: fix error handling in the scheduled work

Message ID 20191106124902.7765-1-oneukum@suse.com (mailing list archive)
State Superseded
Headers show
Series appledisplay: fix error handling in the scheduled work | expand

Commit Message

Oliver Neukum Nov. 6, 2019, 12:49 p.m. UTC 
The work item can operate on

1. stale memory left over from the last transfer
the actual length of the data transfered needs to be checked
2. memory already freed
the error handling in appledisplay_probe() needs
to cancel the work in that case

Reported-and-tested-by: syzbot+495dab1f175edc9c2f13@syzkaller.appspotmail.com
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/usb/misc/appledisplay.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/usb/misc/appledisplay.c b/drivers/usb/misc/appledisplay.c
index ac92725458b5..ba1eaabc7796 100644
--- a/drivers/usb/misc/appledisplay.c
+++ b/drivers/usb/misc/appledisplay.c
@@ -164,7 +164,12 @@  static int appledisplay_bl_get_brightness(struct backlight_device *bd)
 		0,
 		pdata->msgdata, 2,
 		ACD_USB_TIMEOUT);
-	brightness = pdata->msgdata[1];
+	if (retval < 2) {
+		if (retval >= 0)
+			retval = -EMSGSIZE;
+	} else {
+		brightness = pdata->msgdata[1];
+	}
 	mutex_unlock(&pdata->sysfslock);
 
 	if (retval < 0)
@@ -299,6 +304,7 @@  static int appledisplay_probe(struct usb_interface *iface,
 	if (pdata) {
 		if (pdata->urb) {
 			usb_kill_urb(pdata->urb);
+			cancel_delayed_work_sync(&pdata->work);
 			if (pdata->urbdata)
 				usb_free_coherent(pdata->udev, ACD_URB_BUFFER_LEN,
 					pdata->urbdata, pdata->urb->transfer_dma);