Re: [syzbot] [media?] [usb?] KASAN: slab-use-after-free Read in v4l2_open

[Edward Adam Davis]

#syz test

diff --git a/drivers/media/usb/em28xx/em28xx-video.c b/drivers/media/usb/em28xx/em28xx-video.c
index b0c184f237a7..563b4267588e 100644
--- a/drivers/media/usb/em28xx/em28xx-video.c
+++ b/drivers/media/usb/em28xx/em28xx-video.c
@@ -2147,7 +2147,7 @@ static int em28xx_v4l2_open(struct file *filp)
 			video_device_node_name(vdev), v4l2_type_names[fh_type],
 			v4l2->users);
 
-	if (mutex_lock_interruptible(&dev->lock))
+	if (!mutex_trylock(&dev->lock))
 		return -ERESTARTSYS;
 
 	ret = v4l2_fh_open(filp);