As syzkaller spotted, currently caiaq driver submits a URB with the fixed EP without checking whether it's actually available, which may result in a kernel warning like: usb 1-1: BOGUS urb xfer, pipe 3 != type 1 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 1150 at drivers/usb/core/urb.c:449 usb_submit_urb+0xf8a/0x11d0 Modules linked in: CPU: 1 PID: 1150 Comm: kworker/1:1 Not tainted 4.14.0-rc2-42660-g24b7bd59eec0 #277 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: init_card sound/usb/caiaq/device.c:467 snd_probe+0x81c/0x1150 sound/usb/caiaq/device.c:525 usb_probe_interface+0x35d/0x8e0 drivers/usb/core/driver.c:361 ....
This patch adds a sanity check of validity of EPs at the device initialization phase for avoiding the call with an invalid EP.
Reported-by: Andrey Konovalov andreyknvl@google.com Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/usb/caiaq/device.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/sound/usb/caiaq/device.c b/sound/usb/caiaq/device.c index 0fb6b1b79261..a29674bf96e5 100644 --- a/sound/usb/caiaq/device.c +++ b/sound/usb/caiaq/device.c @@ -461,6 +461,13 @@ static int init_card(struct snd_usb_caiaqdev *cdev) cdev->midi_out_buf, EP1_BUFSIZE, snd_usb_caiaq_midi_output_done, cdev);
+ /* sanity checks of EPs before actually submitting */ + if (usb_urb_ep_type_check(&cdev->ep1_in_urb) || + usb_urb_ep_type_check(&cdev->midi_out_urb)) { + dev_err(dev, "invalid EPs\n"); + return -EINVAL; + } + init_waitqueue_head(&cdev->ep1_wait_queue); init_waitqueue_head(&cdev->prepare_wait_queue);