On Sun, 29 Dec 2019, syzbot wrote: > syzbot has found a reproducer for the following crash on: > > HEAD commit: ecdf2214 usb: gadget: add raw-gadget interface > git tree: https://github.com/google/kasan.git usb-fuzzer > console output: https://syzkaller.appspot.com/x/log.txt?x=17416885e00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=b06a019075333661 > dashboard link: https://syzkaller.appspot.com/bug?extid=10e5f68920f13587ab12 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13598885e00000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+10e5f68920f13587ab12@xxxxxxxxxxxxxxxxxxxxxxxxx > > ------------[ cut here ]------------ > usb 1-1: BOGUS urb xfer, pipe 2 != type 2 > WARNING: CPU: 0 PID: 2388 at drivers/usb/core/urb.c:478 > usb_submit_urb+0x1188/0x13b0 drivers/usb/core/urb.c:478 That's a strange diagnostic. Let's see what's really going on. Alan Stern #syz test: https://github.com/google/kasan.git ecdf2214 Index: usb-devel/drivers/usb/core/urb.c =================================================================== --- usb-devel.orig/drivers/usb/core/urb.c +++ usb-devel/drivers/usb/core/urb.c @@ -204,10 +204,14 @@ int usb_urb_ep_type_check(const struct u const struct usb_host_endpoint *ep; ep = usb_pipe_endpoint(urb->dev, urb->pipe); - if (!ep) + if (!ep) { + dev_info(&urb->dev->dev, "Pipe 0x%x, no ep\n", urb->pipe); return -EINVAL; - if (usb_pipetype(urb->pipe) != pipetypes[usb_endpoint_type(&ep->desc)]) + } + if (usb_pipetype(urb->pipe) != pipetypes[usb_endpoint_type(&ep->desc)]) { + dev_info(&urb->dev->dev, "Pipe/ep type mismatch\n"); return -EINVAL; + } return 0; } EXPORT_SYMBOL_GPL(usb_urb_ep_type_check);
