Hi On 5/3/24 08:58, Mauro Carvalho Chehab wrote: > Em Tue, 9 Apr 2024 07:36:34 -0700 > Nikita Zhandarovich <n.zhandarovich@xxxxxxxxxx> escreveu: > >> Syzkaller reported a warning [1] in smsusb_submit_urb() which occurs >> if an attempt is made to send a bulk URB using the wrong endpoint >> type. The current approach to perform endpoint checking does not >> explicitly check if an endpoint in question has its type set to bulk. >> >> Fix this issue by using functions usb_endpoint_is_bulk_XXX() to >> enable testing for correct ep types. >> >> This patch has not been tested on real hardware. >> >> [1] Syzkaller report: >> usb 1-1: string descriptor 0 read error: -71 >> smsusb:smsusb_probe: board id=2, interface number 0 >> smsusb:siano_media_device_register: media controller created >> ------------[ cut here ]------------ >> usb 1-1: BOGUS urb xfer, pipe 3 != type 1 >> WARNING: CPU: 0 PID: 3147 at drivers/usb/core/urb.c:494 usb_submit_urb+0xacd/0x1550 drivers/usb/core/urb.c:493 >> ... >> Call Trace: >> smsusb_start_streaming+0x16/0x1d0 drivers/media/usb/siano/smsusb.c:195 >> smsusb_init_device+0xd85/0x12d0 drivers/media/usb/siano/smsusb.c:475 >> smsusb_probe+0x496/0xa90 drivers/media/usb/siano/smsusb.c:566 >> usb_probe_interface+0x633/0xb40 drivers/usb/core/driver.c:396 >> really_probe+0x3cb/0x1020 drivers/base/dd.c:580 >> driver_probe_device+0x178/0x350 drivers/base/dd.c:763 >> ... >> hub_event+0x48d/0xd90 drivers/usb/core/hub.c:5644 >> process_one_work+0x833/0x10c0 kernel/workqueue.c:2276 >> worker_thread+0xac1/0x1300 kernel/workqueue.c:2422 >> kthread+0x39a/0x3c0 kernel/kthread.c:313 >> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 >> >> Reported-and-tested-by: syzbot+12002a39b8c60510f8fb@xxxxxxxxxxxxxxxxxxxxxxxxx >> Fixes: 31e0456de5be ("media: usb: siano: Fix general protection fault in smsusb") >> Signed-off-by: Nikita Zhandarovich <n.zhandarovich@xxxxxxxxxx> >> --- >> drivers/media/usb/siano/smsusb.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/media/usb/siano/smsusb.c b/drivers/media/usb/siano/smsusb.c >> index 723510520d09..daaac121c670 100644 >> --- a/drivers/media/usb/siano/smsusb.c >> +++ b/drivers/media/usb/siano/smsusb.c >> @@ -405,10 +405,10 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id) >> struct usb_endpoint_descriptor *desc = >> &intf->cur_altsetting->endpoint[i].desc; >> >> - if (desc->bEndpointAddress & USB_DIR_IN) { >> + if (usb_endpoint_is_bulk_in(desc)) { >> dev->in_ep = desc->bEndpointAddress; >> align = usb_endpoint_maxp(desc) - sizeof(struct sms_msg_hdr); >> - } else { >> + } else if (usb_endpoint_is_bulk_out(desc)) { > > Did you test it on what devices? I'm not sure if all siano devices > are bulk. Why did you decide to use usb_endpoint_is_bulk_(in|out) > instead of usb_endpoint_dir_(in|out)? I did not have the hardware required to test it properly, I'm afraid. I made sure to point that out in the patch description. As for siano devices possibly having different endpoints type apart from bulk, I was relying on the rest of the driver code to determine just that (which is maybe somewhat flawed in this case). Since smsusb_submit_urb() (and some other functions like usb_rcvbulkpipe()) works exclusively with bulk types, I did not feel the need to even expect int types, for instance. > > Regards, > Mauro > >> dev->out_ep = desc->bEndpointAddress; >> } >> } >> With regards, Nikita