comedi: vmk80xx: fix incomplete endpoint checking

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: comedi: vmk80xx: fix incomplete endpoint checking While vmk80xx does have endpoint checking implemented, some things can fall through the cracks. Depending on the hardware model, URBs can have either bulk or interrupt type, and current version of vmk80xx_find_usb_endpoints() function does not take that fully into account. While this warning does not seem to be too harmful, at the very least it will crash systems with 'panic_on_warn' set on them. Fix the issue found by Syzkaller [1] by somewhat simplifying the endpoint checking process with usb_find_common_endpoints() and ensuring that only expected endpoint types are present. This patch has not been tested on real hardware. [1] Syzkaller report: usb 1-1: BOGUS urb xfer, pipe 1 != type 3 WARNING: CPU: 0 PID: 781 at drivers/usb/core/urb.c:504 usb_submit_urb+0xc4e/0x18c0 drivers/usb/core/urb.c:503 ... Call Trace: <TASK> usb_start_wait_urb+0x113/0x520 drivers/usb/core/message.c:59 vmk80xx_reset_device drivers/comedi/drivers/vmk80xx.c:227 [inline] vmk80xx_auto_attach+0xa1c/0x1a40 drivers/comedi/drivers/vmk80xx.c:818 comedi_auto_config+0x238/0x380 drivers/comedi/drivers.c:1067 usb_probe_interface+0x5cd/0xb00 drivers/usb/core/driver.c:399 ... Similar issue also found by Syzkaller:

References

• https://git.kernel.org/stable/c/3a63ae0348d990e137cca04eced5b08379969ea9
• https://git.kernel.org/stable/c/a3b8ae7e9297dd453f2977b011c5bc75eb20e71b
• https://git.kernel.org/stable/c/f15370e315976198f338b41611f37ce82af6cf54
• https://git.kernel.org/stable/c/b0b268eeb087e324ef3ea71f8e6cabd07630517f
• https://git.kernel.org/stable/c/ac882d6b21bffecb57bcc4486701239eef5aa67b
• https://git.kernel.org/stable/c/59f33af9796160f851641d960bd93937f282c696
• https://git.kernel.org/stable/c/6ec3514a7d35ad9cfab600187612c29f669069d2
• https://git.kernel.org/stable/c/d1718530e3f640b7d5f0050e725216eab57a85d8