CVE-2024-27001

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 vmk80xxfindusbendpoints() 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 'panicon_warn' set on them.

Fix the issue found by Syzkaller [1] by somewhat simplifying the endpoint checking process with usbfindcommon_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 usbsubmiturb+0xc4e/0x18c0 drivers/usb/core/urb.c:503 ... Call Trace: <TASK> usbstartwaiturb+0x113/0x520 drivers/usb/core/message.c:59 vmk80xxresetdevice drivers/comedi/drivers/vmk80xx.c:227 [inline] vmk80xxautoattach+0xa1c/0x1a40 drivers/comedi/drivers/vmk80xx.c:818 comediautoconfig+0x238/0x380 drivers/comedi/drivers.c:1067 usbprobe_interface+0x5cd/0xb00 drivers/usb/core/driver.c:399 ...

Similar issue also found by Syzkaller: