In the Linux kernel, the following vulnerability has been resolved:
usb: host: max3421: Fix shift-out-of-bounds in max3421_hub_control()
The max3421_hub_control() function handles USB hub class requests
to the virtual root hub. In the default branches of both the
ClearPortFeature and SetPortFeature switch statements, it modifies
max3421_hcd->port_status by left shifting 1 by the requests value
parameter. However, it does not validate whether this shift will exceed
the width of port_status.
So if a malicious userspace task with access to the root hub via
/dev/bus/usb/…/001 issues a USBDEVFS_CONTROL ioctl with wValue
greater than or equal to 32, the left shift operation invokes
shift-out-of-bounds undefined behavior. This results in arbitrary
bit corruption of port_status, including the normally-immutable
change bits, which can bypass internal state checks and confuse the
hub status.
Fix this by rejecting requests whose value exceeds the shift width
before performing the shift.
This issue was found using a KLEE-based symbolic execution tool for kernel drivers that Im currently developing.
References
- https://git.kernel.org/stable/c/00dd025324b56d39d37e57a08f473dab3a660f30
- https://git.kernel.org/stable/c/02d03c61e8a7b016956acb48e8a2512d16d87517
- https://git.kernel.org/stable/c/08b1d4cab0230697bc74c63fc4e40170a7559c54
- https://git.kernel.org/stable/c/3be5f24e8270ba53b3c814d13689bb8644c86237
- https://git.kernel.org/stable/c/4da073d57176d8e1c2bca34febfbc81d2560c1a5
- https://git.kernel.org/stable/c/cff06b03b530ae1fe8a13e93a7848f2130e00fb4
- https://git.kernel.org/stable/c/d512bdefd241b98f4d7bcb5bab5614a86411fad4
- https://git.kernel.org/stable/c/e5fa9d8f40746ec3447335c9642c03410f5fd3af