CVE-2022-50470

In the Linux kernel, the following vulnerability has been resolved:

xhci: Remove device endpoints from bandwidth list when freeing the device

Endpoints are normally deleted from the bandwidth list when they are dropped, before the virt device is freed.

If xHC host is dying or being removed then the endpoints arent dropped cleanly due to functions returning early to avoid interacting with a non-accessible host controller.

So check and delete endpoints that are still on the bandwidth list when freeing the virt device.

Solves a list_del corruption kernel crash when unbinding xhci-pci, caused by xhci_mem_cleanup() when it later tried to delete already freed endpoints from the bandwidth list.

This only affects hosts that use software bandwidth checking, which currenty is only the xHC in intel Panther Point PCH (Ivy Bridge)

Affected Software

References

• https://git.kernel.org/stable/c/3bf860a41e0f2fcea0ac3aae8f7ef887a7994b70
• https://git.kernel.org/stable/c/5aed5b7c2430ce318a8e62f752f181e66f0d1053
• https://git.kernel.org/stable/c/5e4ce28ad907aa54f13b21d5f1dc490525957b0c
• https://git.kernel.org/stable/c/678d2cc2041cc6ce05030852dce9ad42719abcfc
• https://git.kernel.org/stable/c/8f1cd9633d1f21efc13e8fc75be8f2b6bb85e38c
• https://git.kernel.org/stable/c/c892a81c7424b4f6a660cb9c249d354ccf3afeca
• https://git.kernel.org/stable/c/cebbc8d335d6bcc1316584f779c08f80287c6af8
• https://git.kernel.org/stable/c/f0de39474078adef6ece7a183e34c15ce2c1d8d1