CVE-2022-49884 Information

Description

In the Linux kernel the following vulnerability has been resolved:

KVM: Initialize gfn_to_pfn_cache locks in dedicated helper

Move the gfn_to_pfn_cache lock initialization to another helper and call the new helper during VM/vCPU creation. There are race conditions possible due to kvm_gfn_to_pfn_cache_init()’s ability to re-initialize the cache’s locks.

For example: a race between ioctl(KVM_XEN_HVM_EVTCHN_SEND) and kvm_gfn_to_pfn_cache_init() leads to a corrupted shinfo gpc lock.

            (thread 1)                |           (thread 2)
                                      |

kvm_xen_set_evtchn_fast | read_lock_irqsave(&gpc->lock …) | | kvm_gfn_to_pfn_cache_init | rwlock_init(&gpc->lock) read_unlock_irqrestore(&gpc->lock …) |

Rename ## Reference https://git.kernel.org/stable/c/52491a38b2c2411f3f0229dc6ad610349c704a41 https://git.kernel.org/stable/c/61242001d6c9c253df7645dab090842d8da08764