CVE-2022-49882
published 2025-05-01CVE-2022-49882: In the Linux kernel, the following vulnerability has been resolved: KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache Reject kvm_gpc_check()…
PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.18%
7.6th percentile
In the Linux kernel, the following vulnerability has been resolved:
KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache
Reject kvm_gpc_check() and kvm_gpc_refresh() if the cache is inactive.
Not checking the active flag during refresh is particularly egregious, as
KVM can end up with a valid, inactive cache, which can lead to a variety
of use-after-free bugs, e.g. consuming a NULL kernel pointer or missing
an mmu_notifier invalidation due to the cache not being on the list of
gfns to invalidate.
Note, "active" needs to be set if and only if the cache is on the list
of caches, i.e. is reachable via mmu_notifier events. If a relevant
mmu_notifier event occurs while the cache is "active" but not on the
list, KVM will not acquire the cache's lock and so will not serailize
the mmu_notifier event with active users and/or kvm_gpc_refresh().
A race between KVM_XEN_ATTR_TYPE_SHARED_INFO and KVM_XEN_HVM_EVTCHN_SEND
can be exploited to trigger the bug.
1. Deactivate shinfo cache:
kvm_xen_hvm_set_attr
case KVM_XEN_ATTR_TYPE_SHARED_INFO
kvm_gpc_deactivate
kvm_gpc_unmap
gpc->valid = false
gpc->khva = NULL
gpc->active = false
Result: active = false, valid = false
2. Cause cache refresh:
kvm_arch_vm_ioctl
case KVM_XEN_HVM_EVTCHN_SEND
kvm_xen_hvm_evtchn_send
kvm_xen_set_evtchn
kvm_xen_set_evtchn_fast
kvm_gpc_check
return -EWOULDBLOCK because !gpc->valid
kvm_xen_set_evtchn_fast
return -EWOULDBLOCK
kvm_gpc_refresh
hva_to_pfn_retry
gpc->valid = true
gpc->khva = not NULL
Result: active = false, valid = true
3. Race ioctl KVM_XEN_HVM_EVTCHN_SEND against ioctl
KVM_XEN_ATTR_TYPE_SHARED_INFO:
kvm_arch_vm_ioctl
case KVM_XEN_HVM_EVTCHN_SEND
kvm_xen_hvm_evtchn_send
kvm_xen_set_evtchn
kvm_xen_set_evtchn_fast
read_lock gpc->lock
kvm_xen_hvm_set_attr case
KVM_XEN_ATTR_TYPE_SHARED_INFO
mutex_lock kvm->lock
kvm_xen_shared_info_init
kvm_gpc_activate
gpc->khva = NULL
kvm_gpc_check
[ Check passes because gpc->valid is
still true, even though gpc->khva
is already NULL. ]
sh
Affected
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.0.8-1 (bookworm) | linux 6.0.8-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 982ed0de4753ed6e71dbd40f82a5a066baf133ed < bfa9672f8fc9eb118124bab61899d2dd497f95ba | bfa9672f8fc9eb118124bab61899d2dd497f95ba |
| linux | linux | >= 982ed0de4753ed6e71dbd40f82a5a066baf133ed < ecbcf030b45666ad11bc98565e71dfbcb7be4393 | ecbcf030b45666ad11bc98565e71dfbcb7be4393 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.0.8-1 | 6.0.8-1 |
| linux | linux_kernel | >= 0 < 6.0.8-1 | 6.0.8-1 |
| linux | linux_kernel | >= 0 < 6.0.8-1 | 6.0.8-1 |
| linux | linux_kernel | >= 5.17 < 6.0.8 | 6.0.8 |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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GHSA
GHSA-crgv-wqmc-m2wr: In the Linux kernel, the following vulnerability has been resolved:
KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache
Reject kvm_
ghsa_unreviewed·2025-05-01
CVE-2022-49882 [HIGH] CWE-416 GHSA-crgv-wqmc-m2wr: In the Linux kernel, the following vulnerability has been resolved:
KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache
Reject kvm_
In the Linux kernel, the following vulnerability has been resolved:
KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache
Reject kvm_gpc_check() and kvm_gpc_refresh() if the cache is inactive.
Not checking the active flag during refresh is particularly egregious, as
KVM can end up with a valid, inactive cache, which can lead to a variety
of use-after-free bugs, e.g. consuming a NULL kernel pointer or missing
an mmu_notifier invalidation due to the cache not being on the list of
gfns to invalidate.
Note, "active" needs to be set if and only if the cache is on the list
of caches, i.e. is reachable via mmu_notifier events. If a relevant
mmu_notifier event occurs while the cache is "active" but not on the
list, KVM will not acquire the cache's lock and so will not serailize
t
OSV
CVE-2022-49882: In the Linux kernel, the following vulnerability has been resolved: KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache Reject kvm_gp
osv·2025-05-01·CVSS 7.8
CVE-2022-49882 [HIGH] CVE-2022-49882: In the Linux kernel, the following vulnerability has been resolved: KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache Reject kvm_gp
In the Linux kernel, the following vulnerability has been resolved: KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache Reject kvm_gpc_check() and kvm_gpc_refresh() if the cache is inactive. Not checking the active flag during refresh is particularly egregious, as KVM can end up with a valid, inactive cache, which can lead to a variety of use-after-free bugs, e.g. consuming a NULL kernel pointer or missing an mmu_notifier invalidation due to the cache not being on the list of gfns to invalidate. Note, "active" needs to be set if and only if the cache is on the list of caches, i.e. is reachable via mmu_notifier events. If a relevant mmu_notifier event occurs while the cache is "active" but not on the list, KVM will not acquire the cache's lock and so will not serailize the
Red Hat
kernel: KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache
vendor_redhat·2025-05-01·CVSS 7.8
CVE-2022-49882 [HIGH] kernel: KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache
kernel: KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache
In the Linux kernel, the following vulnerability has been resolved:
KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache
Reject kvm_gpc_check() and kvm_gpc_refresh() if the cache is inactive.
Not checking the active flag during refresh is particularly egregious, as
KVM can end up with a valid, inactive cache, which can lead to a variety
of use-after-free bugs, e.g. consuming a NULL kernel pointer or missing
an mmu_notifier invalidation due to the cache not being on the list of
gfns to invalidate.
Note, "active" needs to be set if and only if the cache is on the list
of caches, i.e. is reachable via mmu_notifier events. If a relevant
mmu_notifier event occurs while the cache is "active" but not on
Debian
CVE-2022-49882: linux - In the Linux kernel, the following vulnerability has been resolved: KVM: Reject...
vendor_debian·2022·CVSS 7.8
CVE-2022-49882 [HIGH] CVE-2022-49882: linux - In the Linux kernel, the following vulnerability has been resolved: KVM: Reject...
In the Linux kernel, the following vulnerability has been resolved: KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache Reject kvm_gpc_check() and kvm_gpc_refresh() if the cache is inactive. Not checking the active flag during refresh is particularly egregious, as KVM can end up with a valid, inactive cache, which can lead to a variety of use-after-free bugs, e.g. consuming a NULL kernel pointer or missing an mmu_notifier invalidation due to the cache not being on the list of gfns to invalidate. Note, "active" needs to be set if and only if the cache is on the list of caches, i.e. is reachable via mmu_notifier events. If a relevant mmu_notifier event occurs while the cache is "active" but not on the list, KVM will not acquire the cache's lock and so will not serailize the
No detection rules found.
No public exploits indexed.
2025-05-01
Published