CVE-2022-49610 KVM: VMX: Prevent RSB underflow before vmenter

In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Prevent RSB underflow before vmenter On VMX, there are some balanced returns between the time the guest's SPECCTRL value is written, and the vmenter. Balanced returns matched by a preceding call are usually ok, but it's...

CVE-2022-49610

The CVE-2022-49610 entry concerns the Linux kernel KVM VMX path. The vulnerability description states a theoretical RSB underflow could occur on VMX when there is a gap between the guest SPEC_CTRL write and vmenter, potentially triggered by an NMI with a deep call stack. The mitigation is to disa...

CVE-2022-49610

In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Prevent RSB underflow before vmenter On VMX, there are some balanced returns between the time the guest's SPECCTRL value is written, and the vmenter. Balanced returns matched by a preceding call are usually ok, but it's...

CVE-2022-49568 KVM: Don't null dereference ops->destroy

In the Linux kernel, the following vulnerability has been resolved: KVM: Don't null dereference ops-destroy A KVM device cleanup happens in either of two callbacks: 1 destroy which is called when the VM is being destroyed; 2 release which is called when a device fd is closed. Most KVM devices use...

CVE-2022-49568

CVE-2022-49568 affects the Linux kernel KVM code path, where a NULL dereference can occur during cleanup if destroy() is assumed non-NULL but is not (notably for some Book3s KVM devices that use release() instead). The root cause is an assumption in kvm_ioctl_create_device() that destroy() is alw...

CVE-2022-49568 KVM: Don't null dereference ops->destroy

In the Linux kernel, the following vulnerability has been resolved: KVM: Don't null dereference ops-destroy A KVM device cleanup happens in either of two callbacks: 1 destroy which is called when the VM is being destroyed; 2 release which is called when a device fd is closed. Most KVM devices use...

CVE-2022-49568

In the Linux kernel, the following vulnerability has been resolved: KVM: Don't null dereference ops-destroy A KVM device cleanup happens in either of two callbacks: 1 destroy which is called when the VM is being destroyed; 2 release which is called when a device fd is closed. Most KVM devices use...

CVE-2022-49562 KVM: x86: Use __try_cmpxchg_user() to update guest PTE A/D bits

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Use trycmpxchguser to update guest PTE A/D bits Use the recently introduced trycmpxchguser to update guest PTE A/D bits instead of mapping the PTE into kernel address space. The VMPFNMAP path is broken as it assumes tha...

CVE-2022-49562

CVE-2022-49562 concerns the Linux kernel KVM/x86 path, where guest PTE A/D bits were updated using a risky mapping approach. The fix switches to __try_cmpxchg_user() to update guest PTE A/D bits instead of mapping the PTE into kernel space, and highlights VM_PFNMAP addressing being conceptually w...

CVE-2022-49562 KVM: x86: Use __try_cmpxchg_user() to update guest PTE A/D bits

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Use trycmpxchguser to update guest PTE A/D bits Use the recently introduced trycmpxchguser to update guest PTE A/D bits instead of mapping the PTE into kernel address space. The VMPFNMAP path is broken as it assumes tha...

CVE-2022-49559 KVM: x86: Drop WARNs that assert a triple fault never "escapes" from L2

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Drop WARNs that assert a triple fault never "escapes" from L2 Remove WARNs that sanity check that KVM never lets a triple fault for L2 escape and incorrectly end up in L1. In normal operation, the sanity check is...

CVE-2022-49559

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Drop WARNs that assert a triple fault never "escapes" from L2 Remove WARNs that sanity check that KVM never lets a triple fault for L2 escape and incorrectly end up in L1. In normal operation, the sanity check is...

CVE-2022-49559 KVM: x86: Drop WARNs that assert a triple fault never "escapes" from L2

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Drop WARNs that assert a triple fault never "escapes" from L2 Remove WARNs that sanity check that KVM never lets a triple fault for L2 escape and incorrectly end up in L1. In normal operation, the sanity check is...

CVE-2022-49559

CVE-2022-49559 (Linux kernel, KVM/x86) is resolved. The issue involved dropping WARNs that incorrectly assumed KVM cannot let a triple fault (KVM_REQ_TRIPLE_FAULT) escape from L2 to L1. The vulnerability could be triggered when userspace injects a machine check while L2 is active with CR4.MCE=0, ...

CVE-2022-49557 x86/fpu: KVM: Set the base guest FPU uABI size to sizeof(struct kvm_xsave)

In the Linux kernel, the following vulnerability has been resolved: x86/fpu: KVM: Set the base guest FPU uABI size to sizeofstruct kvmxsave Set the starting uABI size of KVM's guest FPU to 'struct kvmxsave', i.e. to KVM's historical uABI size. When saving FPU state for usersapce, KVM well, now th...

CVE-2022-49557 x86/fpu: KVM: Set the base guest FPU uABI size to sizeof(struct kvm_xsave)

In the Linux kernel, the following vulnerability has been resolved: x86/fpu: KVM: Set the base guest FPU uABI size to sizeofstruct kvmxsave Set the starting uABI size of KVM's guest FPU to 'struct kvmxsave', i.e. to KVM's historical uABI size. When saving FPU state for usersapce, KVM well, now th...

CVE-2022-49557

In the Linux kernel, the following vulnerability has been resolved: x86/fpu: KVM: Set the base guest FPU uABI size to sizeofstruct kvmxsave Set the starting uABI size of KVM's guest FPU to 'struct kvmxsave', i.e. to KVM's historical uABI size. When saving FPU state for usersapce, KVM well, now th...

CVE-2022-49557

CVE-2022-49557 affects the Linux kernel in x86/fpu/KVM. The root cause is KVM’s guest FPU uABI size being set to the host default instead of KVM’s historic size, causing out-of-bounds writes to the XSAVE header when saving FPU state for guests on hosts without XSAVE. This can lead to data corrupt...

CVE-2022-49556 KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak For some sev ioctl interfaces, the length parameter that is passed maybe less than or equal to SEVFWBLOBMAXSIZE, but larger than the data that PSP firmwar...

CVE-2022-49556 KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak For some sev ioctl interfaces, the length parameter that is passed maybe less than or equal to SEVFWBLOBMAXSIZE, but larger than the data that PSP firmwar...