Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: nv: Fix life cycle of the nested_mmus array The nested_mmus array holds the shadow page tables that are used when a guest is running a nested context. These structures are allocated on VCPU_INIT for whole guest, which implies that they may have to be relocated as the array grows. Should a VCPU_INIT occur whilst a vcpu is actively running an L2 and that the allocation requires relocation, that vcpu will still be running with a pointer to the previous structure, which will have been freed. Fix this by turning the array of structures to an array of pointers, which is now allocated at VM creation, sized to the absolute maximum that KVM can handle. In turn, each VCPU_INIT contributes S2_MMU_PER_VCPU to the pool. No reallocation is ever performed, and the life cycle of each object is much clearer: - the nested_mmus array is allocated in kvm_init_nested(), and freed in kvm_arch_destroy_vm() - s2_mmu structures are allocated in kvm_vcpu_init_nested(), and freed on kvm_arch_flush_shadow_all() Finally, the freeing of vcpu->arch.vncr_array is made consistent rather than being done on some failure paths, but not others.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 4f128f8e1aaac189f83d0f828bcdb2986d8d2e51 before ea242bdc29e8a8ff0e2447a64b3841114779f3af; affected 4f128f8e1aaac189f83d0f828bcdb2986d8d2e51 before 81e3f065a6485626f816d791dfd5e00ddd12eff5; affected 4f128f8e1aaac189f83d0f828bcdb2986d8d2e51 before 512c93f4461b9a3735987f48423d438a9cd49e6a; affected 4f128f8e1aaac189f83d0f828bcdb2986d8d2e51 before 33346f8960c7bb6a3b4e273b5cfe25c5a8be349f |
| Linux / Linux | affected 6.11; unaffected 0 before 6.11; unaffected 6.12.113 through 6.12.*; unaffected 6.18.56 through 6.18.*; unaffected 7.2.9 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.