Vulnerabilities > CVE-2021-47062 - NULL Pointer Dereference vulnerability in Linux Kernel
Attack vector
LOCAL Attack complexity
LOW Privileges required
LOW Confidentiality impact
NONE Integrity impact
NONE Availability impact
HIGH Summary
In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Use online_vcpus, not created_vcpus, to iterate over vCPUs Use the kvm_for_each_vcpu() helper to iterate over vCPUs when encrypting VMSAs for SEV, which effectively switches to use online_vcpus instead of created_vcpus. This fixes a possible null-pointer dereference as created_vcpus does not guarantee a vCPU exists, since it is updated at the very beginning of KVM_CREATE_VCPU. created_vcpus exists to allow the bulk of vCPU creation to run in parallel, while still correctly restricting the max number of max vCPUs.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
References
- https://git.kernel.org/stable/c/ba7bf5d6336aa9c0d977b161bfa420c56d46ee40
- https://git.kernel.org/stable/c/ba7bf5d6336aa9c0d977b161bfa420c56d46ee40
- https://git.kernel.org/stable/c/bd0cced2ae93195668f983d443f7f17e8efd24d2
- https://git.kernel.org/stable/c/bd0cced2ae93195668f983d443f7f17e8efd24d2
- https://git.kernel.org/stable/c/c36b16d29f3af5f32fc1b2a3401bf48f71cabee1
- https://git.kernel.org/stable/c/c36b16d29f3af5f32fc1b2a3401bf48f71cabee1