CVE-2021-47062
Vulnerability from cvelistv5
Published
2024-02-29 22:37
Modified
2024-12-19 07:34
Severity ?
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.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ba7bf5d6336aa9c0d977b161bfa420c56d46ee40Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/bd0cced2ae93195668f983d443f7f17e8efd24d2Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c36b16d29f3af5f32fc1b2a3401bf48f71cabee1Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/ba7bf5d6336aa9c0d977b161bfa420c56d46ee40Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/bd0cced2ae93195668f983d443f7f17e8efd24d2Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/c36b16d29f3af5f32fc1b2a3401bf48f71cabee1Patch
Impacted products
Vendor Product Version
Linux Linux Version: 5.11
Show details on NVD website

To clipboard 

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