From: Marc Zyngier maz@kernel.org
stable inclusion from stable-v5.10.217 commit 4563a0afd99e1d86acb7d54a0809ed27d273a7f6 category: cleanup bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9UOQA CVE: CVE-2024-36953
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 4e7728c81a54b17bd33be402ac140bc11bb0c4f4 ]
When parsing a GICv2 attribute that contains a cpuid, handle this as the vcpu_id, not a vcpu_idx, as userspace cannot really know the mapping between the two. For this, use kvm_get_vcpu_by_id() instead of kvm_get_vcpu().
Take this opportunity to get rid of the pointless check against online_vcpus, which doesn't make much sense either, and switch to FIELD_GET as a way to extract the vcpu_id.
Reviewed-by: Zenghui Yu yuzenghui@huawei.com Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20230927090911.3355209-5-maz@kernel.org Signed-off-by: Oliver Upton oliver.upton@linux.dev Stable-dep-of: 6ddb4f372fc6 ("KVM: arm64: vgic-v2: Check for non-NULL vCPU in vgic_v2_parse_attr()") Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Liu Shixin liushixin2@huawei.com --- arch/arm64/kvm/vgic/vgic-kvm-device.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/arch/arm64/kvm/vgic/vgic-kvm-device.c b/arch/arm64/kvm/vgic/vgic-kvm-device.c index 7740995de982..640cfa0c0f4c 100644 --- a/arch/arm64/kvm/vgic/vgic-kvm-device.c +++ b/arch/arm64/kvm/vgic/vgic-kvm-device.c @@ -286,13 +286,9 @@ int vgic_v2_parse_attr(struct kvm_device *dev, struct kvm_device_attr *attr, { int cpuid;
- cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >> - KVM_DEV_ARM_VGIC_CPUID_SHIFT; + cpuid = FIELD_GET(KVM_DEV_ARM_VGIC_CPUID_MASK, attr->attr);
- if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) - return -EINVAL; - - reg_attr->vcpu = kvm_get_vcpu(dev->kvm, cpuid); + reg_attr->vcpu = kvm_get_vcpu_by_id(dev->kvm, cpuid); reg_attr->addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
return 0;