KVM: Improve create VCPU parameter (CVE-2013-4587)
commit 338c7dbadd upstream.
In multiple functions the vcpu_id is used as an offset into a bitfield. Ag
malicious user could specify a vcpu_id greater than 255 in order to set or
clear bits in kernel memory. This could be used to elevate priveges in the
kernel. This patch verifies that the vcpu_id provided is less than 255.
The api documentation already specifies that the vcpu_id must be less than
max_vcpus, but this is currently not checked.
Reported-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
committed by
Greg Kroah-Hartman
parent
2925f142d8
commit
41fe7fa8fd
@ -1893,6 +1893,9 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
|
||||
int r;
|
||||
struct kvm_vcpu *vcpu, *v;
|
||||
|
||||
if (id >= KVM_MAX_VCPUS)
|
||||
return -EINVAL;
|
||||
|
||||
vcpu = kvm_arch_vcpu_create(kvm, id);
|
||||
if (IS_ERR(vcpu))
|
||||
return PTR_ERR(vcpu);
|
||||
|
||||
Reference in New Issue
Block a user