diff options
author | Andy Honig <ahonig@google.com> | 2013-11-19 00:09:22 +0000 |
---|---|---|
committer | Willy Tarreau <w@1wt.eu> | 2014-05-19 07:54:33 +0200 |
commit | ba6e9bbbd6e3e28d92ff43981c2354307c095b7c (patch) | |
tree | 8ce4da6333d37581928064437c11f3a613737e20 | |
parent | 4b500c7ff030f35aa6f8badf2f243bc259021e39 (diff) |
KVM: Improve create VCPU parameter (CVE-2013-4587)
commit 338c7dbadd2671189cec7faf64c84d01071b3f96 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>
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
-rw-r--r-- | virt/kvm/kvm_main.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 82b6fdca21ba..3b9443be3918 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1846,6 +1846,9 @@ 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); |