Commit 6a544355 authored Oct 04, 2009 by Avi Kivity

KVM: Prevent overflow in KVM_GET_SUPPORTED_CPUID



The number of entries is multiplied by the entry size, which can
overflow on 32-bit hosts.  Bound the entry count instead.

Reported-by: David Wagner <daw@cs.berkeley.edu>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>

parent eb5109e3

arch/x86/kvm/x86.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1591,6 +1591,8 @@ static int kvm_dev_ioctl_get_supported_cpuid(struct kvm_cpuid2 *cpuid,

		if (cpuid->nent < 1)
		goto out;
		if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
		cpuid->nent = KVM_MAX_CPUID_ENTRIES;
		r = -ENOMEM;
		cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
		if (!cpuid_entries)