From: Mark McLoughlin <markmc@redhat.com>
Date: Fri, 18 Sep 2009 23:08:07 +0000 (-0300)
Subject: KVM: fix cpuid E2BIG handling for extended request types
X-Git-Tag: v2.6.30.9~19
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ae0661773f59370f84fb3d40897c2fc399d66442;p=thirdparty%2Fkernel%2Fstable.git

KVM: fix cpuid E2BIG handling for extended request types

(cherry picked from commit cb007648de83cf226d69ec76e1c01848b4e8e49f)

If we run out of cpuid entries for extended request types
we should return -E2BIG, just like we do for the standard
request types.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e23f5cb328204..8fdcec02e1dfa 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1438,6 +1438,10 @@ static int kvm_dev_ioctl_get_supported_cpuid(struct kvm_cpuid2 *cpuid,
 	for (func = 0x80000001; func <= limit && nent < cpuid->nent; ++func)
 		do_cpuid_ent(&cpuid_entries[nent], func, 0,
 			     &nent, cpuid->nent);
+	r = -E2BIG;
+	if (nent >= cpuid->nent)
+		goto out_free;
+
 	r = -EFAULT;
 	if (copy_to_user(entries, cpuid_entries,
 			 nent * sizeof(struct kvm_cpuid_entry2)))