From: Andrew Cooper <andrew.cooper3@citrix.com>
Date: Wed, 11 Jan 2017 17:51:44 +0000 (+0000)
Subject: x86/sysctl: Fix NULL pointer dereference in error path
X-Git-Tag: archive/raspbian/4.11.1-1+rpi1~1^2~66^2~2991
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=2704c78aaa156e6843681ee344dd0ce75dbc63b2;p=xen.git

x86/sysctl: Fix NULL pointer dereference in error path

This was introduced by c/s c38869e711 "x86/cpuid: Drop the temporary linear
feature bitmap from struct cpuid_policy", and caught by Coverity.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---

diff --git a/xen/arch/x86/sysctl.c b/xen/arch/x86/sysctl.c
index 87da541841..b8c30d4c04 100644
--- a/xen/arch/x86/sysctl.c
+++ b/xen/arch/x86/sysctl.c
@@ -230,8 +230,8 @@ long arch_do_sysctl(
         /* Bad featureset index? */
         if ( !p )
             ret = -EINVAL;
-
-        cpuid_policy_to_featureset(p, featureset);
+        else
+            cpuid_policy_to_featureset(p, featureset);
 
         /* Copy the requested featureset into place. */
         if ( !ret && copy_to_guest(sysctl->u.cpu_featureset.features,