From: Tamas K Lengyel <tamas@tklengyel.com>
Date: Mon, 18 Jan 2021 17:23:06 +0000 (-0700)
Subject: x86/mem_sharing: fix uninitialized 'preempted' variable
X-Git-Tag: 4.15.0-rc1~273
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=cb34a2fa162184b150d48a3b6f385bacbec22ce7;p=people%2Fjgross%2Fxen.git

x86/mem_sharing: fix uninitialized 'preempted' variable

UBSAN catches an uninitialized use of the 'preempted' variable in
fork_hap_allocation when there is no preemption.

Fixes: 41548c5472a ("mem_sharing: VM forking")
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
---

diff --git a/xen/arch/x86/mm/mem_sharing.c b/xen/arch/x86/mm/mem_sharing.c
index c8a6d11b90..adaeab4612 100644
--- a/xen/arch/x86/mm/mem_sharing.c
+++ b/xen/arch/x86/mm/mem_sharing.c
@@ -1644,7 +1644,7 @@ static int copy_vcpu_settings(struct domain *cd, const struct domain *d)
 static int fork_hap_allocation(struct domain *cd, struct domain *d)
 {
     int rc;
-    bool preempted;
+    bool preempted = false;
     unsigned long mb = hap_get_allocation(d);
 
     if ( mb == hap_get_allocation(cd) )