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>
master commit: cb34a2fa162184b150d48a3b6f385bacbec22ce7
master date: 2021-01-18 17:50:11 +0000

diff --git a/xen/arch/x86/mm/mem_sharing.c b/xen/arch/x86/mm/mem_sharing.c
index c428fd16cef08e7b41fa207b6e83ce3761f911f0..468bbcfa6787aa6ea47a0b72ac69edb9249f486d 100644 (file)
--- a/xen/arch/x86/mm/mem_sharing.c
+++ b/xen/arch/x86/mm/mem_sharing.c
@@ -1628,7 +1628,7 @@ 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) )