KVM: x86 emulator: fix src, dst value initialization

Some operand fetches are less than the machine word size and can result in
stale bits if used together with operands of different sizes.

Signed-off-by: Nitin A Kamble <nitin.a.kamble@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c
index cf8db670df7f47efc3e4a84f09d505a5d6d5bd2c..7360a71094f57cdb3b44fb36cf1e7a9c18833309 100644 (file)
--- a/drivers/kvm/x86_emulate.c
+++ b/drivers/kvm/x86_emulate.c
@@ -827,6 +827,7 @@ done_prefixes:
              srcmem_common:
                src.type = OP_MEM;
                src.ptr = (unsigned long *)cr2;
+               src.val = 0;
                if ((rc = ops->read_emulated((unsigned long)src.ptr,
                                             &src.val, src.bytes, ctxt->vcpu)) != 0)
                        goto done;
@@ -891,6 +892,7 @@ done_prefixes:
                dst.type = OP_MEM;
                dst.ptr = (unsigned long *)cr2;
                dst.bytes = (d & ByteOp) ? 1 : op_bytes;
+               dst.val = 0;
                if (d & BitOp) {
                        unsigned long mask = ~(dst.bytes * 8 - 1);