KVM: x86 emulator: Check segment limits in real mode too

Segment limits are verified in real mode, not just protected mode.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index f8b27cd2a6cb499fbe4b2353bda47774e33d9576..5b1c701cd6d04f04160b274e7d204fa342e1dec3 100644 (file)
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -668,8 +668,6 @@ static int __linearize(struct x86_emulate_ctxt *ctxt,
 
        la = seg_base(ctxt, addr.seg) + addr.ea;
        switch (ctxt->mode) {
-       case X86EMUL_MODE_REAL:
-               break;
        case X86EMUL_MODE_PROT64:
                if (((signed long)la << 16) >> 16 != la)
                        return emulate_gp(ctxt, 0);
@@ -699,7 +697,10 @@ static int __linearize(struct x86_emulate_ctxt *ctxt,
                                goto bad;
                }
                cpl = ctxt->ops->cpl(ctxt);
-               rpl = sel & 3;
+               if (ctxt->mode == X86EMUL_MODE_REAL)
+                       rpl = 0;
+               else
+                       rpl = sel & 3;
                cpl = max(cpl, rpl);
                if (!(desc.type & 8)) {
                        /* data segment */