Commit 58b7825b authored by Gleb Natapov's avatar Gleb Natapov Committed by Marcelo Tosatti
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KVM: emulator: fix real mode segment checks in address linearization 



In real mode CS register is writable, so do not #GP on write.

Signed-off-by: default avatarGleb Natapov <gleb@redhat.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 0b26b588

arch/x86/kvm/emulate.c

+3 −2
Original line number Diff line number Diff line
@@ -677,8 +677,9 @@ static int __linearize(struct x86_emulate_ctxt *ctxt, 
						addr.seg);

		if (!usable)

			goto bad;

		/* code segment or read-only data segment */

		if (((desc.type & 8) || !(desc.type & 2)) && write)

		/* code segment in protected mode or read-only data segment */

		if ((((ctxt->mode != X86EMUL_MODE_REAL) && (desc.type & 8))

					|| !(desc.type & 2)) && write)

			goto bad;

		/* unreadable code segment */

		if (!fetch && (desc.type & 8) && !(desc.type & 2))