A failure to decode the instruction can cause a NULL pointer access. This is fixed simply by moving the "done" label as close as possible to the return. This fixes CVE-2014-8481. Reported-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Fixes: 41061cdb98a0bec464278b4db8e894a3121671f5 Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> --- arch/x86/kvm/emulate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 02c8ea804aaf..eb3b1c46f995 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -4580,10 +4580,10 @@ done_prefixes: /* Decode and fetch the destination operand: register or memory. */ rc = decode_operand(ctxt, &ctxt->dst, (ctxt->d >> DstShift) & OpMask); -done: if (ctxt->rip_relative) ctxt->memopp->addr.mem.ea += ctxt->_eip; +done: return (rc != X86EMUL_CONTINUE) ? EMULATION_FAILED : EMULATION_OK; } -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
