From b62c38079ebaa36c0ccd77647fd1fdd46315bc98 Mon Sep 17 00:00:00 2001 From: Eric Northup Date: Tue, 3 Nov 2015 18:03:53 +0100 Subject: KVM: x86: work around infinite loop in microcode when #AC is delivered commit 54a20552e1eae07aa240fa370a0293e006b5faed upstream. It was found that a guest can DoS a host by triggering an infinite stream of "alignment check" (#AC) exceptions. This causes the microcode to enter an infinite loop where the core never receives another interrupt. The host kernel panics pretty quickly due to the effects (CVE-2015-5307). Signed-off-by: Eric Northup Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/uapi/asm/svm.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/include/uapi/asm/svm.h') diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h index b5d7640abc5d..8a4add8e4639 100644 --- a/arch/x86/include/uapi/asm/svm.h +++ b/arch/x86/include/uapi/asm/svm.h @@ -100,6 +100,7 @@ { SVM_EXIT_EXCP_BASE + UD_VECTOR, "UD excp" }, \ { SVM_EXIT_EXCP_BASE + PF_VECTOR, "PF excp" }, \ { SVM_EXIT_EXCP_BASE + NM_VECTOR, "NM excp" }, \ + { SVM_EXIT_EXCP_BASE + AC_VECTOR, "AC excp" }, \ { SVM_EXIT_EXCP_BASE + MC_VECTOR, "MC excp" }, \ { SVM_EXIT_INTR, "interrupt" }, \ { SVM_EXIT_NMI, "nmi" }, \ -- cgit v1.2.3