From: deraadt <deraadt@openbsd.org>
Date: Wed, 21 Feb 2024 15:53:07 +0000 (+0000)
Subject: create a new code ILL_BTCFI associated with SIGILL for trap faults which
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=88580652a3669007813512ab28f5ee7ceeae4a78;p=openbsd

create a new code ILL_BTCFI associated with SIGILL for trap faults which
indicate missing indirect branch target instructions (on the two
architectures which currently have this).  This becomes nicely visible in
kdump:
  6526 cat      PSIG  SIGILL SIG_DFL code=ILL_BTCFI addr=0x438fad6a990 trapno=21
ok kettenis sthen miod rsadowski
---

diff --git a/sys/arch/amd64/amd64/trap.c b/sys/arch/amd64/amd64/trap.c
index 4df17486b78..a40de920271 100644
--- a/sys/arch/amd64/amd64/trap.c
+++ b/sys/arch/amd64/amd64/trap.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: trap.c,v 1.104 2024/01/31 06:06:28 guenther Exp $	*/
+/*	$OpenBSD: trap.c,v 1.105 2024/02/21 15:53:07 deraadt Exp $	*/
 /*	$NetBSD: trap.c,v 1.2 2003/05/04 23:51:56 fvdl Exp $	*/
 
 /*-
@@ -424,7 +424,7 @@ usertrap(struct trapframe *frame)
 		break;
 	case T_CP:
 		sig = SIGILL;
-		code = (frame->tf_err & 0x7fff) < 4 ? ILL_ILLOPC
+		code = (frame->tf_err & 0x7fff) < 4 ? ILL_BTCFI
 		    : ILL_BADSTK;
 		break;
 
diff --git a/sys/arch/arm64/arm64/trap.c b/sys/arch/arm64/arm64/trap.c
index bbe6b04c538..c420b747768 100644
--- a/sys/arch/arm64/arm64/trap.c
+++ b/sys/arch/arm64/arm64/trap.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: trap.c,v 1.47 2023/12/26 09:19:15 kettenis Exp $ */
+/* $OpenBSD: trap.c,v 1.48 2024/02/21 15:53:07 deraadt Exp $ */
 /*-
  * Copyright (c) 2014 Andrew Turner
  * All rights reserved.
@@ -286,7 +286,7 @@ do_el0_sync(struct trapframe *frame)
 	case EXCP_BRANCH_TGT:
 		curcpu()->ci_flush_bp();
 		sv.sival_ptr = (void *)frame->tf_elr;
-		trapsignal(p, SIGILL, esr, ILL_ILLOPC, sv);
+		trapsignal(p, SIGILL, esr, ILL_BTCFI, sv);
 		break;
 	case EXCP_FPAC:
 		curcpu()->ci_flush_bp();
diff --git a/sys/sys/siginfo.h b/sys/sys/siginfo.h
index c534ab10474..d071f4fe5ea 100644
--- a/sys/sys/siginfo.h
+++ b/sys/sys/siginfo.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: siginfo.h,v 1.13 2022/10/25 16:08:26 kettenis Exp $	*/
+/*	$OpenBSD: siginfo.h,v 1.14 2024/02/21 15:53:07 deraadt Exp $	*/
 
 /*
  * Copyright (c) 1997 Theo de Raadt
@@ -61,7 +61,8 @@ union sigval {
 #define ILL_PRVREG	6	/* privileged register */
 #define ILL_COPROC	7	/* co-processor */
 #define ILL_BADSTK	8	/* bad stack */
-#define NSIGILL		8
+#define ILL_BTCFI	9	/* IBT missing on indirect call */
+#define NSIGILL		9
 
 #define EMT_TAGOVF	1	/* tag overflow */
 #define NSIGEMT		1