Module Name: src
Committed By: riastradh
Date: Thu Dec 7 03:25:51 UTC 2017
Modified Files:
src/sys/arch/amd64/amd64: trap.c
Log Message:
Attempt to clarify panic messages for null pointer access/execute.
To generate a diff of this commit:
cvs rdiff -u -r1.105 -r1.106 src/sys/arch/amd64/amd64/trap.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/amd64/amd64/trap.c
diff -u src/sys/arch/amd64/amd64/trap.c:1.105 src/sys/arch/amd64/amd64/trap.c:1.106
--- src/sys/arch/amd64/amd64/trap.c:1.105 Sat Dec 2 12:40:03 2017
+++ src/sys/arch/amd64/amd64/trap.c Thu Dec 7 03:25:51 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: trap.c,v 1.105 2017/12/02 12:40:03 maxv Exp $ */
+/* $NetBSD: trap.c,v 1.106 2017/12/07 03:25:51 riastradh Exp $ */
/*
* Copyright (c) 1998, 2000, 2017 The NetBSD Foundation, Inc.
@@ -64,7 +64,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.105 2017/12/02 12:40:03 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.106 2017/12/07 03:25:51 riastradh Exp $");
#include "opt_ddb.h"
#include "opt_kgdb.h"
@@ -518,16 +518,26 @@ trap(struct trapframe *frame)
if (frame->tf_err & PGEX_X) {
/* SMEP might have brought us here */
- if (cr2 < VM_MAXUSER_ADDRESS)
- panic("prevented execution of %p (SMEP)",
- (void *)cr2);
+ if (cr2 < VM_MAXUSER_ADDRESS) {
+ if (cr2 == 0)
+ panic("prevented jump to null"
+ " instruction pointer (SMEP)");
+ else
+ panic("prevented execution of"
+ " user address %p (SMEP)",
+ (void *)cr2);
+ }
}
if (cr2 < VM_MAXUSER_ADDRESS) {
/* SMAP might have brought us here */
- if (onfault_handler(pcb, frame) == NULL)
- panic("prevented access to %p (SMAP)",
+ if (onfault_handler(pcb, frame) == NULL) {
+ panic("prevented %s %p (SMAP)",
+ (cr2 < PAGE_SIZE
+ ? "null pointer dereference at"
+ : "access to"),
(void *)cr2);
+ }
}
goto faultcommon;
