Module Name: src
Committed By: kamil
Date: Wed May 1 17:02:40 UTC 2019
Modified Files:
src/sys/kern: sys_ptrace_common.c
Log Message:
Disallow resuming program with PC=0x0 in ptrace(2)
If the address parameter is 0, report error.
It's a popular mistake to set Program Counter to 0x0.
In certain kernels this is allowable parameter and causes
portability issue.
Disallow explicitly zeroed PC, instead of triggering
a harder to debug crash later.
To generate a diff of this commit:
cvs rdiff -u -r1.50 -r1.51 src/sys/kern/sys_ptrace_common.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/kern/sys_ptrace_common.c
diff -u src/sys/kern/sys_ptrace_common.c:1.50 src/sys/kern/sys_ptrace_common.c:1.51
--- src/sys/kern/sys_ptrace_common.c:1.50 Tue Apr 30 22:32:01 2019
+++ src/sys/kern/sys_ptrace_common.c Wed May 1 17:02:40 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: sys_ptrace_common.c,v 1.50 2019/04/30 22:32:01 kamil Exp $ */
+/* $NetBSD: sys_ptrace_common.c,v 1.51 2019/05/01 17:02:40 kamil Exp $ */
/*-
* Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
@@ -118,7 +118,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_ptrace_common.c,v 1.50 2019/04/30 22:32:01 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_ptrace_common.c,v 1.51 2019/05/01 17:02:40 kamil Exp $");
#ifdef _KERNEL_OPT
#include "opt_ptrace.h"
@@ -1246,6 +1246,21 @@ do_ptrace(struct ptrace_methods *ptm, st
}
}
+ /*
+ * If the address parameter is 0, report error.
+ *
+ * It's a popular mistake to set Program Counter to 0x0.
+ * In certain kernels this is allowable parameter and causes
+ * portability issue.
+ *
+ * Disallow explicitly zeroed PC, instead of triggering
+ * a harder to debug crash later.
+ */
+ if (addr == 0) {
+ error = EINVAL;
+ break;
+ }
+
/* If the address parameter is not (int *)1, set the pc. */
if ((int *)addr != (int *)1) {
error = process_set_pc(lt, addr);
