Module Name: src
Committed By: kamil
Date: Tue May 1 14:09:53 UTC 2018
Modified Files:
src/sys/kern: sys_ptrace_common.c
Log Message:
Add additional hardening in PT_TRACE_ME and PT_ATTACH
Prohibit:
- calling PT_TRACE_ME by initproc (PID1),
- calling PT_ATTACH by initproc (PID1).
PID1 and its parent cannot become a tracer.
Sponsored by <The NetBSD Foundation>
To generate a diff of this commit:
cvs rdiff -u -r1.38 -r1.39 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:1.38 src/sys/kern/sys_ptrace_common.c:1.39
--- src/sys/kern/sys_ptrace_common.c:1.38 Sun Apr 29 04:28:09 2018
+++ src/sys/kern/sys_ptrace_common.c Tue May 1 14:09:53 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: sys_ptrace_common.c,v 1.38 2018/04/29 04:28:09 kamil Exp $ */
+/* $NetBSD: sys_ptrace_common.c,v 1.39 2018/05/01 14:09:53 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 1.38 2018/04/29 04:28:09 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_ptrace_common.c,v 1.39 2018/05/01 14:09:53 kamil Exp $");
#ifdef _KERNEL_OPT
#include "opt_ptrace.h"
@@ -385,7 +385,13 @@ ptrace_allowed(struct lwp *l, int req, s
return EPERM;
/*
- * (2) the child is already traced.
+ * (2) the process is initproc, or
+ */
+ if (p == initproc)
+ return EPERM;
+
+ /*
+ * (3) the child is already traced.
*/
if (ISSET(p->p_slflag, PSL_TRACED))
return EBUSY;
@@ -401,19 +407,25 @@ ptrace_allowed(struct lwp *l, int req, s
return EINVAL;
/*
- * (2) it's a system process
+ * (2) it's a system process,
*/
if (t->p_flag & PK_SYSTEM)
return EPERM;
/*
- * (3) it's already being traced, or
+ * (3) the tracer is initproc,
+ */
+ if (p == initproc)
+ return EPERM;
+
+ /*
+ * (4) it's already being traced, or
*/
if (ISSET(t->p_slflag, PSL_TRACED))
return EBUSY;
/*
- * (4) the tracer is chrooted, and its root directory is
+ * (5) the tracer is chrooted, and its root directory is
* not at or above the root directory of the tracee
*/
mutex_exit(t->p_lock); /* XXXSMP */
