Module Name: src
Committed By: kamil
Date: Mon Apr 6 08:20:05 UTC 2020
Modified Files:
src/sys/kern: kern_exec.c kern_fork.c kern_proc.c kern_sig.c
src/sys/sys: proc.h
Log Message:
Reintroduce struct proc::p_oppid
Relying on p_opptr is not safe as there is a race between:
- spawner giving a birth to a child process and being killed
- spawnee accessng p_opptr and reporting TRAP_CHLD
PR kern/54786 by Andreas Gustafsson
To generate a diff of this commit:
cvs rdiff -u -r1.494 -r1.495 src/sys/kern/kern_exec.c
cvs rdiff -u -r1.220 -r1.221 src/sys/kern/kern_fork.c
cvs rdiff -u -r1.242 -r1.243 src/sys/kern/kern_proc.c
cvs rdiff -u -r1.386 -r1.387 src/sys/kern/kern_sig.c
cvs rdiff -u -r1.361 -r1.362 src/sys/sys/proc.h
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/kern_exec.c
diff -u src/sys/kern/kern_exec.c:1.494 src/sys/kern/kern_exec.c:1.495
--- src/sys/kern/kern_exec.c:1.494 Sun Apr 5 20:53:17 2020
+++ src/sys/kern/kern_exec.c Mon Apr 6 08:20:05 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_exec.c,v 1.494 2020/04/05 20:53:17 christos Exp $ */
+/* $NetBSD: kern_exec.c,v 1.495 2020/04/06 08:20:05 kamil Exp $ */
/*-
* Copyright (c) 2008, 2019, 2020 The NetBSD Foundation, Inc.
@@ -62,7 +62,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_exec.c,v 1.494 2020/04/05 20:53:17 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_exec.c,v 1.495 2020/04/06 08:20:05 kamil Exp $");
#include "opt_exec.h"
#include "opt_execfmt.h"
@@ -2660,6 +2660,7 @@ do_posix_spawn(struct lwp *l1, pid_t *pi
if ((p1->p_slflag & (PSL_TRACEPOSIX_SPAWN|PSL_TRACED)) ==
(PSL_TRACEPOSIX_SPAWN|PSL_TRACED)) {
proc_changeparent(p2, p1->p_pptr);
+ p2->p_oppid = p1->p_pid;
}
LIST_INSERT_AFTER(p1, p2, p_pglist);
Index: src/sys/kern/kern_fork.c
diff -u src/sys/kern/kern_fork.c:1.220 src/sys/kern/kern_fork.c:1.221
--- src/sys/kern/kern_fork.c:1.220 Sun Apr 5 20:53:17 2020
+++ src/sys/kern/kern_fork.c Mon Apr 6 08:20:05 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_fork.c,v 1.220 2020/04/05 20:53:17 christos Exp $ */
+/* $NetBSD: kern_fork.c,v 1.221 2020/04/06 08:20:05 kamil Exp $ */
/*-
* Copyright (c) 1999, 2001, 2004, 2006, 2007, 2008, 2019
@@ -68,7 +68,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_fork.c,v 1.220 2020/04/05 20:53:17 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_fork.c,v 1.221 2020/04/06 08:20:05 kamil Exp $");
#include "opt_ktrace.h"
#include "opt_dtrace.h"
@@ -511,8 +511,10 @@ fork1(struct lwp *l1, int flags, int exi
/*
* Trace fork(2) and vfork(2)-like events on demand in a debugger.
*/
- if (tracefork(p1, flags) || tracevfork(p1, flags))
+ if (tracefork(p1, flags) || tracevfork(p1, flags)) {
proc_changeparent(p2, p1->p_pptr);
+ p2->p_oppid = p1->p_pid;
+ }
LIST_INSERT_AFTER(p1, p2, p_pglist);
LIST_INSERT_HEAD(&allproc, p2, p_list);
Index: src/sys/kern/kern_proc.c
diff -u src/sys/kern/kern_proc.c:1.242 src/sys/kern/kern_proc.c:1.243
--- src/sys/kern/kern_proc.c:1.242 Sun Feb 23 22:14:03 2020
+++ src/sys/kern/kern_proc.c Mon Apr 6 08:20:05 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_proc.c,v 1.242 2020/02/23 22:14:03 ad Exp $ */
+/* $NetBSD: kern_proc.c,v 1.243 2020/04/06 08:20:05 kamil Exp $ */
/*-
* Copyright (c) 1999, 2006, 2007, 2008, 2020 The NetBSD Foundation, Inc.
@@ -62,7 +62,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_proc.c,v 1.242 2020/02/23 22:14:03 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_proc.c,v 1.243 2020/04/06 08:20:05 kamil Exp $");
#ifdef _KERNEL_OPT
#include "opt_kstack.h"
@@ -2270,6 +2270,7 @@ fill_proc(const struct proc *psrc, struc
COND_SET_VALUE(p->p_sigpend, psrc->p_sigpend, allowaddr);
COND_SET_VALUE(p->p_lwpctl, psrc->p_lwpctl, allowaddr);
p->p_ppid = psrc->p_ppid;
+ p->p_oppid = psrc->p_oppid;
COND_SET_VALUE(p->p_path, psrc->p_path, allowaddr);
COND_SET_VALUE(p->p_sigctx, psrc->p_sigctx, allowaddr);
p->p_nice = psrc->p_nice;
Index: src/sys/kern/kern_sig.c
diff -u src/sys/kern/kern_sig.c:1.386 src/sys/kern/kern_sig.c:1.387
--- src/sys/kern/kern_sig.c:1.386 Sun Apr 5 20:53:17 2020
+++ src/sys/kern/kern_sig.c Mon Apr 6 08:20:05 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_sig.c,v 1.386 2020/04/05 20:53:17 christos Exp $ */
+/* $NetBSD: kern_sig.c,v 1.387 2020/04/06 08:20:05 kamil Exp $ */
/*-
* Copyright (c) 2006, 2007, 2008, 2019 The NetBSD Foundation, Inc.
@@ -70,7 +70,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_sig.c,v 1.386 2020/04/05 20:53:17 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_sig.c,v 1.387 2020/04/06 08:20:05 kamil Exp $");
#include "opt_ptrace.h"
#include "opt_dtrace.h"
@@ -1693,12 +1693,12 @@ eventswitchchild(struct proc *p, int cod
{
mutex_enter(proc_lock);
mutex_enter(p->p_lock);
- if (!(p->p_slflag & PSL_TRACED) || p->p_opptr == NULL) {
+ if (!(p->p_slflag & PSL_TRACED)) {
mutex_exit(p->p_lock);
mutex_exit(proc_lock);
return;
}
- eventswitch(code, pe_report_event, p->p_opptr->p_pid);
+ eventswitch(code, pe_report_event, p->p_oppid);
}
/*
Index: src/sys/sys/proc.h
diff -u src/sys/sys/proc.h:1.361 src/sys/sys/proc.h:1.362
--- src/sys/sys/proc.h:1.361 Sun Apr 5 20:53:46 2020
+++ src/sys/sys/proc.h Mon Apr 6 08:20:05 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: proc.h,v 1.361 2020/04/05 20:53:46 christos Exp $ */
+/* $NetBSD: proc.h,v 1.362 2020/04/06 08:20:05 kamil Exp $ */
/*-
* Copyright (c) 2006, 2007, 2008, 2020 The NetBSD Foundation, Inc.
@@ -311,6 +311,7 @@ struct proc {
sigpend_t p_sigpend; /* p: pending signals */
struct lcproc *p_lwpctl; /* p, a: _lwp_ctl() information */
pid_t p_ppid; /* :: cached parent pid */
+ pid_t p_oppid; /* :: cached original parent pid */
char *p_path; /* :: full pathname of executable */
/*
