Module Name: src
Committed By: martin
Date: Tue Oct 15 18:32:13 UTC 2019
Modified Files:
src/sys/compat/sys [netbsd-9]: siginfo.h
src/sys/kern [netbsd-9]: kern_exec.c kern_fork.c kern_lwp.c kern_sig.c
sys_lwp.c sys_ptrace_common.c
src/sys/sys [netbsd-9]: siginfo.h signalvar.h
Log Message:
Pull up following revision(s) (requested by kamil in ticket #311):
sys/sys/siginfo.h: revision 1.34
sys/kern/sys_ptrace_common.c: revision 1.59
sys/kern/sys_lwp.c: revision 1.70
sys/compat/sys/siginfo.h: revision 1.8
sys/kern/kern_sig.c: revision 1.365
sys/kern/kern_lwp.c: revision 1.203
sys/sys/signalvar.h: revision 1.96
sys/kern/kern_exec.c: revision 1.482
sys/kern/kern_fork.c: revision 1.214
Move TRAP_CHLD/TRAP_LWP ptrace information from struct proc to siginfo
Storing struct ptrace_state information inside struct proc was vulnerable
to synchronization bugs, as multiple events emitted in the same time were
overwritting other ones.
Cache the original parent process id in p_oppid. Reusing here p_opptr is
in theory prone to slight race codition.
Change the semantics of PT_GET_PROCESS_STATE, reutning EINVAL for calls
prompting for the value in cases when there wasn't registered an
appropriate event.
Add an alternative approach to check the ptrace_state information, directly
from the siginfo_t value returned from PT_GET_SIGINFO. The original
PT_GET_PROCESS_STATE approach is kept for compat with older NetBSD and
OpenBSD. New code is recommended to keep using PT_GET_PROCESS_STATE.
Add a couple of compile-time asserts for assumptions in the code.
No functional change intended in existing ptrace(2) software.
All ATF ptrace(2) and ATF GDB tests pass.
This change improves reliability of the threading ptrace(2) code.
To generate a diff of this commit:
cvs rdiff -u -r1.7 -r1.7.2.1 src/sys/compat/sys/siginfo.h
cvs rdiff -u -r1.478 -r1.478.2.1 src/sys/kern/kern_exec.c
cvs rdiff -u -r1.213 -r1.213.2.1 src/sys/kern/kern_fork.c
cvs rdiff -u -r1.202 -r1.202.2.1 src/sys/kern/kern_lwp.c
cvs rdiff -u -r1.364 -r1.364.2.1 src/sys/kern/kern_sig.c
cvs rdiff -u -r1.69 -r1.69.2.1 src/sys/kern/sys_lwp.c
cvs rdiff -u -r1.58.2.1 -r1.58.2.2 src/sys/kern/sys_ptrace_common.c
cvs rdiff -u -r1.33 -r1.33.2.1 src/sys/sys/siginfo.h
cvs rdiff -u -r1.93 -r1.93.2.1 src/sys/sys/signalvar.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/compat/sys/siginfo.h
diff -u src/sys/compat/sys/siginfo.h:1.7 src/sys/compat/sys/siginfo.h:1.7.2.1
--- src/sys/compat/sys/siginfo.h:1.7 Sun Jun 30 08:49:21 2019
+++ src/sys/compat/sys/siginfo.h Tue Oct 15 18:32:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: siginfo.h,v 1.7 2019/06/30 08:49:21 martin Exp $ */
+/* $NetBSD: siginfo.h,v 1.7.2.1 2019/10/15 18:32:13 martin Exp $ */
/*-
* Copyright (c) 2002 The NetBSD Foundation, Inc.
@@ -75,6 +75,14 @@ struct __ksiginfo32 {
int _error;
uint64_t _args[8]; /* SYS_MAXSYSARGS */
} _syscall;
+
+ struct {
+ int _pe_report_event;
+ union {
+ pid_t _pe_other_pid;
+ lwpid_t _pe_lwp;
+ } _option;
+ } _ptrace_state;
} _reason;
};
Index: src/sys/kern/kern_exec.c
diff -u src/sys/kern/kern_exec.c:1.478 src/sys/kern/kern_exec.c:1.478.2.1
--- src/sys/kern/kern_exec.c:1.478 Fri Jul 5 17:14:48 2019
+++ src/sys/kern/kern_exec.c Tue Oct 15 18:32:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_exec.c,v 1.478 2019/07/05 17:14:48 maxv Exp $ */
+/* $NetBSD: kern_exec.c,v 1.478.2.1 2019/10/15 18:32:13 martin Exp $ */
/*-
* Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -59,7 +59,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_exec.c,v 1.478 2019/07/05 17:14:48 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_exec.c,v 1.478.2.1 2019/10/15 18:32:13 martin Exp $");
#include "opt_exec.h"
#include "opt_execfmt.h"
@@ -1285,7 +1285,7 @@ execve_runproc(struct lwp *l, struct exe
/* posix_spawn(3) reports a single event with implied exec(3) */
if ((p->p_slflag & PSL_TRACED) && !is_spawn) {
mutex_enter(p->p_lock);
- eventswitch(TRAP_EXEC);
+ eventswitch(TRAP_EXEC, 0, 0);
mutex_enter(proc_lock);
}
@@ -2197,7 +2197,7 @@ spawn_return(void *arg)
}
mutex_enter(p->p_lock);
- eventswitch(TRAP_CHLD);
+ eventswitch(TRAP_CHLD, PTRACE_POSIX_SPAWN, p->p_opptr->p_pid);
}
cpu_return:
@@ -2578,8 +2578,6 @@ 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);
- p1->p_pspid = p2->p_pid;
- p2->p_pspid = p1->p_pid;
}
LIST_INSERT_AFTER(p1, p2, p_pglist);
@@ -2633,7 +2631,7 @@ do_posix_spawn(struct lwp *l1, pid_t *pi
}
mutex_enter(p1->p_lock);
- eventswitch(TRAP_CHLD);
+ eventswitch(TRAP_CHLD, PTRACE_POSIX_SPAWN, pid);
}
return 0;
Index: src/sys/kern/kern_fork.c
diff -u src/sys/kern/kern_fork.c:1.213 src/sys/kern/kern_fork.c:1.213.2.1
--- src/sys/kern/kern_fork.c:1.213 Thu Jun 13 20:20:18 2019
+++ src/sys/kern/kern_fork.c Tue Oct 15 18:32:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_fork.c,v 1.213 2019/06/13 20:20:18 kamil Exp $ */
+/* $NetBSD: kern_fork.c,v 1.213.2.1 2019/10/15 18:32:13 martin Exp $ */
/*-
* Copyright (c) 1999, 2001, 2004, 2006, 2007, 2008 The NetBSD Foundation, Inc.
@@ -67,7 +67,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_fork.c,v 1.213 2019/06/13 20:20:18 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_fork.c,v 1.213.2.1 2019/10/15 18:32:13 martin Exp $");
#include "opt_ktrace.h"
#include "opt_dtrace.h"
@@ -252,7 +252,6 @@ fork1(struct lwp *l1, int flags, int exi
int count;
vaddr_t uaddr;
int tnprocs;
- bool trace_fork, trace_vfork;
int error = 0;
p1 = l1->l_proc;
@@ -511,17 +510,8 @@ fork1(struct lwp *l1, int flags, int exi
/*
* Trace fork(2) and vfork(2)-like events on demand in a debugger.
*/
- trace_fork = tracefork(p1, flags);
- trace_vfork = tracevfork(p1, flags);
- if (trace_fork || trace_vfork)
+ if (tracefork(p1, flags) || tracevfork(p1, flags)) {
proc_changeparent(p2, p1->p_pptr);
- if (trace_fork) {
- p1->p_fpid = p2->p_pid;
- p2->p_fpid = p1->p_pid;
- }
- if (trace_vfork) {
- p1->p_vfpid = p2->p_pid;
- p2->p_vfpid = p1->p_pid;
}
LIST_INSERT_AFTER(p1, p2, p_pglist);
@@ -605,7 +595,9 @@ fork1(struct lwp *l1, int flags, int exi
*/
if (tracefork(p1, flags) || tracevfork(p1, flags)) {
mutex_enter(p1->p_lock);
- eventswitch(TRAP_CHLD);
+ eventswitch(TRAP_CHLD,
+ tracefork(p1, flags) ? PTRACE_FORK : PTRACE_VFORK,
+ retval[0]);
mutex_enter(proc_lock);
}
@@ -621,8 +613,7 @@ fork1(struct lwp *l1, int flags, int exi
*/
if (tracevforkdone(p1, flags)) {
mutex_enter(p1->p_lock);
- p1->p_vfpid_done = retval[0];
- eventswitch(TRAP_CHLD);
+ eventswitch(TRAP_CHLD, PTRACE_VFORK_DONE, retval[0]);
} else
mutex_exit(proc_lock);
@@ -645,9 +636,10 @@ child_return(void *arg)
mutex_exit(proc_lock);
goto my_tracer_is_gone;
}
-
mutex_enter(p->p_lock);
- eventswitch(TRAP_CHLD);
+ eventswitch(TRAP_CHLD,
+ ISSET(p->p_lflag, PL_PPWAIT) ? PTRACE_VFORK : PTRACE_FORK,
+ p->p_opptr->p_pid);
}
my_tracer_is_gone:
Index: src/sys/kern/kern_lwp.c
diff -u src/sys/kern/kern_lwp.c:1.202 src/sys/kern/kern_lwp.c:1.202.2.1
--- src/sys/kern/kern_lwp.c:1.202 Tue Jun 4 11:54:03 2019
+++ src/sys/kern/kern_lwp.c Tue Oct 15 18:32:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_lwp.c,v 1.202 2019/06/04 11:54:03 kamil Exp $ */
+/* $NetBSD: kern_lwp.c,v 1.202.2.1 2019/10/15 18:32:13 martin Exp $ */
/*-
* Copyright (c) 2001, 2006, 2007, 2008, 2009 The NetBSD Foundation, Inc.
@@ -211,7 +211,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_lwp.c,v 1.202 2019/06/04 11:54:03 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_lwp.c,v 1.202.2.1 2019/10/15 18:32:13 martin Exp $");
#include "opt_ddb.h"
#include "opt_lockdebug.h"
@@ -239,6 +239,7 @@ __KERNEL_RCSID(0, "$NetBSD: kern_lwp.c,v
#include <sys/fstrans.h>
#include <sys/dtrace_bsd.h>
#include <sys/sdt.h>
+#include <sys/ptrace.h>
#include <sys/xcall.h>
#include <sys/uidinfo.h>
#include <sys/sysctl.h>
@@ -1091,8 +1092,7 @@ lwp_exit(struct lwp *l)
* about a terminating LWP as it would deadlock.
*/
} else {
- p->p_lwp_exited = l->l_lid;
- eventswitch(TRAP_LWP);
+ eventswitch(TRAP_LWP, PTRACE_LWP_EXIT, l->l_lid);
mutex_enter(proc_lock);
}
}
Index: src/sys/kern/kern_sig.c
diff -u src/sys/kern/kern_sig.c:1.364 src/sys/kern/kern_sig.c:1.364.2.1
--- src/sys/kern/kern_sig.c:1.364 Fri Jun 21 04:28:12 2019
+++ src/sys/kern/kern_sig.c Tue Oct 15 18:32:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_sig.c,v 1.364 2019/06/21 04:28:12 kamil Exp $ */
+/* $NetBSD: kern_sig.c,v 1.364.2.1 2019/10/15 18:32:13 martin Exp $ */
/*-
* Copyright (c) 2006, 2007, 2008 The NetBSD Foundation, Inc.
@@ -70,7 +70,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_sig.c,v 1.364 2019/06/21 04:28:12 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_sig.c,v 1.364.2.1 2019/10/15 18:32:13 martin Exp $");
#include "opt_ptrace.h"
#include "opt_dtrace.h"
@@ -1560,7 +1560,7 @@ proc_stop_done(struct proc *p, int ppmas
* an event specific to a traced process only.
*/
void
-eventswitch(int code)
+eventswitch(int code, int pe_report_event, int entity)
{
struct lwp *l = curlwp;
struct proc *p = l->l_proc;
@@ -1605,8 +1605,12 @@ eventswitch(int code)
KSI_INIT_TRAP(&ksi);
ksi.ksi_lid = l->l_lid;
- ksi.ksi_info._signo = signo;
- ksi.ksi_info._code = code;
+ ksi.ksi_signo = signo;
+ ksi.ksi_code = code;
+ ksi.ksi_pe_report_event = pe_report_event;
+
+ CTASSERT(sizeof(ksi.ksi_pe_other_pid) == sizeof(ksi.ksi_pe_lwp));
+ ksi.ksi_pe_other_pid = entity;
/* Needed for ktrace */
ps = p->p_sigacts;
Index: src/sys/kern/sys_lwp.c
diff -u src/sys/kern/sys_lwp.c:1.69 src/sys/kern/sys_lwp.c:1.69.2.1
--- src/sys/kern/sys_lwp.c:1.69 Wed Jul 10 17:52:22 2019
+++ src/sys/kern/sys_lwp.c Tue Oct 15 18:32:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: sys_lwp.c,v 1.69 2019/07/10 17:52:22 maxv Exp $ */
+/* $NetBSD: sys_lwp.c,v 1.69.2.1 2019/10/15 18:32:13 martin Exp $ */
/*-
* Copyright (c) 2001, 2006, 2007, 2008 The NetBSD Foundation, Inc.
@@ -35,7 +35,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_lwp.c,v 1.69 2019/07/10 17:52:22 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_lwp.c,v 1.69.2.1 2019/10/15 18:32:13 martin Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -45,6 +45,7 @@ __KERNEL_RCSID(0, "$NetBSD: sys_lwp.c,v
#include <sys/syscallargs.h>
#include <sys/kauth.h>
#include <sys/kmem.h>
+#include <sys/ptrace.h>
#include <sys/sleepq.h>
#include <sys/lwpctl.h>
#include <sys/cpu.h>
@@ -91,8 +92,7 @@ mi_startlwp(void *arg)
}
mutex_enter(p->p_lock);
- p->p_lwp_created = l->l_lid;
- eventswitch(TRAP_LWP);
+ eventswitch(TRAP_LWP, PTRACE_LWP_CREATE, l->l_lid);
}
}
Index: src/sys/kern/sys_ptrace_common.c
diff -u src/sys/kern/sys_ptrace_common.c:1.58.2.1 src/sys/kern/sys_ptrace_common.c:1.58.2.2
--- src/sys/kern/sys_ptrace_common.c:1.58.2.1 Tue Oct 15 18:21:06 2019
+++ src/sys/kern/sys_ptrace_common.c Tue Oct 15 18:32:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: sys_ptrace_common.c,v 1.58.2.1 2019/10/15 18:21:06 martin Exp $ */
+/* $NetBSD: sys_ptrace_common.c,v 1.58.2.2 2019/10/15 18:32:13 martin 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 1.58.2.1 2019/10/15 18:21:06 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_ptrace_common.c,v 1.58.2.2 2019/10/15 18:32:13 martin Exp $");
#ifdef _KERNEL_OPT
#include "opt_ptrace.h"
@@ -694,27 +694,25 @@ ptrace_get_process_state(struct proc *t,
DPRINTF(("%s: %zu != %zu\n", __func__, data, sizeof(ps)));
return EINVAL;
}
- memset(&ps, 0, sizeof(ps));
- if (t->p_fpid) {
- ps.pe_report_event = PTRACE_FORK;
- ps.pe_other_pid = t->p_fpid;
- } else if (t->p_vfpid) {
- ps.pe_report_event = PTRACE_VFORK;
- ps.pe_other_pid = t->p_vfpid;
- } else if (t->p_vfpid_done) {
- ps.pe_report_event = PTRACE_VFORK_DONE;
- ps.pe_other_pid = t->p_vfpid_done;
- } else if (t->p_lwp_created) {
- ps.pe_report_event = PTRACE_LWP_CREATE;
- ps.pe_lwp = t->p_lwp_created;
- } else if (t->p_lwp_exited) {
- ps.pe_report_event = PTRACE_LWP_EXIT;
- ps.pe_lwp = t->p_lwp_exited;
- } else if (t->p_pspid) {
- ps.pe_report_event = PTRACE_POSIX_SPAWN;
- ps.pe_other_pid = t->p_pspid;
+ if (t->p_sigctx.ps_info._signo != SIGTRAP ||
+ (t->p_sigctx.ps_info._code != TRAP_CHLD &&
+ t->p_sigctx.ps_info._code != TRAP_LWP)) {
+ return EINVAL;
}
+
+ ps.pe_report_event =
+ t->p_sigctx.ps_info._reason._ptrace_state._pe_report_event;
+
+ CTASSERT(sizeof(ps.pe_other_pid) ==
+ sizeof(t->p_sigctx.ps_info._reason._ptrace_state._option._pe_other_pid));
+ CTASSERT(sizeof(ps.pe_lwp) ==
+ sizeof(t->p_sigctx.ps_info._reason._ptrace_state._option._pe_other_pid));
+ CTASSERT(sizeof(ps.pe_other_pid) == sizeof(ps.pe_lwp));
+
+ ps.pe_other_pid =
+ t->p_sigctx.ps_info._reason._ptrace_state._option._pe_other_pid;
+
DPRINTF(("%s: lwp=%d event=%#x pid=%d lwp=%d\n", __func__,
t->p_sigctx.ps_lwp, ps.pe_report_event,
ps.pe_other_pid, ps.pe_lwp));
@@ -894,13 +892,6 @@ ptrace_sendsig(struct proc *t, struct lw
{
ksiginfo_t ksi;
- t->p_fpid = 0;
- t->p_vfpid = 0;
- t->p_vfpid_done = 0;
- t->p_lwp_created = 0;
- t->p_lwp_exited = 0;
- t->p_pspid = 0;
-
/* Finally, deliver the requested signal (or none). */
if (t->p_stat == SSTOP) {
/*
Index: src/sys/sys/siginfo.h
diff -u src/sys/sys/siginfo.h:1.33 src/sys/sys/siginfo.h:1.33.2.1
--- src/sys/sys/siginfo.h:1.33 Mon May 6 08:05:03 2019
+++ src/sys/sys/siginfo.h Tue Oct 15 18:32:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: siginfo.h,v 1.33 2019/05/06 08:05:03 kamil Exp $ */
+/* $NetBSD: siginfo.h,v 1.33.2.1 2019/10/15 18:32:13 martin Exp $ */
/*-
* Copyright (c) 2002 The NetBSD Foundation, Inc.
@@ -84,6 +84,14 @@ struct _ksiginfo {
int _error;
uint64_t _args[8]; /* SYS_MAXSYSARGS */
} _syscall;
+
+ struct {
+ int _pe_report_event;
+ union {
+ pid_t _pe_other_pid;
+ lwpid_t _pe_lwp;
+ } _option;
+ } _ptrace_state;
} _reason;
};
@@ -167,6 +175,10 @@ typedef union siginfo {
#define si_error _info._reason._syscall._error
#define si_args _info._reason._syscall._args
+#define si_pe_report_event _info._reason._ptrace_state._pe_report_event
+#define si_pe_other_pid _info._reason._ptrace_state._option._pe_other_pid
+#define si_pe_lwp _info._reason._ptrace_state._option._pe_lwp
+
#ifdef _KERNEL
/** Field access macros */
#define ksi_signo ksi_info._signo
@@ -192,6 +204,10 @@ typedef union siginfo {
#define ksi_retval ksi_info._reason._syscall._retval
#define ksi_error ksi_info._reason._syscall._error
#define ksi_args ksi_info._reason._syscall._args
+
+#define ksi_pe_report_event ksi_info._reason._ptrace_state._pe_report_event
+#define ksi_pe_other_pid ksi_info._reason._ptrace_state._option._pe_other_pid
+#define ksi_pe_lwp ksi_info._reason._ptrace_state._option._pe_lwp
#endif /* _KERNEL */
/** si_code */
Index: src/sys/sys/signalvar.h
diff -u src/sys/sys/signalvar.h:1.93 src/sys/sys/signalvar.h:1.93.2.1
--- src/sys/sys/signalvar.h:1.93 Fri May 3 22:34:21 2019
+++ src/sys/sys/signalvar.h Tue Oct 15 18:32:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: signalvar.h,v 1.93 2019/05/03 22:34:21 kamil Exp $ */
+/* $NetBSD: signalvar.h,v 1.93.2.1 2019/10/15 18:32:13 martin Exp $ */
/*
* Copyright (c) 1991, 1993
@@ -136,7 +136,7 @@ void killproc(struct proc *, const char
void setsigvec(struct proc *, int, struct sigaction *);
int killpg1(struct lwp *, struct ksiginfo *, int, int);
void proc_unstop(struct proc *p);
-void eventswitch(int);
+void eventswitch(int, int, int);
void sigswitch(int, int, bool);
