Module Name: src
Committed By: kamil
Date: Sun May 20 03:51:32 UTC 2018
Modified Files:
src/sys/kern: sys_ptrace_common.c
src/tests/lib/libc/sys: t_ptrace_wait.c
Log Message:
Fix and enable traceme_signal_nohandler2 in ATF ptrace(2) tests
traceme_signal_nohandler2 checks emitting SIGSTOP to a traced process
with the PT_CONTINUE operation.
The expected behavior is to simulate a behavior of receiving SIGSTOP,
generating SIGCHLD to its parent (in this case the debugger) and ability
to call wait(2)-like function receiving the stopped child event.
The previous behavior was unstopping the process and it has been adjusted
in the kernel code.
FreeBSD keeps unstopping a process for emitting SIGSTOP.
Linux handles this scenario in the same way as NetBSD now.
While there, implement the missing bits in the userland ATF test for
traceme_signal_nohandler2: receiving and validating 2nd SIGSTOP event and
continuing the process, followed by its normal termination.
Sponsored by <The NetBSD Foundation>
To generate a diff of this commit:
cvs rdiff -u -r1.40 -r1.41 src/sys/kern/sys_ptrace_common.c
cvs rdiff -u -r1.47 -r1.48 src/tests/lib/libc/sys/t_ptrace_wait.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:1.40 src/sys/kern/sys_ptrace_common.c:1.41
--- src/sys/kern/sys_ptrace_common.c:1.40 Tue May 1 16:37:23 2018
+++ src/sys/kern/sys_ptrace_common.c Sun May 20 03:51:31 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: sys_ptrace_common.c,v 1.40 2018/05/01 16:37:23 kamil Exp $ */
+/* $NetBSD: sys_ptrace_common.c,v 1.41 2018/05/20 03:51:31 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 1.40 2018/05/01 16:37:23 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_ptrace_common.c,v 1.41 2018/05/20 03:51:31 kamil Exp $");
#ifdef _KERNEL_OPT
#include "opt_ptrace.h"
@@ -865,7 +865,16 @@ ptrace_sendsig(struct proc *t, struct lw
* an LWP runs to see it.
*/
t->p_xsig = signo;
- if (resume_all)
+
+ /*
+ * signo > 0 check precents a potential panic, as
+ * sigismember(&...,0) is invalid check and signo
+ * can be equal to 0 as a special case of no-signal.
+ */
+ if (signo > 0 && sigismember(&stopsigmask, signo)) {
+ t->p_waited = 0;
+ child_psignal(t, 0);
+ } else if (resume_all)
proc_unstop(t);
else
lwp_unstop(lt);
Index: src/tests/lib/libc/sys/t_ptrace_wait.c
diff -u src/tests/lib/libc/sys/t_ptrace_wait.c:1.47 src/tests/lib/libc/sys/t_ptrace_wait.c:1.48
--- src/tests/lib/libc/sys/t_ptrace_wait.c:1.47 Sat May 19 05:25:21 2018
+++ src/tests/lib/libc/sys/t_ptrace_wait.c Sun May 20 03:51:31 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: t_ptrace_wait.c,v 1.47 2018/05/19 05:25:21 kamil Exp $ */
+/* $NetBSD: t_ptrace_wait.c,v 1.48 2018/05/20 03:51:31 kamil Exp $ */
/*-
* Copyright (c) 2016 The NetBSD Foundation, Inc.
@@ -27,7 +27,7 @@
*/
#include <sys/cdefs.h>
-__RCSID("$NetBSD: t_ptrace_wait.c,v 1.47 2018/05/19 05:25:21 kamil Exp $");
+__RCSID("$NetBSD: t_ptrace_wait.c,v 1.48 2018/05/20 03:51:31 kamil Exp $");
#include <sys/param.h>
#include <sys/types.h>
@@ -299,6 +299,7 @@ traceme_signal_nohandler(int sigsent)
switch (sigsent) {
case SIGCONT:
+ case SIGSTOP:
_exit(exitval);
default:
/* NOTREACHED */
@@ -332,6 +333,30 @@ traceme_signal_nohandler(int sigsent)
TWAIT_REQUIRE_SUCCESS(wpid = TWAIT_GENERIC(child, &status, 0), child);
switch (sigsent) {
+ case SIGSTOP:
+ validate_status_stopped(status, sigsent);
+ DPRINTF("Before calling ptrace(2) with PT_GET_SIGINFO for "
+ "child\n");
+ SYSCALL_REQUIRE(ptrace(PT_GET_SIGINFO, child, &info,
+ sizeof(info)) != -1);
+
+ DPRINTF("Signal traced to lwpid=%d\n", info.psi_lwpid);
+ DPRINTF("Signal properties: si_signo=%#x si_code=%#x "
+ "si_errno=%#x\n",
+ info.psi_siginfo.si_signo, info.psi_siginfo.si_code,
+ info.psi_siginfo.si_errno);
+
+ ATF_REQUIRE_EQ(info.psi_siginfo.si_signo, sigval);
+ ATF_REQUIRE_EQ(info.psi_siginfo.si_code, SI_LWP);
+
+ DPRINTF("Before resuming the child process where it left off "
+ "and with signal %s to be sent\n", strsignal(sigsent));
+ SYSCALL_REQUIRE(ptrace(PT_CONTINUE, child, (void *)1, 0) != -1);
+
+ DPRINTF("Before calling %s() for the child\n", TWAIT_FNAME);
+ TWAIT_REQUIRE_SUCCESS(wpid = TWAIT_GENERIC(child, &status, 0),
+ child);
+ /* FALLTHROUGH */
case SIGCONT:
validate_status_exited(status, exitval);
break;
@@ -360,7 +385,7 @@ ATF_TC_BODY(test, tc) \
}
TRACEME_SIGNAL_NOHANDLER(traceme_signal_nohandler1, SIGKILL) /* non-maskable */
-//TRACEME_SIGNAL_NOHANDLER(traceme_signal_nohandler2, SIGSTOP) /* non-maskable */
+TRACEME_SIGNAL_NOHANDLER(traceme_signal_nohandler2, SIGSTOP) /* non-maskable */
TRACEME_SIGNAL_NOHANDLER(traceme_signal_nohandler3, SIGABRT) /* abort trap */
TRACEME_SIGNAL_NOHANDLER(traceme_signal_nohandler4, SIGHUP) /* hangup */
TRACEME_SIGNAL_NOHANDLER(traceme_signal_nohandler5, SIGCONT) /* continued? */
@@ -7113,7 +7138,7 @@ ATF_TP_ADD_TCS(tp)
ATF_TP_ADD_TC(tp, traceme_sighandler_catch3);
ATF_TP_ADD_TC(tp, traceme_signal_nohandler1);
-// ATF_TP_ADD_TC(tp, traceme_signal_nohandler2); // not yet
+ ATF_TP_ADD_TC(tp, traceme_signal_nohandler2);
ATF_TP_ADD_TC(tp, traceme_signal_nohandler3);
ATF_TP_ADD_TC(tp, traceme_signal_nohandler4);
ATF_TP_ADD_TC(tp, traceme_signal_nohandler5);
