From owner-svn-src-all@freebsd.org Tue Feb 21 23:46:01 2017 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 91E9CCE85C6; Tue, 21 Feb 2017 23:46:01 +0000 (UTC) (envelope-from rpokala@mac.com) Received: from mr11p00im-asmtp004.me.com (mr11p00im-asmtp004.me.com [17.110.69.135]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 75FBF1CB4; Tue, 21 Feb 2017 23:46:01 +0000 (UTC) (envelope-from rpokala@mac.com) Received: from process-dkim-sign-daemon.mr11p00im-asmtp004.me.com by mr11p00im-asmtp004.me.com (Oracle Communications Messaging Server 7.0.5.38.0 64bit (built Feb 26 2016)) id <0OLQ00G00YQ4PD00@mr11p00im-asmtp004.me.com>; Tue, 21 Feb 2017 23:45:45 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mac.com; s=4d515a; t=1487720745; bh=5KnarRJjm3iR1Vm/KUiGRo0Iv5Vns7k3HYyIYBiaH4o=; h=Date:Subject:From:To:Message-id:MIME-version:Content-type; b=fORB4xiEemibaahkFGZfRWvvZ/+zTYp0Ox4466EfOF8oM5onCjp73uY1Kudp0b8nX aK2xZUMTuFpliX4WHBwZOawI1ufbkUgZ7eTF4l8TPYE+7L8FP1jUokOILmrcJQJ2bn FpQtJHuBlNp0DT7l+Nsu++dmPggyOfPY2F3bgAfpy44o3wkTY92u6Czc6SvscwfVww vZZYw4a5vw+BDFxkZjw+3t+7NpJLCY+jAeOAMeypKyv53FFnazbDHKCenIG8pTyQSX u8cJlJw3KjEC4ATC0Fjqo13VU1av5kyqsP0puwzTyxzYBminxM+LZOKtxBssEo/3SU Zmuwg14cbSSCA== Received: from icloud.com ([127.0.0.1]) by mr11p00im-asmtp004.me.com (Oracle Communications Messaging Server 7.0.5.38.0 64bit (built Feb 26 2016)) with ESMTPSA id <0OLR00CEV0O7CU20@mr11p00im-asmtp004.me.com>; Tue, 21 Feb 2017 23:45:44 +0000 (GMT) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-02-21_21:,, signatures=0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 clxscore=1034 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1701120000 definitions=main-1702210219 User-Agent: Microsoft-MacOutlook/f.1f.0.170216 Date: Tue, 21 Feb 2017 15:45:42 -0800 Subject: Re: svn commit: r313992 - in head: sys/kern sys/sys tests/sys/kern From: Ravi Pokala Sender: "Pokala, Ravi" To: Eric Badger , src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Message-id: <69055A2F-849B-496B-94BE-0724E0957B81@panasas.com> Thread-topic: svn commit: r313992 - in head: sys/kern sys/sys tests/sys/kern References: <201702201553.v1KFrGqx057871@repo.freebsd.org> In-reply-to: <201702201553.v1KFrGqx057871@repo.freebsd.org> MIME-version: 1.0 Content-type: text/plain; charset=UTF-8 Content-transfer-encoding: 7bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 21 Feb 2017 23:46:01 -0000 Hi Eric, This appears to break buildworld for a bunch of platforms -- possibly all the ones that use gcc rather than clang? A representative example from sparc64: /usr/home/rpokala/freebsd/clean/base/head/tests/sys/kern/ptrace_test.c: In function 'atfu_ptrace__PT_KILL_breakpoint_body': /usr/home/rpokala/freebsd/clean/base/head/tests/sys/kern/ptrace_test.c:1693: warning: implicit declaration of function '__builtin_debugtrap' *** [ptrace_test.o] Error code 1 Thanks, Ravi (rpokala@) -----Original Message----- From: on behalf of Eric Badger Date: 2017-02-20, Monday at 07:53 To: , , Subject: svn commit: r313992 - in head: sys/kern sys/sys tests/sys/kern Author: badger Date: Mon Feb 20 15:53:16 2017 New Revision: 313992 URL: https://svnweb.freebsd.org/changeset/base/313992 Log: Defer ptracestop() signals that cannot be delivered immediately When a thread is stopped in ptracestop(), the ptrace(2) user may request a signal be delivered upon resumption of the thread. Heretofore, those signals were discarded unless ptracestop()'s caller was issignal(). Fix this by modifying ptracestop() to queue up signals requested by the ptrace user that will be delivered when possible. Take special care when the signal is SIGKILL (usually generated from a PT_KILL request); no new stop events should be triggered after a PT_KILL. Add a number of tests for the new functionality. Several tests were authored by jhb. PR: 212607 Reviewed by: kib Approved by: kib (mentor) MFC after: 2 weeks Sponsored by: Dell EMC In collaboration with: jhb Differential Revision: https://reviews.freebsd.org/D9260 Modified: head/sys/kern/kern_fork.c head/sys/kern/kern_sig.c head/sys/kern/kern_thr.c head/sys/kern/subr_syscall.c head/sys/kern/sys_process.c head/sys/sys/signalvar.h head/tests/sys/kern/Makefile head/tests/sys/kern/ptrace_test.c Modified: head/sys/kern/kern_fork.c ============================================================================== --- head/sys/kern/kern_fork.c Mon Feb 20 10:51:46 2017 (r313991) +++ head/sys/kern/kern_fork.c Mon Feb 20 15:53:16 2017 (r313992) @@ -1081,7 +1081,7 @@ fork_return(struct thread *td, struct tr proc_reparent(p, dbg); sx_xunlock(&proctree_lock); td->td_dbgflags |= TDB_CHILD | TDB_SCX | TDB_FSTP; - ptracestop(td, SIGSTOP); + ptracestop(td, SIGSTOP, NULL); td->td_dbgflags &= ~(TDB_CHILD | TDB_SCX); } else { /* @@ -1102,7 +1102,7 @@ fork_return(struct thread *td, struct tr _STOPEVENT(p, S_SCX, td->td_dbg_sc_code); if ((p->p_ptevents & PTRACE_SCX) != 0 || (td->td_dbgflags & TDB_BORN) != 0) - ptracestop(td, SIGTRAP); + ptracestop(td, SIGTRAP, NULL); td->td_dbgflags &= ~(TDB_SCX | TDB_BORN); PROC_UNLOCK(p); } Modified: head/sys/kern/kern_sig.c ============================================================================== --- head/sys/kern/kern_sig.c Mon Feb 20 10:51:46 2017 (r313991) +++ head/sys/kern/kern_sig.c Mon Feb 20 15:53:16 2017 (r313992) @@ -278,6 +278,7 @@ sigqueue_init(sigqueue_t *list, struct p { SIGEMPTYSET(list->sq_signals); SIGEMPTYSET(list->sq_kill); + SIGEMPTYSET(list->sq_ptrace); TAILQ_INIT(&list->sq_list); list->sq_proc = p; list->sq_flags = SQ_INIT; @@ -301,9 +302,15 @@ sigqueue_get(sigqueue_t *sq, int signo, if (!SIGISMEMBER(sq->sq_signals, signo)) return (0); + if (SIGISMEMBER(sq->sq_ptrace, signo)) { + count++; + SIGDELSET(sq->sq_ptrace, signo); + si->ksi_flags |= KSI_PTRACE; + } if (SIGISMEMBER(sq->sq_kill, signo)) { count++; - SIGDELSET(sq->sq_kill, signo); + if (count == 1) + SIGDELSET(sq->sq_kill, signo); } TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) { @@ -347,7 +354,8 @@ sigqueue_take(ksiginfo_t *ksi) if (kp->ksi_signo == ksi->ksi_signo) break; } - if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo)) + if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo) && + !SIGISMEMBER(sq->sq_ptrace, ksi->ksi_signo)) SIGDELSET(sq->sq_signals, ksi->ksi_signo); } @@ -360,6 +368,10 @@ sigqueue_add(sigqueue_t *sq, int signo, KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited")); + /* + * SIGKILL/SIGSTOP cannot be caught or masked, so take the fast path + * for these signals. + */ if (signo == SIGKILL || signo == SIGSTOP || si == NULL) { SIGADDSET(sq->sq_kill, signo); goto out_set_bit; @@ -398,16 +410,19 @@ sigqueue_add(sigqueue_t *sq, int signo, ksi->ksi_sigq = sq; } - if ((si->ksi_flags & KSI_TRAP) != 0 || - (si->ksi_flags & KSI_SIGQ) == 0) { - if (ret != 0) + if (ret != 0) { + if ((si->ksi_flags & KSI_PTRACE) != 0) { + SIGADDSET(sq->sq_ptrace, signo); + ret = 0; + goto out_set_bit; + } else if ((si->ksi_flags & KSI_TRAP) != 0 || + (si->ksi_flags & KSI_SIGQ) == 0) { SIGADDSET(sq->sq_kill, signo); - ret = 0; - goto out_set_bit; - } - - if (ret != 0) + ret = 0; + goto out_set_bit; + } return (ret); + } out_set_bit: SIGADDSET(sq->sq_signals, signo); @@ -434,6 +449,7 @@ sigqueue_flush(sigqueue_t *sq) SIGEMPTYSET(sq->sq_signals); SIGEMPTYSET(sq->sq_kill); + SIGEMPTYSET(sq->sq_ptrace); } static void @@ -466,6 +482,11 @@ sigqueue_move_set(sigqueue_t *src, sigqu SIGSETOR(dst->sq_kill, tmp); SIGSETNAND(src->sq_kill, tmp); + tmp = src->sq_ptrace; + SIGSETAND(tmp, *set); + SIGSETOR(dst->sq_ptrace, tmp); + SIGSETNAND(src->sq_ptrace, tmp); + tmp = src->sq_signals; SIGSETAND(tmp, *set); SIGSETOR(dst->sq_signals, tmp); @@ -502,6 +523,7 @@ sigqueue_delete_set(sigqueue_t *sq, cons } } SIGSETNAND(sq->sq_kill, *set); + SIGSETNAND(sq->sq_ptrace, *set); SIGSETNAND(sq->sq_signals, *set); } @@ -2500,69 +2522,116 @@ sig_suspend_threads(struct thread *td, s return (wakeup_swapper); } +/* + * Stop the process for an event deemed interesting to the debugger. If si is + * non-NULL, this is a signal exchange; the new signal requested by the + * debugger will be returned for handling. If si is NULL, this is some other + * type of interesting event. The debugger may request a signal be delivered in + * that case as well, however it will be deferred until it can be handled. + */ int -ptracestop(struct thread *td, int sig) +ptracestop(struct thread *td, int sig, ksiginfo_t *si) { struct proc *p = td->td_proc; + struct thread *td2; + ksiginfo_t ksi; + int prop; PROC_LOCK_ASSERT(p, MA_OWNED); KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process")); WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, &p->p_mtx.lock_object, "Stopping for traced signal"); - td->td_dbgflags |= TDB_XSIG; td->td_xsig = sig; - CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d", - td->td_tid, p->p_pid, td->td_dbgflags, sig); - PROC_SLOCK(p); - while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) { - if (p->p_flag & P_SINGLE_EXIT && - !(td->td_dbgflags & TDB_EXIT)) { + + if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) { + td->td_dbgflags |= TDB_XSIG; + CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d", + td->td_tid, p->p_pid, td->td_dbgflags, sig); + PROC_SLOCK(p); + while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) { + if (P_KILLED(p)) { + /* + * Ensure that, if we've been PT_KILLed, the + * exit status reflects that. Another thread + * may also be in ptracestop(), having just + * received the SIGKILL, but this thread was + * unsuspended first. + */ + td->td_dbgflags &= ~TDB_XSIG; + td->td_xsig = SIGKILL; + p->p_ptevents = 0; + break; + } + if (p->p_flag & P_SINGLE_EXIT && + !(td->td_dbgflags & TDB_EXIT)) { + /* + * Ignore ptrace stops except for thread exit + * events when the process exits. + */ + td->td_dbgflags &= ~TDB_XSIG; + PROC_SUNLOCK(p); + return (0); + } + /* - * Ignore ptrace stops except for thread exit - * events when the process exits. + * Make wait(2) work. Ensure that right after the + * attach, the thread which was decided to become the + * leader of attach gets reported to the waiter. + * Otherwise, just avoid overwriting another thread's + * assignment to p_xthread. If another thread has + * already set p_xthread, the current thread will get + * a chance to report itself upon the next iteration. */ - td->td_dbgflags &= ~TDB_XSIG; - PROC_SUNLOCK(p); - return (sig); - } - - /* - * Make wait(2) work. Ensure that right after the - * attach, the thread which was decided to become the - * leader of attach gets reported to the waiter. - * Otherwise, just avoid overwriting another thread's - * assignment to p_xthread. If another thread has - * already set p_xthread, the current thread will get - * a chance to report itself upon the next iteration. - */ - if ((td->td_dbgflags & TDB_FSTP) != 0 || - ((p->p_flag2 & P2_PTRACE_FSTP) == 0 && - p->p_xthread == NULL)) { - p->p_xsig = sig; - p->p_xthread = td; - td->td_dbgflags &= ~TDB_FSTP; - p->p_flag2 &= ~P2_PTRACE_FSTP; - p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE; - sig_suspend_threads(td, p, 0); - } - if ((td->td_dbgflags & TDB_STOPATFORK) != 0) { - td->td_dbgflags &= ~TDB_STOPATFORK; - cv_broadcast(&p->p_dbgwait); - } + if ((td->td_dbgflags & TDB_FSTP) != 0 || + ((p->p_flag2 & P2_PTRACE_FSTP) == 0 && + p->p_xthread == NULL)) { + p->p_xsig = sig; + p->p_xthread = td; + td->td_dbgflags &= ~TDB_FSTP; + p->p_flag2 &= ~P2_PTRACE_FSTP; + p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE; + sig_suspend_threads(td, p, 0); + } + if ((td->td_dbgflags & TDB_STOPATFORK) != 0) { + td->td_dbgflags &= ~TDB_STOPATFORK; + cv_broadcast(&p->p_dbgwait); + } stopme: - thread_suspend_switch(td, p); - if (p->p_xthread == td) - p->p_xthread = NULL; - if (!(p->p_flag & P_TRACED)) - break; - if (td->td_dbgflags & TDB_SUSPEND) { - if (p->p_flag & P_SINGLE_EXIT) + thread_suspend_switch(td, p); + if (p->p_xthread == td) + p->p_xthread = NULL; + if (!(p->p_flag & P_TRACED)) break; - goto stopme; + if (td->td_dbgflags & TDB_SUSPEND) { + if (p->p_flag & P_SINGLE_EXIT) + break; + goto stopme; + } } + PROC_SUNLOCK(p); } - PROC_SUNLOCK(p); + + if (si != NULL && sig == td->td_xsig) { + /* Parent wants us to take the original signal unchanged. */ + si->ksi_flags |= KSI_HEAD; + if (sigqueue_add(&td->td_sigqueue, sig, si) != 0) + si->ksi_signo = 0; + } else if (td->td_xsig != 0) { + /* + * If parent wants us to take a new signal, then it will leave + * it in td->td_xsig; otherwise we just look for signals again. + */ + ksiginfo_init(&ksi); + ksi.ksi_signo = td->td_xsig; + ksi.ksi_flags |= KSI_PTRACE; + prop = sigprop(td->td_xsig); + td2 = sigtd(p, td->td_xsig, prop); + tdsendsignal(p, td2, td->td_xsig, &ksi); + if (td != td2) + return (0); + } + return (td->td_xsig); } @@ -2720,7 +2789,7 @@ issignal(struct thread *td) struct sigacts *ps; struct sigqueue *queue; sigset_t sigpending; - int sig, prop, newsig; + int sig, prop; p = td->td_proc; ps = p->p_sigacts; @@ -2783,47 +2852,18 @@ issignal(struct thread *td) } mtx_unlock(&ps->ps_mtx); - newsig = ptracestop(td, sig); + sig = ptracestop(td, sig, &td->td_dbgksi); mtx_lock(&ps->ps_mtx); - if (sig != newsig) { - - /* - * If parent wants us to take the signal, - * then it will leave it in p->p_xsig; - * otherwise we just look for signals again. - */ - if (newsig == 0) - continue; - sig = newsig; - - /* - * Put the new signal into td_sigqueue. If the - * signal is being masked, look for other - * signals. - */ - sigqueue_add(queue, sig, NULL); - if (SIGISMEMBER(td->td_sigmask, sig)) - continue; - signotify(td); - } else { - if (td->td_dbgksi.ksi_signo != 0) { - td->td_dbgksi.ksi_flags |= KSI_HEAD; - if (sigqueue_add(&td->td_sigqueue, sig, - &td->td_dbgksi) != 0) - td->td_dbgksi.ksi_signo = 0; - } - if (td->td_dbgksi.ksi_signo == 0) - sigqueue_add(&td->td_sigqueue, sig, - NULL); - } - - /* + /* + * Keep looking if the debugger discarded the signal + * or replaced it with a masked signal. + * * If the traced bit got turned off, go back up * to the top to rescan signals. This ensures * that p_sig* and p_sigact are consistent. */ - if ((p->p_flag & P_TRACED) == 0) + if (sig == 0 || (p->p_flag & P_TRACED) == 0) continue; } Modified: head/sys/kern/kern_thr.c ============================================================================== --- head/sys/kern/kern_thr.c Mon Feb 20 10:51:46 2017 (r313991) +++ head/sys/kern/kern_thr.c Mon Feb 20 15:53:16 2017 (r313992) @@ -356,7 +356,7 @@ kern_thr_exit(struct thread *td) p->p_pendingexits++; td->td_dbgflags |= TDB_EXIT; if (p->p_ptevents & PTRACE_LWP) - ptracestop(td, SIGTRAP); + ptracestop(td, SIGTRAP, NULL); PROC_UNLOCK(p); tidhash_remove(td); PROC_LOCK(p); Modified: head/sys/kern/subr_syscall.c ============================================================================== --- head/sys/kern/subr_syscall.c Mon Feb 20 10:51:46 2017 (r313991) +++ head/sys/kern/subr_syscall.c Mon Feb 20 15:53:16 2017 (r313992) @@ -88,7 +88,7 @@ syscallenter(struct thread *td, struct s td->td_dbg_sc_code = sa->code; td->td_dbg_sc_narg = sa->narg; if (p->p_ptevents & PTRACE_SCE) - ptracestop((td), SIGTRAP); + ptracestop((td), SIGTRAP, NULL); PROC_UNLOCK(p); } if (td->td_dbgflags & TDB_USERWR) { @@ -222,7 +222,7 @@ syscallret(struct thread *td, int error, if (traced && ((td->td_dbgflags & (TDB_FORK | TDB_EXEC)) != 0 || (p->p_ptevents & PTRACE_SCX) != 0)) - ptracestop(td, SIGTRAP); + ptracestop(td, SIGTRAP, NULL); td->td_dbgflags &= ~(TDB_SCX | TDB_EXEC | TDB_FORK); PROC_UNLOCK(p); } @@ -259,7 +259,7 @@ again: if (td->td_dbgflags & TDB_VFORK) { PROC_LOCK(p); if (p->p_ptevents & PTRACE_VFORK) - ptracestop(td, SIGTRAP); + ptracestop(td, SIGTRAP, NULL); td->td_dbgflags &= ~TDB_VFORK; PROC_UNLOCK(p); } Modified: head/sys/kern/sys_process.c ============================================================================== --- head/sys/kern/sys_process.c Mon Feb 20 10:51:46 2017 (r313991) +++ head/sys/kern/sys_process.c Mon Feb 20 15:53:16 2017 (r313992) @@ -1125,6 +1125,16 @@ kern_ptrace(struct thread *td, int req, td2->td_dbgflags &= ~TDB_XSIG; td2->td_xsig = data; + /* + * P_WKILLED is insurance that a PT_KILL/SIGKILL always + * works immediately, even if another thread is + * unsuspended first and attempts to handle a different + * signal or if the POSIX.1b style signal queue cannot + * accommodate any new signals. + */ + if (data == SIGKILL) + p->p_flag |= P_WKILLED; + if (req == PT_DETACH) { FOREACH_THREAD_IN_PROC(p, td3) td3->td_dbgflags &= ~TDB_SUSPEND; Modified: head/sys/sys/signalvar.h ============================================================================== --- head/sys/sys/signalvar.h Mon Feb 20 10:51:46 2017 (r313991) +++ head/sys/sys/signalvar.h Mon Feb 20 15:53:16 2017 (r313992) @@ -237,13 +237,15 @@ typedef struct ksiginfo { #define KSI_INS 0x04 /* Directly insert ksi, not the copy */ #define KSI_SIGQ 0x08 /* Generated by sigqueue, might ret EGAIN. */ #define KSI_HEAD 0x10 /* Insert into head, not tail. */ -#define KSI_COPYMASK (KSI_TRAP|KSI_SIGQ) +#define KSI_PTRACE 0x20 /* Generated by ptrace. */ +#define KSI_COPYMASK (KSI_TRAP | KSI_SIGQ | KSI_PTRACE) #define KSI_ONQ(ksi) ((ksi)->ksi_sigq != NULL) typedef struct sigqueue { sigset_t sq_signals; /* All pending signals. */ sigset_t sq_kill; /* Legacy depth 1 queue. */ + sigset_t sq_ptrace; /* Depth 1 queue for ptrace(2). */ TAILQ_HEAD(, ksiginfo) sq_list;/* Queued signal info. */ struct proc *sq_proc; int sq_flags; @@ -370,7 +372,7 @@ void pgsigio(struct sigio **sigiop, int void pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi); int postsig(int sig); void kern_psignal(struct proc *p, int sig); -int ptracestop(struct thread *td, int sig); +int ptracestop(struct thread *td, int sig, ksiginfo_t *si); void sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *retmask); struct sigacts *sigacts_alloc(void); void sigacts_copy(struct sigacts *dest, struct sigacts *src); Modified: head/tests/sys/kern/Makefile ============================================================================== --- head/tests/sys/kern/Makefile Mon Feb 20 10:51:46 2017 (r313991) +++ head/tests/sys/kern/Makefile Mon Feb 20 15:53:16 2017 (r313992) @@ -8,6 +8,7 @@ TESTSDIR= ${TESTSBASE}/sys/kern ATF_TESTS_C+= kern_copyin ATF_TESTS_C+= kern_descrip_test ATF_TESTS_C+= ptrace_test +TEST_METADATA.ptrace_test+= timeout="15" ATF_TESTS_C+= reaper PLAIN_TESTS_C+= subr_unit_test ATF_TESTS_C+= unix_seqpacket_test Modified: head/tests/sys/kern/ptrace_test.c ============================================================================== --- head/tests/sys/kern/ptrace_test.c Mon Feb 20 10:51:46 2017 (r313991) +++ head/tests/sys/kern/ptrace_test.c Mon Feb 20 15:53:16 2017 (r313992) @@ -28,6 +28,9 @@ __FBSDID("$FreeBSD$"); #include +#include +#include +#include #include #include #include @@ -35,6 +38,7 @@ __FBSDID("$FreeBSD$"); #include #include #include +#include #include #include #include @@ -1673,6 +1677,1107 @@ ATF_TC_BODY(ptrace__ptrace_vfork_follow, ATF_REQUIRE(errno == ECHILD); } +/* + * Verify that no more events are reported after PT_KILL except for the + * process exit when stopped due to a breakpoint trap. + */ +ATF_TC_WITHOUT_HEAD(ptrace__PT_KILL_breakpoint); +ATF_TC_BODY(ptrace__PT_KILL_breakpoint, tc) +{ + pid_t fpid, wpid; + int status; + + ATF_REQUIRE((fpid = fork()) != -1); + if (fpid == 0) { + trace_me(); + __builtin_debugtrap(); + exit(1); + } + + /* The first wait() should report the stop from SIGSTOP. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGSTOP); + + /* Continue the child ignoring the SIGSTOP. */ + ATF_REQUIRE(ptrace(PT_CONTINUE, fpid, (caddr_t)1, 0) == 0); + + /* The second wait() should report hitting the breakpoint. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGTRAP); + + /* Kill the child process. */ + ATF_REQUIRE(ptrace(PT_KILL, fpid, 0, 0) == 0); + + /* The last wait() should report the SIGKILL. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSIGNALED(status)); + ATF_REQUIRE(WTERMSIG(status) == SIGKILL); + + wpid = wait(&status); + ATF_REQUIRE(wpid == -1); + ATF_REQUIRE(errno == ECHILD); +} + +/* + * Verify that no more events are reported after PT_KILL except for the + * process exit when stopped inside of a system call. + */ +ATF_TC_WITHOUT_HEAD(ptrace__PT_KILL_system_call); +ATF_TC_BODY(ptrace__PT_KILL_system_call, tc) +{ + struct ptrace_lwpinfo pl; + pid_t fpid, wpid; + int status; + + ATF_REQUIRE((fpid = fork()) != -1); + if (fpid == 0) { + trace_me(); + getpid(); + exit(1); + } + + /* The first wait() should report the stop from SIGSTOP. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGSTOP); + + /* Continue the child ignoring the SIGSTOP and tracing system calls. */ + ATF_REQUIRE(ptrace(PT_SYSCALL, fpid, (caddr_t)1, 0) == 0); + + /* The second wait() should report a system call entry for getpid(). */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGTRAP); + + ATF_REQUIRE(ptrace(PT_LWPINFO, wpid, (caddr_t)&pl, sizeof(pl)) != -1); + ATF_REQUIRE(pl.pl_flags & PL_FLAG_SCE); + + /* Kill the child process. */ + ATF_REQUIRE(ptrace(PT_KILL, fpid, 0, 0) == 0); + + /* The last wait() should report the SIGKILL. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSIGNALED(status)); + ATF_REQUIRE(WTERMSIG(status) == SIGKILL); + + wpid = wait(&status); + ATF_REQUIRE(wpid == -1); + ATF_REQUIRE(errno == ECHILD); +} + +/* + * Verify that no more events are reported after PT_KILL except for the + * process exit when killing a multithreaded process. + */ +ATF_TC_WITHOUT_HEAD(ptrace__PT_KILL_threads); +ATF_TC_BODY(ptrace__PT_KILL_threads, tc) +{ + struct ptrace_lwpinfo pl; + pid_t fpid, wpid; + lwpid_t main_lwp; + int status; + + ATF_REQUIRE((fpid = fork()) != -1); + if (fpid == 0) { + trace_me(); + simple_thread_main(); + } + + /* The first wait() should report the stop from SIGSTOP. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGSTOP); + + ATF_REQUIRE(ptrace(PT_LWPINFO, wpid, (caddr_t)&pl, + sizeof(pl)) != -1); + main_lwp = pl.pl_lwpid; + + ATF_REQUIRE(ptrace(PT_LWP_EVENTS, wpid, NULL, 1) == 0); + + /* Continue the child ignoring the SIGSTOP. */ + ATF_REQUIRE(ptrace(PT_CONTINUE, fpid, (caddr_t)1, 0) == 0); + + /* The first event should be for the child thread's birth. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGTRAP); + + ATF_REQUIRE(ptrace(PT_LWPINFO, wpid, (caddr_t)&pl, sizeof(pl)) != -1); + ATF_REQUIRE((pl.pl_flags & (PL_FLAG_BORN | PL_FLAG_SCX)) == + (PL_FLAG_BORN | PL_FLAG_SCX)); + ATF_REQUIRE(pl.pl_lwpid != main_lwp); + + /* Kill the child process. */ + ATF_REQUIRE(ptrace(PT_KILL, fpid, 0, 0) == 0); + + /* The last wait() should report the SIGKILL. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSIGNALED(status)); + ATF_REQUIRE(WTERMSIG(status) == SIGKILL); + + wpid = wait(&status); + ATF_REQUIRE(wpid == -1); + ATF_REQUIRE(errno == ECHILD); +} + +static void * +mask_usr1_thread(void *arg) +{ + pthread_barrier_t *pbarrier; + sigset_t sigmask; + + pbarrier = (pthread_barrier_t*)arg; + + sigemptyset(&sigmask); + sigaddset(&sigmask, SIGUSR1); + CHILD_REQUIRE(pthread_sigmask(SIG_BLOCK, &sigmask, NULL) == 0); + + /* Sync up with other thread after sigmask updated. */ + pthread_barrier_wait(pbarrier); + + for (;;) + sleep(60); + + return (NULL); +} + +/* + * Verify that the SIGKILL from PT_KILL takes priority over other signals + * and prevents spurious stops due to those other signals. + */ +ATF_TC_WITHOUT_HEAD(ptrace__PT_KILL_competing_signal); +ATF_TC_BODY(ptrace__PT_KILL_competing_signal, tc) +{ + pid_t fpid, wpid; + int status; + cpuset_t setmask; + pthread_t t; + pthread_barrier_t barrier; + + ATF_REQUIRE((fpid = fork()) != -1); + if (fpid == 0) { + /* + * Bind to one CPU so only one thread at a time will run. This + * test expects that the first thread created (the main thread) + * will be unsuspended first and will block the second thread + * from running. + */ + CPU_ZERO(&setmask); + CPU_SET(0, &setmask); + cpusetid_t setid; + CHILD_REQUIRE(cpuset(&setid) == 0); + CHILD_REQUIRE(cpuset_setaffinity(CPU_LEVEL_CPUSET, + CPU_WHICH_CPUSET, setid, sizeof(setmask), &setmask) == 0); + + CHILD_REQUIRE(pthread_barrier_init(&barrier, NULL, 2) == 0); + + CHILD_REQUIRE(pthread_create(&t, NULL, mask_usr1_thread, + (void*)&barrier) == 0); + + sigset_t sigmask; + sigemptyset(&sigmask); + sigaddset(&sigmask, SIGUSR2); + CHILD_REQUIRE(pthread_sigmask(SIG_BLOCK, &sigmask, NULL) == 0); + + /* Sync up with other thread after sigmask updated. */ + pthread_barrier_wait(&barrier); + + trace_me(); + + for (;;) + sleep(60); + + exit(1); + } + + /* The first wait() should report the stop from SIGSTOP. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGSTOP); + + /* Continue the child ignoring the SIGSTOP. */ + ATF_REQUIRE(ptrace(PT_CONTINUE, fpid, (caddr_t)1, 0) == 0); + + /* Send a signal that only the second thread can handle. */ + ATF_REQUIRE(kill(fpid, SIGUSR2) == 0); + + /* The second wait() should report the SIGUSR2. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGUSR2); + + /* Send a signal that only the first thread can handle. */ + ATF_REQUIRE(kill(fpid, SIGUSR1) == 0); + + /* Replace the SIGUSR2 with a kill. */ + ATF_REQUIRE(ptrace(PT_KILL, fpid, 0, 0) == 0); + + /* The last wait() should report the SIGKILL (not the SIGUSR signal). */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSIGNALED(status)); + ATF_REQUIRE(WTERMSIG(status) == SIGKILL); + + wpid = wait(&status); + ATF_REQUIRE(wpid == -1); + ATF_REQUIRE(errno == ECHILD); +} + +/* + * Verify that the SIGKILL from PT_KILL takes priority over other stop events + * and prevents spurious stops caused by those events. + */ +ATF_TC_WITHOUT_HEAD(ptrace__PT_KILL_competing_stop); +ATF_TC_BODY(ptrace__PT_KILL_competing_stop, tc) +{ + pid_t fpid, wpid; + int status, i; + cpuset_t setmask; + pthread_t t; + pthread_barrier_t barrier; + lwpid_t main_lwp; + struct ptrace_lwpinfo pl; + + ATF_REQUIRE((fpid = fork()) != -1); + if (fpid == 0) { + trace_me(); + + /* + * Bind to one CPU so only one thread at a time will run. This + * test expects that the first thread created (the main thread) + * will be unsuspended first and will block the second thread + * from running. + */ + CPU_ZERO(&setmask); + CPU_SET(0, &setmask); + cpusetid_t setid; + CHILD_REQUIRE(cpuset(&setid) == 0); + CHILD_REQUIRE(cpuset_setaffinity(CPU_LEVEL_CPUSET, + CPU_WHICH_CPUSET, setid, sizeof(setmask), &setmask) == 0); + + CHILD_REQUIRE(pthread_barrier_init(&barrier, NULL, 2) == 0); + + CHILD_REQUIRE(pthread_create(&t, NULL, mask_usr1_thread, + (void*)&barrier) == 0); + + sigset_t sigmask; + sigemptyset(&sigmask); + sigaddset(&sigmask, SIGUSR2); + CHILD_REQUIRE(pthread_sigmask(SIG_BLOCK, &sigmask, NULL) == 0); + + /* Sync up with other thread after sigmask updated. */ + pthread_barrier_wait(&barrier); + + /* Sync up with the test before doing the getpid(). */ + raise(SIGSTOP); + + getpid(); + exit(1); + } + + /* The first wait() should report the stop from SIGSTOP. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGSTOP); + + ATF_REQUIRE(ptrace(PT_LWPINFO, wpid, (caddr_t)&pl, sizeof(pl)) != -1); + main_lwp = pl.pl_lwpid; + + /* Continue the child ignoring the SIGSTOP and tracing system calls. */ + ATF_REQUIRE(ptrace(PT_SYSCALL, fpid, (caddr_t)1, 0) == 0); + + /* + * Continue until child is done with setup, which is indicated with + * SIGSTOP. Ignore system calls in the meantime. + */ + for (;;) { + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + if (WSTOPSIG(status) == SIGTRAP) { + ATF_REQUIRE(ptrace(PT_LWPINFO, wpid, (caddr_t)&pl, + sizeof(pl)) != -1); + ATF_REQUIRE(pl.pl_flags & (PL_FLAG_SCE | PL_FLAG_SCX)); + } else { + ATF_REQUIRE(WSTOPSIG(status) == SIGSTOP); + break; + } + ATF_REQUIRE(ptrace(PT_SYSCALL, fpid, (caddr_t)1, 0) == 0); + } + + /* Let both threads hit their syscall entries. */ + for (i = 0; i < 2; ++i) { + ATF_REQUIRE(ptrace(PT_SYSCALL, fpid, (caddr_t)1, 0) == 0); + + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGTRAP); + + ATF_REQUIRE(ptrace(PT_LWPINFO, wpid, (caddr_t)&pl, + sizeof(pl)) != -1); + ATF_REQUIRE(pl.pl_flags & PL_FLAG_SCE); + + /* + * Prevent the main thread from hitting its syscall exit for + * now. + */ + if (pl.pl_lwpid == main_lwp) + ATF_REQUIRE(ptrace(PT_SUSPEND, main_lwp, 0, 0) == 0); + + } + + /* Send a signal that only the second thread can handle. */ + ATF_REQUIRE(kill(fpid, SIGUSR2) == 0); + + ATF_REQUIRE(ptrace(PT_SYSCALL, fpid, (caddr_t)1, 0) == 0); + + /* The second wait() should report the SIGUSR2. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGUSR2); + + /* Allow the main thread to try to finish its system call. */ + ATF_REQUIRE(ptrace(PT_RESUME, main_lwp, 0, 0) == 0); + + /* + * At this point, the main thread is in the middle of a system call and + * has been resumed. The second thread has taken a signal which will be + * replaced with a SIGKILL. We expect the main thread will get to run + * first. It should notice the kill request and exit accordingly and + * not stop for the system call exit event. + */ + + /* Replace the SIGUSR2 with a kill. */ + ATF_REQUIRE(ptrace(PT_KILL, fpid, 0, 0) == 0); + + /* The last wait() should report the SIGKILL (not a syscall exit). */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSIGNALED(status)); + ATF_REQUIRE(WTERMSIG(status) == SIGKILL); + + wpid = wait(&status); + ATF_REQUIRE(wpid == -1); + ATF_REQUIRE(errno == ECHILD); +} + +static void +sigusr1_handler(int sig) +{ + + CHILD_REQUIRE(sig == SIGUSR1); + _exit(2); +} + +/* + * Verify that even if the signal queue is full for a child process, + * a PT_KILL will kill the process. + */ +ATF_TC_WITHOUT_HEAD(ptrace__PT_KILL_with_signal_full_sigqueue); +ATF_TC_BODY(ptrace__PT_KILL_with_signal_full_sigqueue, tc) +{ + pid_t fpid, wpid; + int status; + int max_pending_per_proc; + size_t len; + int i; + + ATF_REQUIRE(signal(SIGUSR1, sigusr1_handler) != SIG_ERR); + + ATF_REQUIRE((fpid = fork()) != -1); + if (fpid == 0) { + trace_me(); + exit(1); + } + + /* The first wait() should report the stop from SIGSTOP. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGSTOP); + + len = sizeof(max_pending_per_proc); + ATF_REQUIRE(sysctlbyname("kern.sigqueue.max_pending_per_proc", + &max_pending_per_proc, &len, NULL, 0) == 0); + + /* Fill the signal queue. */ + for (i = 0; i < max_pending_per_proc; ++i) + ATF_REQUIRE(kill(fpid, SIGUSR1) == 0); + + /* Kill the child process. */ + ATF_REQUIRE(ptrace(PT_KILL, fpid, 0, 0) == 0); + + /* The last wait() should report the SIGKILL. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSIGNALED(status)); + ATF_REQUIRE(WTERMSIG(status) == SIGKILL); + + wpid = wait(&status); + ATF_REQUIRE(wpid == -1); + ATF_REQUIRE(errno == ECHILD); +} + +/* + * Verify that when stopped at a system call entry, a signal can be + * requested with PT_CONTINUE which will be delivered once the system + * call is complete. + */ +ATF_TC_WITHOUT_HEAD(ptrace__PT_CONTINUE_with_signal_system_call_entry); +ATF_TC_BODY(ptrace__PT_CONTINUE_with_signal_system_call_entry, tc) +{ + struct ptrace_lwpinfo pl; + pid_t fpid, wpid; + int status; + + ATF_REQUIRE(signal(SIGUSR1, sigusr1_handler) != SIG_ERR); + + ATF_REQUIRE((fpid = fork()) != -1); + if (fpid == 0) { + trace_me(); + getpid(); + exit(1); + } + + /* The first wait() should report the stop from SIGSTOP. */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGSTOP); + + /* Continue the child ignoring the SIGSTOP and tracing system calls. */ + ATF_REQUIRE(ptrace(PT_SYSCALL, fpid, (caddr_t)1, 0) == 0); + + /* The second wait() should report a system call entry for getpid(). */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + ATF_REQUIRE(WIFSTOPPED(status)); + ATF_REQUIRE(WSTOPSIG(status) == SIGTRAP); + + ATF_REQUIRE(ptrace(PT_LWPINFO, wpid, (caddr_t)&pl, sizeof(pl)) != -1); + ATF_REQUIRE(pl.pl_flags & PL_FLAG_SCE); + + /* Continue the child process with a signal. */ + ATF_REQUIRE(ptrace(PT_CONTINUE, fpid, (caddr_t)1, SIGUSR1) == 0); + + for (;;) { + /* + * The last wait() should report exit 2, i.e., a normal _exit + * from the signal handler. In the meantime, catch and proceed + * past any syscall stops. + */ + wpid = waitpid(fpid, &status, 0); + ATF_REQUIRE(wpid == fpid); + if (WIFSTOPPED(status) && WSTOPSIG(status) == SIGTRAP) { + ATF_REQUIRE(ptrace(PT_LWPINFO, wpid, (caddr_t)&pl, sizeof(pl)) != -1); + ATF_REQUIRE(pl.pl_flags & (PL_FLAG_SCE | PL_FLAG_SCX)); + ATF_REQUIRE(ptrace(PT_CONTINUE, fpid, (caddr_t)1, 0) == 0); + } else { + ATF_REQUIRE(WIFEXITED(status)); + ATF_REQUIRE(WEXITSTATUS(status) == 2); + break; + } + } + + wpid = wait(&status); + ATF_REQUIRE(wpid == -1); + ATF_REQUIRE(errno == ECHILD); +} + +static void +sigusr1_counting_handler(int sig) +{ + static int counter = 0; + *** DIFF OUTPUT TRUNCATED AT 1000 LINES ***