Index: head/sys/kern/kern_exit.c =================================================================== --- head/sys/kern/kern_exit.c (revision 163675) +++ head/sys/kern/kern_exit.c (revision 163676) @@ -1,909 +1,908 @@ /*- * Copyright (c) 1982, 1986, 1989, 1991, 1993 * The Regents of the University of California. All rights reserved. * (c) UNIX System Laboratories, Inc. * All or some portions of this file are derived from material licensed * to the University of California by American Telephone and Telegraph * Co. or Unix System Laboratories, Inc. and are reproduced herein with * the permission of UNIX System Laboratories, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)kern_exit.c 8.7 (Berkeley) 2/12/94 */ #include __FBSDID("$FreeBSD$"); #include "opt_compat.h" #include "opt_ktrace.h" #include "opt_mac.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* for acct_process() function prototype */ #include #include #include #ifdef KTRACE #include #endif #include #include #include #include #include #include #include #include #include /* Required to be non-static for SysVR4 emulator */ MALLOC_DEFINE(M_ZOMBIE, "zombie", "zombie proc status"); /* Hook for NFS teardown procedure. */ void (*nlminfo_release_p)(struct proc *p); /* * exit -- * Death of process. * * MPSAFE */ void sys_exit(struct thread *td, struct sys_exit_args *uap) { exit1(td, W_EXITCODE(uap->rval, 0)); /* NOTREACHED */ } /* * Exit: deallocate address space and other resources, change proc state * to zombie, and unlink proc from allproc and parent's lists. Save exit * status and rusage for wait(). Check for child processes and orphan them. */ void exit1(struct thread *td, int rv) { struct proc *p, *nq, *q; struct tty *tp; struct vnode *ttyvp; struct vnode *vtmp; #ifdef KTRACE struct vnode *tracevp; struct ucred *tracecred; #endif struct plimit *plim; int locked; /* * Drop Giant if caller has it. Eventually we should warn about * being called with Giant held. */ while (mtx_owned(&Giant)) mtx_unlock(&Giant); p = td->td_proc; if (p == initproc) { printf("init died (signal %d, exit %d)\n", WTERMSIG(rv), WEXITSTATUS(rv)); panic("Going nowhere without my init!"); } /* * MUST abort all other threads before proceeding past here. */ PROC_LOCK(p); if (p->p_flag & P_HADTHREADS) { retry: /* * First check if some other thread got here before us.. * if so, act apropriatly, (exit or suspend); */ thread_suspend_check(0); /* * Kill off the other threads. This requires * some co-operation from other parts of the kernel * so it may not be instantaneous. With this state set * any thread entering the kernel from userspace will * thread_exit() in trap(). Any thread attempting to * sleep will return immediately with EINTR or EWOULDBLOCK * which will hopefully force them to back out to userland * freeing resources as they go. Any thread attempting * to return to userland will thread_exit() from userret(). * thread_exit() will unsuspend us when the last of the * other threads exits. * If there is already a thread singler after resumption, * calling thread_single will fail; in that case, we just * re-check all suspension request, the thread should * either be suspended there or exit. */ if (thread_single(SINGLE_EXIT)) goto retry; /* * All other activity in this process is now stopped. * Threading support has been turned off. */ } /* * Wakeup anyone in procfs' PIOCWAIT. They should have a hold * on our vmspace, so we should block below until they have * released their reference to us. Note that if they have * requested S_EXIT stops we will block here until they ack * via PIOCCONT. */ _STOPEVENT(p, S_EXIT, rv); /* * Note that we are exiting and do another wakeup of anyone in * PIOCWAIT in case they aren't listening for S_EXIT stops or * decided to wait again after we told them we are exiting. */ p->p_flag |= P_WEXIT; wakeup(&p->p_stype); /* * Wait for any processes that have a hold on our vmspace to * release their reference. */ while (p->p_lock > 0) msleep(&p->p_lock, &p->p_mtx, PWAIT, "exithold", 0); - PROC_LOCK(p->p_pptr); - sigqueue_take(p->p_ksi); - PROC_UNLOCK(p->p_pptr); - PROC_UNLOCK(p); #ifdef AUDIT /* * The Sun BSM exit token contains two components: an exit status as * passed to exit(), and a return value to indicate what sort of exit * it was. The exit status is WEXITSTATUS(rv), but it's not clear * what the return value is. */ AUDIT_ARG(exit, WEXITSTATUS(rv), 0); AUDIT_SYSCALL_EXIT(0, td); #endif /* Are we a task leader? */ if (p == p->p_leader) { mtx_lock(&ppeers_lock); q = p->p_peers; while (q != NULL) { PROC_LOCK(q); psignal(q, SIGKILL); PROC_UNLOCK(q); q = q->p_peers; } while (p->p_peers != NULL) msleep(p, &ppeers_lock, PWAIT, "exit1", 0); mtx_unlock(&ppeers_lock); } /* * Check if any loadable modules need anything done at process exit. * E.g. SYSV IPC stuff * XXX what if one of these generates an error? */ EVENTHANDLER_INVOKE(process_exit, p); MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage), M_ZOMBIE, M_WAITOK); /* * If parent is waiting for us to exit or exec, * P_PPWAIT is set; we will wakeup the parent below. */ PROC_LOCK(p); stopprofclock(p); p->p_flag &= ~(P_TRACED | P_PPWAIT); /* * Stop the real interval timer. If the handler is currently * executing, prevent it from rearming itself and let it finish. */ if (timevalisset(&p->p_realtimer.it_value) && callout_stop(&p->p_itcallout) == 0) { timevalclear(&p->p_realtimer.it_interval); msleep(&p->p_itcallout, &p->p_mtx, PWAIT, "ritwait", 0); KASSERT(!timevalisset(&p->p_realtimer.it_value), ("realtime timer is still armed")); } PROC_UNLOCK(p); /* * Reset any sigio structures pointing to us as a result of * F_SETOWN with our pid. */ funsetownlst(&p->p_sigiolst); /* * If this process has an nlminfo data area (for lockd), release it */ if (nlminfo_release_p != NULL && p->p_nlminfo != NULL) (*nlminfo_release_p)(p); /* * Close open files and release open-file table. * This may block! */ fdfree(td); /* * If this thread tickled GEOM, we need to wait for the giggling to * stop before we return to userland */ if (td->td_pflags & TDP_GEOM) g_waitidle(); /* * Remove ourself from our leader's peer list and wake our leader. */ mtx_lock(&ppeers_lock); if (p->p_leader->p_peers) { q = p->p_leader; while (q->p_peers != p) q = q->p_peers; q->p_peers = p->p_peers; wakeup(p->p_leader); } mtx_unlock(&ppeers_lock); vmspace_exit(td); mtx_lock(&Giant); /* XXX TTY */ sx_xlock(&proctree_lock); if (SESS_LEADER(p)) { struct session *sp; sp = p->p_session; if (sp->s_ttyvp) { /* * Controlling process. * Signal foreground pgrp, * drain controlling terminal * and revoke access to controlling terminal. */ if (sp->s_ttyp && (sp->s_ttyp->t_session == sp)) { tp = sp->s_ttyp; if (sp->s_ttyp->t_pgrp) { PGRP_LOCK(sp->s_ttyp->t_pgrp); pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1); PGRP_UNLOCK(sp->s_ttyp->t_pgrp); } /* XXX tp should be locked. */ sx_xunlock(&proctree_lock); (void) ttywait(tp); sx_xlock(&proctree_lock); /* * The tty could have been revoked * if we blocked. */ if (sp->s_ttyvp) { ttyvp = sp->s_ttyvp; SESS_LOCK(p->p_session); sp->s_ttyvp = NULL; SESS_UNLOCK(p->p_session); sx_xunlock(&proctree_lock); VOP_LOCK(ttyvp, LK_EXCLUSIVE, td); VOP_REVOKE(ttyvp, REVOKEALL); vput(ttyvp); sx_xlock(&proctree_lock); } } if (sp->s_ttyvp) { ttyvp = sp->s_ttyvp; SESS_LOCK(p->p_session); sp->s_ttyvp = NULL; SESS_UNLOCK(p->p_session); vrele(ttyvp); } /* * s_ttyp is not zero'd; we use this to indicate * that the session once had a controlling terminal. * (for logging and informational purposes) */ } SESS_LOCK(p->p_session); sp->s_leader = NULL; SESS_UNLOCK(p->p_session); } fixjobc(p, p->p_pgrp, 0); sx_xunlock(&proctree_lock); (void)acct_process(td); mtx_unlock(&Giant); #ifdef KTRACE /* * Drain any pending records on the thread and release the trace * file. It might be better if drain-and-clear were atomic. */ ktrprocexit(td); PROC_LOCK(p); mtx_lock(&ktrace_mtx); p->p_traceflag = 0; /* don't trace the vrele() */ tracevp = p->p_tracevp; p->p_tracevp = NULL; tracecred = p->p_tracecred; p->p_tracecred = NULL; mtx_unlock(&ktrace_mtx); PROC_UNLOCK(p); if (tracevp != NULL) { locked = VFS_LOCK_GIANT(tracevp->v_mount); vrele(tracevp); VFS_UNLOCK_GIANT(locked); } if (tracecred != NULL) crfree(tracecred); #endif /* * Release reference to text vnode */ if ((vtmp = p->p_textvp) != NULL) { p->p_textvp = NULL; locked = VFS_LOCK_GIANT(vtmp->v_mount); vrele(vtmp); VFS_UNLOCK_GIANT(locked); } /* * Release our limits structure. */ PROC_LOCK(p); plim = p->p_limit; p->p_limit = NULL; PROC_UNLOCK(p); lim_free(plim); /* * Remove proc from allproc queue and pidhash chain. * Place onto zombproc. Unlink from parent's child list. */ sx_xlock(&allproc_lock); LIST_REMOVE(p, p_list); LIST_INSERT_HEAD(&zombproc, p, p_list); LIST_REMOVE(p, p_hash); sx_xunlock(&allproc_lock); /* * Reparent all of our children to init. */ sx_xlock(&proctree_lock); q = LIST_FIRST(&p->p_children); if (q != NULL) /* only need this if any child is S_ZOMB */ wakeup(initproc); for (; q != NULL; q = nq) { nq = LIST_NEXT(q, p_sibling); PROC_LOCK(q); proc_reparent(q, initproc); q->p_sigparent = SIGCHLD; /* * Traced processes are killed * since their existence means someone is screwing up. */ if (q->p_flag & P_TRACED) { q->p_flag &= ~(P_TRACED | P_STOPPED_TRACE); psignal(q, SIGKILL); } PROC_UNLOCK(q); } /* * Save exit status and finalize rusage info except for times, * adding in child rusage info later when our time is locked. */ PROC_LOCK(p); p->p_xstat = rv; p->p_xthread = td; p->p_stats->p_ru.ru_nvcsw++; *p->p_ru = p->p_stats->p_ru; /* * Notify interested parties of our demise. */ KNOTE_LOCKED(&p->p_klist, NOTE_EXIT); /* * Just delete all entries in the p_klist. At this point we won't * report any more events, and there are nasty race conditions that * can beat us if we don't. */ knlist_clear(&p->p_klist, 1); /* * Notify parent that we're gone. If parent has the PS_NOCLDWAIT * flag set, or if the handler is set to SIG_IGN, notify process * 1 instead (and hope it will handle this situation). */ PROC_LOCK(p->p_pptr); mtx_lock(&p->p_pptr->p_sigacts->ps_mtx); if (p->p_pptr->p_sigacts->ps_flag & (PS_NOCLDWAIT | PS_CLDSIGIGN)) { struct proc *pp; mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx); pp = p->p_pptr; PROC_UNLOCK(pp); proc_reparent(p, initproc); p->p_sigparent = SIGCHLD; PROC_LOCK(p->p_pptr); /* * If this was the last child of our parent, notify * parent, so in case he was wait(2)ing, he will * continue. */ if (LIST_EMPTY(&pp->p_children)) wakeup(pp); } else mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx); if (p->p_pptr == initproc) psignal(p->p_pptr, SIGCHLD); else if (p->p_sigparent != 0) { if (p->p_sigparent == SIGCHLD) childproc_exited(p); else /* LINUX thread */ psignal(p->p_pptr, p->p_sigparent); } PROC_UNLOCK(p->p_pptr); PROC_UNLOCK(p); /* * Finally, call machine-dependent code to release the remaining * resources including address space. * The address space is released by "vmspace_exitfree(p)" in * vm_waitproc(). */ cpu_exit(td); WITNESS_WARN(WARN_PANIC, &proctree_lock.sx_object, "process (pid %d) exiting", p->p_pid); PROC_LOCK(p); PROC_LOCK(p->p_pptr); sx_xunlock(&proctree_lock); /* * The state PRS_ZOMBIE prevents other proesses from sending * signal to the process, to avoid memory leak, we free memory * for signal queue at the time when the state is set. */ sigqueue_flush(&p->p_sigqueue); sigqueue_flush(&td->td_sigqueue); /* * We have to wait until after acquiring all locks before * changing p_state. We need to avoid all possible context * switches (including ones from blocking on a mutex) while * marked as a zombie. We also have to set the zombie state * before we release the parent process' proc lock to avoid * a lost wakeup. So, we first call wakeup, then we grab the * sched lock, update the state, and release the parent process' * proc lock. */ wakeup(p->p_pptr); mtx_lock_spin(&sched_lock); p->p_state = PRS_ZOMBIE; PROC_UNLOCK(p->p_pptr); sched_exit(p->p_pptr, td); /* * Hopefully no one will try to deliver a signal to the process this * late in the game. */ knlist_destroy(&p->p_klist); /* * Make sure the scheduler takes this thread out of its tables etc. * This will also release this thread's reference to the ucred. * Other thread parts to release include pcb bits and such. */ thread_exit(); } #ifndef _SYS_SYSPROTO_H_ struct abort2_args { char *why; int nargs; void **args; }; #endif /* * MPSAFE. */ int abort2(struct thread *td, struct abort2_args *uap) { struct proc *p = td->td_proc; struct sbuf *sb; void *uargs[16]; int error, i, sig; error = 0; /* satisfy compiler */ /* * Do it right now so we can log either proper call of abort2(), or * note, that invalid argument was passed. 512 is big enough to * handle 16 arguments' descriptions with additional comments. */ sb = sbuf_new(NULL, NULL, 512, SBUF_FIXEDLEN); sbuf_clear(sb); sbuf_printf(sb, "%s(pid %d uid %d) aborted: ", p->p_comm, p->p_pid, td->td_ucred->cr_uid); /* * Since we can't return from abort2(), send SIGKILL in cases, where * abort2() was called improperly */ sig = SIGKILL; /* Prevent from DoSes from user-space. */ if (uap->nargs < 0 || uap->nargs > 16) goto out; if (uap->args == NULL) goto out; error = copyin(uap->args, uargs, uap->nargs * sizeof(void *)); if (error != 0) goto out; /* * Limit size of 'reason' string to 128. Will fit even when * maximal number of arguments was chosen to be logged. */ if (uap->why != NULL) { error = sbuf_copyin(sb, uap->why, 128); if (error < 0) goto out; } else { sbuf_printf(sb, "(null)"); } if (uap->nargs) { sbuf_printf(sb, "("); for (i = 0;i < uap->nargs; i++) sbuf_printf(sb, "%s%p", i == 0 ? "" : ", ", uargs[i]); sbuf_printf(sb, ")"); } /* * Final stage: arguments were proper, string has been * successfully copied from userspace, and copying pointers * from user-space succeed. */ sig = SIGABRT; out: if (sig == SIGKILL) { sbuf_trim(sb); sbuf_printf(sb, " (Reason text inaccessible)"); } sbuf_cat(sb, "\n"); sbuf_finish(sb); log(LOG_INFO, "%s", sbuf_data(sb)); sbuf_delete(sb); exit1(td, W_EXITCODE(0, sig)); return (0); } #ifdef COMPAT_43 /* * The dirty work is handled by kern_wait(). * * MPSAFE. */ int owait(struct thread *td, struct owait_args *uap __unused) { int error, status; error = kern_wait(td, WAIT_ANY, &status, 0, NULL); if (error == 0) td->td_retval[1] = status; return (error); } #endif /* COMPAT_43 */ /* * The dirty work is handled by kern_wait(). * * MPSAFE. */ int wait4(struct thread *td, struct wait_args *uap) { struct rusage ru, *rup; int error, status; if (uap->rusage != NULL) rup = &ru; else rup = NULL; error = kern_wait(td, uap->pid, &status, uap->options, rup); if (uap->status != NULL && error == 0) error = copyout(&status, uap->status, sizeof(status)); if (uap->rusage != NULL && error == 0) error = copyout(&ru, uap->rusage, sizeof(struct rusage)); return (error); } int kern_wait(struct thread *td, pid_t pid, int *status, int options, struct rusage *rusage) { struct proc *p, *q, *t; int error, nfound; AUDIT_ARG(pid, pid); q = td->td_proc; if (pid == 0) { PROC_LOCK(q); pid = -q->p_pgid; PROC_UNLOCK(q); } if (options &~ (WUNTRACED|WNOHANG|WCONTINUED|WLINUXCLONE)) return (EINVAL); loop: if (q->p_flag & P_STATCHILD) { PROC_LOCK(q); q->p_flag &= ~P_STATCHILD; PROC_UNLOCK(q); } nfound = 0; sx_xlock(&proctree_lock); LIST_FOREACH(p, &q->p_children, p_sibling) { PROC_LOCK(p); if (pid != WAIT_ANY && p->p_pid != pid && p->p_pgid != -pid) { PROC_UNLOCK(p); continue; } if (p_canwait(td, p)) { PROC_UNLOCK(p); continue; } /* * This special case handles a kthread spawned by linux_clone * (see linux_misc.c). The linux_wait4 and linux_waitpid * functions need to be able to distinguish between waiting * on a process and waiting on a thread. It is a thread if * p_sigparent is not SIGCHLD, and the WLINUXCLONE option * signifies we want to wait for threads and not processes. */ if ((p->p_sigparent != SIGCHLD) ^ ((options & WLINUXCLONE) != 0)) { PROC_UNLOCK(p); continue; } nfound++; if (p->p_state == PRS_ZOMBIE) { /* * It is possible that the last thread of this * process is still running on another CPU * in thread_exit() after having dropped the process * lock via PROC_UNLOCK() but before it has completed * cpu_throw(). In that case, the other thread must * still hold sched_lock, so simply by acquiring * sched_lock once we will wait long enough for the * thread to exit in that case. */ mtx_lock_spin(&sched_lock); mtx_unlock_spin(&sched_lock); td->td_retval[0] = p->p_pid; if (status) *status = p->p_xstat; /* convert to int */ if (rusage) { *rusage = *p->p_ru; calcru(p, &rusage->ru_utime, &rusage->ru_stime); } PROC_LOCK(q); sigqueue_take(p->p_ksi); PROC_UNLOCK(q); /* * If we got the child via a ptrace 'attach', * we need to give it back to the old parent. */ PROC_UNLOCK(p); if (p->p_oppid && (t = pfind(p->p_oppid)) != NULL) { PROC_LOCK(p); p->p_oppid = 0; proc_reparent(p, t); PROC_UNLOCK(p); tdsignal(t, NULL, SIGCHLD, p->p_ksi); wakeup(t); PROC_UNLOCK(t); sx_xunlock(&proctree_lock); return (0); } /* * Remove other references to this process to ensure * we have an exclusive reference. */ sx_xlock(&allproc_lock); LIST_REMOVE(p, p_list); /* off zombproc */ sx_xunlock(&allproc_lock); LIST_REMOVE(p, p_sibling); leavepgrp(p); sx_xunlock(&proctree_lock); /* * As a side effect of this lock, we know that * all other writes to this proc are visible now, so * no more locking is needed for p. */ PROC_LOCK(p); p->p_xstat = 0; /* XXX: why? */ PROC_UNLOCK(p); PROC_LOCK(q); ruadd(&q->p_stats->p_cru, &q->p_crux, p->p_ru, &p->p_rux); PROC_UNLOCK(q); FREE(p->p_ru, M_ZOMBIE); p->p_ru = NULL; /* * Decrement the count of procs running with this uid. */ (void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0); /* * Free credentials, arguments, and sigacts. */ crfree(p->p_ucred); p->p_ucred = NULL; pargs_drop(p->p_args); p->p_args = NULL; sigacts_free(p->p_sigacts); p->p_sigacts = NULL; /* * Do any thread-system specific cleanups. */ thread_wait(p); /* * Give vm and machine-dependent layer a chance * to free anything that cpu_exit couldn't * release while still running in process context. */ vm_waitproc(p); #ifdef MAC mac_destroy_proc(p); #endif #ifdef AUDIT audit_proc_free(p); #endif KASSERT(FIRST_THREAD_IN_PROC(p), ("kern_wait: no residual thread!")); uma_zfree(proc_zone, p); sx_xlock(&allproc_lock); nprocs--; sx_xunlock(&allproc_lock); return (0); } mtx_lock_spin(&sched_lock); if ((p->p_flag & P_STOPPED_SIG) && (p->p_suspcount == p->p_numthreads) && (p->p_flag & P_WAITED) == 0 && (p->p_flag & P_TRACED || options & WUNTRACED)) { mtx_unlock_spin(&sched_lock); p->p_flag |= P_WAITED; sx_xunlock(&proctree_lock); td->td_retval[0] = p->p_pid; if (status) *status = W_STOPCODE(p->p_xstat); PROC_LOCK(q); sigqueue_take(p->p_ksi); PROC_UNLOCK(q); PROC_UNLOCK(p); return (0); } mtx_unlock_spin(&sched_lock); if (options & WCONTINUED && (p->p_flag & P_CONTINUED)) { sx_xunlock(&proctree_lock); td->td_retval[0] = p->p_pid; p->p_flag &= ~P_CONTINUED; PROC_LOCK(q); sigqueue_take(p->p_ksi); PROC_UNLOCK(q); PROC_UNLOCK(p); if (status) *status = SIGCONT; return (0); } PROC_UNLOCK(p); } if (nfound == 0) { sx_xunlock(&proctree_lock); return (ECHILD); } if (options & WNOHANG) { sx_xunlock(&proctree_lock); td->td_retval[0] = 0; return (0); } PROC_LOCK(q); sx_xunlock(&proctree_lock); if (q->p_flag & P_STATCHILD) { q->p_flag &= ~P_STATCHILD; error = 0; } else error = msleep(q, &q->p_mtx, PWAIT | PCATCH, "wait", 0); PROC_UNLOCK(q); if (error) return (error); goto loop; } /* * Make process 'parent' the new parent of process 'child'. * Must be called with an exclusive hold of proctree lock. */ void proc_reparent(struct proc *child, struct proc *parent) { sx_assert(&proctree_lock, SX_XLOCKED); PROC_LOCK_ASSERT(child, MA_OWNED); if (child->p_pptr == parent) return; + PROC_LOCK(child->p_pptr); + sigqueue_take(child->p_ksi); + PROC_UNLOCK(child->p_pptr); LIST_REMOVE(child, p_sibling); LIST_INSERT_HEAD(&parent->p_children, child, p_sibling); child->p_pptr = parent; } Index: head/sys/kern/sys_process.c =================================================================== --- head/sys/kern/sys_process.c (revision 163675) +++ head/sys/kern/sys_process.c (revision 163676) @@ -1,1030 +1,1026 @@ /*- * Copyright (c) 1994, Sean Eric Fagan * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Sean Eric Fagan. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include "opt_compat.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef COMPAT_IA32 #include #include #include extern struct sysentvec ia32_freebsd_sysvec; struct ptrace_io_desc32 { int piod_op; u_int32_t piod_offs; u_int32_t piod_addr; u_int32_t piod_len; }; #endif /* * Functions implemented using PROC_ACTION(): * * proc_read_regs(proc, regs) * Get the current user-visible register set from the process * and copy it into the regs structure (). * The process is stopped at the time read_regs is called. * * proc_write_regs(proc, regs) * Update the current register set from the passed in regs * structure. Take care to avoid clobbering special CPU * registers or privileged bits in the PSL. * Depending on the architecture this may have fix-up work to do, * especially if the IAR or PCW are modified. * The process is stopped at the time write_regs is called. * * proc_read_fpregs, proc_write_fpregs * deal with the floating point register set, otherwise as above. * * proc_read_dbregs, proc_write_dbregs * deal with the processor debug register set, otherwise as above. * * proc_sstep(proc) * Arrange for the process to trap after executing a single instruction. */ #define PROC_ACTION(action) do { \ int error; \ \ PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \ if ((td->td_proc->p_sflag & PS_INMEM) == 0) \ error = EIO; \ else \ error = (action); \ return (error); \ } while(0) int proc_read_regs(struct thread *td, struct reg *regs) { PROC_ACTION(fill_regs(td, regs)); } int proc_write_regs(struct thread *td, struct reg *regs) { PROC_ACTION(set_regs(td, regs)); } int proc_read_dbregs(struct thread *td, struct dbreg *dbregs) { PROC_ACTION(fill_dbregs(td, dbregs)); } int proc_write_dbregs(struct thread *td, struct dbreg *dbregs) { PROC_ACTION(set_dbregs(td, dbregs)); } /* * Ptrace doesn't support fpregs at all, and there are no security holes * or translations for fpregs, so we can just copy them. */ int proc_read_fpregs(struct thread *td, struct fpreg *fpregs) { PROC_ACTION(fill_fpregs(td, fpregs)); } int proc_write_fpregs(struct thread *td, struct fpreg *fpregs) { PROC_ACTION(set_fpregs(td, fpregs)); } #ifdef COMPAT_IA32 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */ int proc_read_regs32(struct thread *td, struct reg32 *regs32) { PROC_ACTION(fill_regs32(td, regs32)); } int proc_write_regs32(struct thread *td, struct reg32 *regs32) { PROC_ACTION(set_regs32(td, regs32)); } int proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32) { PROC_ACTION(fill_dbregs32(td, dbregs32)); } int proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32) { PROC_ACTION(set_dbregs32(td, dbregs32)); } int proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32) { PROC_ACTION(fill_fpregs32(td, fpregs32)); } int proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32) { PROC_ACTION(set_fpregs32(td, fpregs32)); } #endif int proc_sstep(struct thread *td) { PROC_ACTION(ptrace_single_step(td)); } int proc_rwmem(struct proc *p, struct uio *uio) { vm_map_t map; vm_object_t backing_object, object = NULL; vm_offset_t pageno = 0; /* page number */ vm_prot_t reqprot; int error, writing; /* * Assert that someone has locked this vmspace. (Should be * curthread but we can't assert that.) This keeps the process * from exiting out from under us until this operation completes. */ KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__, p, p->p_pid)); /* * The map we want... */ map = &p->p_vmspace->vm_map; writing = uio->uio_rw == UIO_WRITE; reqprot = writing ? (VM_PROT_WRITE | VM_PROT_OVERRIDE_WRITE) : VM_PROT_READ; /* * Only map in one page at a time. We don't have to, but it * makes things easier. This way is trivial - right? */ do { vm_map_t tmap; vm_offset_t uva; int page_offset; /* offset into page */ vm_map_entry_t out_entry; vm_prot_t out_prot; boolean_t wired; vm_pindex_t pindex; u_int len; vm_page_t m; object = NULL; uva = (vm_offset_t)uio->uio_offset; /* * Get the page number of this segment. */ pageno = trunc_page(uva); page_offset = uva - pageno; /* * How many bytes to copy */ len = min(PAGE_SIZE - page_offset, uio->uio_resid); /* * Fault the page on behalf of the process */ error = vm_fault(map, pageno, reqprot, VM_FAULT_NORMAL); if (error) { error = EFAULT; break; } /* * Now we need to get the page. out_entry, out_prot, wired, * and single_use aren't used. One would think the vm code * would be a *bit* nicer... We use tmap because * vm_map_lookup() can change the map argument. */ tmap = map; error = vm_map_lookup(&tmap, pageno, reqprot, &out_entry, &object, &pindex, &out_prot, &wired); if (error) { error = EFAULT; break; } VM_OBJECT_LOCK(object); while ((m = vm_page_lookup(object, pindex)) == NULL && !writing && (backing_object = object->backing_object) != NULL) { /* * Allow fallback to backing objects if we are reading. */ VM_OBJECT_LOCK(backing_object); pindex += OFF_TO_IDX(object->backing_object_offset); VM_OBJECT_UNLOCK(object); object = backing_object; } VM_OBJECT_UNLOCK(object); if (m == NULL) { vm_map_lookup_done(tmap, out_entry); error = EFAULT; break; } /* * Hold the page in memory. */ vm_page_lock_queues(); vm_page_hold(m); vm_page_unlock_queues(); /* * We're done with tmap now. */ vm_map_lookup_done(tmap, out_entry); /* * Now do the i/o move. */ error = uiomove_fromphys(&m, page_offset, len, uio); /* * Release the page. */ vm_page_lock_queues(); vm_page_unhold(m); vm_page_unlock_queues(); } while (error == 0 && uio->uio_resid > 0); return (error); } /* * Process debugging system call. */ #ifndef _SYS_SYSPROTO_H_ struct ptrace_args { int req; pid_t pid; caddr_t addr; int data; }; #endif #ifdef COMPAT_IA32 /* * This CPP subterfuge is to try and reduce the number of ifdefs in * the body of the code. * COPYIN(uap->addr, &r.reg, sizeof r.reg); * becomes either: * copyin(uap->addr, &r.reg, sizeof r.reg); * or * copyin(uap->addr, &r.reg32, sizeof r.reg32); * .. except this is done at runtime. */ #define COPYIN(u, k, s) wrap32 ? \ copyin(u, k ## 32, s ## 32) : \ copyin(u, k, s) #define COPYOUT(k, u, s) wrap32 ? \ copyout(k ## 32, u, s ## 32) : \ copyout(k, u, s) #else #define COPYIN(u, k, s) copyin(u, k, s) #define COPYOUT(k, u, s) copyout(k, u, s) #endif /* * MPSAFE */ int ptrace(struct thread *td, struct ptrace_args *uap) { /* * XXX this obfuscation is to reduce stack usage, but the register * structs may be too large to put on the stack anyway. */ union { struct ptrace_io_desc piod; struct ptrace_lwpinfo pl; struct dbreg dbreg; struct fpreg fpreg; struct reg reg; #ifdef COMPAT_IA32 struct dbreg32 dbreg32; struct fpreg32 fpreg32; struct reg32 reg32; struct ptrace_io_desc32 piod32; #endif } r; void *addr; int error = 0; #ifdef COMPAT_IA32 int wrap32 = 0; if (td->td_proc->p_sysent == &ia32_freebsd_sysvec) wrap32 = 1; #endif AUDIT_ARG(pid, uap->pid); AUDIT_ARG(cmd, uap->req); AUDIT_ARG(addr, uap->addr); AUDIT_ARG(value, uap->data); addr = &r; switch (uap->req) { case PT_GETREGS: case PT_GETFPREGS: case PT_GETDBREGS: case PT_LWPINFO: break; case PT_SETREGS: error = COPYIN(uap->addr, &r.reg, sizeof r.reg); break; case PT_SETFPREGS: error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg); break; case PT_SETDBREGS: error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg); break; case PT_IO: error = COPYIN(uap->addr, &r.piod, sizeof r.piod); break; default: addr = uap->addr; break; } if (error) return (error); error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data); if (error) return (error); switch (uap->req) { case PT_IO: error = COPYOUT(&r.piod, uap->addr, sizeof r.piod); break; case PT_GETREGS: error = COPYOUT(&r.reg, uap->addr, sizeof r.reg); break; case PT_GETFPREGS: error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg); break; case PT_GETDBREGS: error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg); break; case PT_LWPINFO: error = copyout(&r.pl, uap->addr, uap->data); break; } return (error); } #undef COPYIN #undef COPYOUT #ifdef COMPAT_IA32 /* * PROC_READ(regs, td2, addr); * becomes either: * proc_read_regs(td2, addr); * or * proc_read_regs32(td2, addr); * .. except this is done at runtime. There is an additional * complication in that PROC_WRITE disallows 32 bit consumers * from writing to 64 bit address space targets. */ #define PROC_READ(w, t, a) wrap32 ? \ proc_read_ ## w ## 32(t, a) : \ proc_read_ ## w (t, a) #define PROC_WRITE(w, t, a) wrap32 ? \ (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \ proc_write_ ## w (t, a) #else #define PROC_READ(w, t, a) proc_read_ ## w (t, a) #define PROC_WRITE(w, t, a) proc_write_ ## w (t, a) #endif int kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) { struct iovec iov; struct uio uio; struct proc *curp, *p, *pp; struct thread *td2 = NULL; struct ptrace_io_desc *piod = NULL; struct ptrace_lwpinfo *pl; int error, write, tmp, num; int proctree_locked = 0; lwpid_t tid = 0, *buf; #ifdef COMPAT_IA32 int wrap32 = 0, safe = 0; struct ptrace_io_desc32 *piod32 = NULL; #endif curp = td->td_proc; /* Lock proctree before locking the process. */ switch (req) { case PT_TRACE_ME: case PT_ATTACH: case PT_STEP: case PT_CONTINUE: case PT_TO_SCE: case PT_TO_SCX: case PT_SYSCALL: case PT_DETACH: sx_xlock(&proctree_lock); proctree_locked = 1; break; default: break; } write = 0; if (req == PT_TRACE_ME) { p = td->td_proc; PROC_LOCK(p); } else { if (pid <= PID_MAX) { if ((p = pfind(pid)) == NULL) { if (proctree_locked) sx_xunlock(&proctree_lock); return (ESRCH); } } else { /* this is slow, should be optimized */ sx_slock(&allproc_lock); FOREACH_PROC_IN_SYSTEM(p) { PROC_LOCK(p); mtx_lock_spin(&sched_lock); FOREACH_THREAD_IN_PROC(p, td2) { if (td2->td_tid == pid) break; } mtx_unlock_spin(&sched_lock); if (td2 != NULL) break; /* proc lock held */ PROC_UNLOCK(p); } sx_sunlock(&allproc_lock); if (p == NULL) { if (proctree_locked) sx_xunlock(&proctree_lock); return (ESRCH); } tid = pid; pid = p->p_pid; } } AUDIT_ARG(process, p); if ((p->p_flag & P_WEXIT) != 0) { error = ESRCH; goto fail; } if ((error = p_cansee(td, p)) != 0) goto fail; if ((error = p_candebug(td, p)) != 0) goto fail; /* * System processes can't be debugged. */ if ((p->p_flag & P_SYSTEM) != 0) { error = EINVAL; goto fail; } if (tid == 0) { if ((p->p_flag & P_STOPPED_TRACE) != 0) { KASSERT(p->p_xthread != NULL, ("NULL p_xthread")); td2 = p->p_xthread; } else { td2 = FIRST_THREAD_IN_PROC(p); } tid = td2->td_tid; } #ifdef COMPAT_IA32 /* * Test if we're a 32 bit client and what the target is. * Set the wrap controls accordingly. */ if (td->td_proc->p_sysent == &ia32_freebsd_sysvec) { if (td2->td_proc->p_sysent == &ia32_freebsd_sysvec) safe = 1; wrap32 = 1; } #endif /* * Permissions check */ switch (req) { case PT_TRACE_ME: /* Always legal. */ break; case PT_ATTACH: /* Self */ if (p->p_pid == td->td_proc->p_pid) { error = EINVAL; goto fail; } /* Already traced */ if (p->p_flag & P_TRACED) { error = EBUSY; goto fail; } /* Can't trace an ancestor if you're being traced. */ if (curp->p_flag & P_TRACED) { for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) { if (pp == p) { error = EINVAL; goto fail; } } } /* OK */ break; case PT_CLEARSTEP: /* Allow thread to clear single step for itself */ if (td->td_tid == tid) break; /* FALLTHROUGH */ default: /* not being traced... */ if ((p->p_flag & P_TRACED) == 0) { error = EPERM; goto fail; } /* not being traced by YOU */ if (p->p_pptr != td->td_proc) { error = EBUSY; goto fail; } /* not currently stopped */ if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 || p->p_suspcount != p->p_numthreads || (p->p_flag & P_WAITED) == 0) { error = EBUSY; goto fail; } if ((p->p_flag & P_STOPPED_TRACE) == 0) { static int count = 0; if (count++ == 0) printf("P_STOPPED_TRACE not set.\n"); } /* OK */ break; } /* Keep this process around until we finish this request. */ _PHOLD(p); #ifdef FIX_SSTEP /* * Single step fixup ala procfs */ FIX_SSTEP(td2); #endif /* * Actually do the requests */ td->td_retval[0] = 0; switch (req) { case PT_TRACE_ME: /* set my trace flag and "owner" so it can read/write me */ p->p_flag |= P_TRACED; p->p_oppid = p->p_pptr->p_pid; break; case PT_ATTACH: /* security check done above */ p->p_flag |= P_TRACED; p->p_oppid = p->p_pptr->p_pid; - if (p->p_pptr != td->td_proc) { - PROC_LOCK(p->p_pptr); - sigqueue_take(p->p_ksi); - PROC_UNLOCK(p->p_pptr); + if (p->p_pptr != td->td_proc) proc_reparent(p, td->td_proc); - } data = SIGSTOP; goto sendsig; /* in PT_CONTINUE below */ case PT_CLEARSTEP: error = ptrace_clear_single_step(td2); break; case PT_SETSTEP: error = ptrace_single_step(td2); break; case PT_SUSPEND: mtx_lock_spin(&sched_lock); td2->td_flags |= TDF_DBSUSPEND; mtx_unlock_spin(&sched_lock); break; case PT_RESUME: mtx_lock_spin(&sched_lock); td2->td_flags &= ~TDF_DBSUSPEND; mtx_unlock_spin(&sched_lock); break; case PT_STEP: case PT_CONTINUE: case PT_TO_SCE: case PT_TO_SCX: case PT_SYSCALL: case PT_DETACH: /* Zero means do not send any signal */ if (data < 0 || data > _SIG_MAXSIG) { error = EINVAL; break; } switch (req) { case PT_STEP: error = ptrace_single_step(td2); if (error) goto out; break; case PT_TO_SCE: p->p_stops |= S_PT_SCE; break; case PT_TO_SCX: p->p_stops |= S_PT_SCX; break; case PT_SYSCALL: p->p_stops |= S_PT_SCE | S_PT_SCX; break; } if (addr != (void *)1) { error = ptrace_set_pc(td2, (u_long)(uintfptr_t)addr); if (error) break; } if (req == PT_DETACH) { /* reset process parent */ if (p->p_oppid != p->p_pptr->p_pid) { struct proc *pp; PROC_LOCK(p->p_pptr); sigqueue_take(p->p_ksi); PROC_UNLOCK(p->p_pptr); PROC_UNLOCK(p); pp = pfind(p->p_oppid); if (pp == NULL) pp = initproc; else PROC_UNLOCK(pp); PROC_LOCK(p); proc_reparent(p, pp); if (pp == initproc) p->p_sigparent = SIGCHLD; } p->p_flag &= ~(P_TRACED | P_WAITED); p->p_oppid = 0; /* should we send SIGCHLD? */ /* childproc_continued(p); */ } sendsig: if (proctree_locked) { sx_xunlock(&proctree_lock); proctree_locked = 0; } /* deliver or queue signal */ mtx_lock_spin(&sched_lock); td2->td_flags &= ~TDF_XSIG; mtx_unlock_spin(&sched_lock); td2->td_xsig = data; p->p_xstat = data; p->p_xthread = NULL; if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) { mtx_lock_spin(&sched_lock); if (req == PT_DETACH) { struct thread *td3; FOREACH_THREAD_IN_PROC(p, td3) td3->td_flags &= ~TDF_DBSUSPEND; } /* * unsuspend all threads, to not let a thread run, * you should use PT_SUSPEND to suspend it before * continuing process. */ mtx_unlock_spin(&sched_lock); thread_continued(p); p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED); mtx_lock_spin(&sched_lock); thread_unsuspend(p); mtx_unlock_spin(&sched_lock); } if (data) psignal(p, data); break; case PT_WRITE_I: case PT_WRITE_D: write = 1; /* FALLTHROUGH */ case PT_READ_I: case PT_READ_D: PROC_UNLOCK(p); tmp = 0; /* write = 0 set above */ iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp; iov.iov_len = sizeof(int); uio.uio_iov = &iov; uio.uio_iovcnt = 1; uio.uio_offset = (off_t)(uintptr_t)addr; uio.uio_resid = sizeof(int); uio.uio_segflg = UIO_SYSSPACE; /* i.e.: the uap */ uio.uio_rw = write ? UIO_WRITE : UIO_READ; uio.uio_td = td; error = proc_rwmem(p, &uio); if (uio.uio_resid != 0) { /* * XXX proc_rwmem() doesn't currently return ENOSPC, * so I think write() can bogusly return 0. * XXX what happens for short writes? We don't want * to write partial data. * XXX proc_rwmem() returns EPERM for other invalid * addresses. Convert this to EINVAL. Does this * clobber returns of EPERM for other reasons? */ if (error == 0 || error == ENOSPC || error == EPERM) error = EINVAL; /* EOF */ } if (!write) td->td_retval[0] = tmp; PROC_LOCK(p); break; case PT_IO: #ifdef COMPAT_IA32 if (wrap32) { piod32 = addr; iov.iov_base = (void *)(uintptr_t)piod32->piod_addr; iov.iov_len = piod32->piod_len; uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs; uio.uio_resid = piod32->piod_len; } else #endif { piod = addr; iov.iov_base = piod->piod_addr; iov.iov_len = piod->piod_len; uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; uio.uio_resid = piod->piod_len; } uio.uio_iov = &iov; uio.uio_iovcnt = 1; uio.uio_segflg = UIO_USERSPACE; uio.uio_td = td; #ifdef COMPAT_IA32 tmp = wrap32 ? piod32->piod_op : piod->piod_op; #else tmp = piod->piod_op; #endif switch (tmp) { case PIOD_READ_D: case PIOD_READ_I: uio.uio_rw = UIO_READ; break; case PIOD_WRITE_D: case PIOD_WRITE_I: uio.uio_rw = UIO_WRITE; break; default: error = EINVAL; goto out; } PROC_UNLOCK(p); error = proc_rwmem(p, &uio); #ifdef COMPAT_IA32 if (wrap32) piod32->piod_len -= uio.uio_resid; else #endif piod->piod_len -= uio.uio_resid; PROC_LOCK(p); break; case PT_KILL: data = SIGKILL; goto sendsig; /* in PT_CONTINUE above */ case PT_SETREGS: error = PROC_WRITE(regs, td2, addr); break; case PT_GETREGS: error = PROC_READ(regs, td2, addr); break; case PT_SETFPREGS: error = PROC_WRITE(fpregs, td2, addr); break; case PT_GETFPREGS: error = PROC_READ(fpregs, td2, addr); break; case PT_SETDBREGS: error = PROC_WRITE(dbregs, td2, addr); break; case PT_GETDBREGS: error = PROC_READ(dbregs, td2, addr); break; case PT_LWPINFO: if (data <= 0 || data > sizeof(*pl)) { error = EINVAL; break; } pl = addr; pl->pl_lwpid = td2->td_tid; if (td2->td_flags & TDF_XSIG) pl->pl_event = PL_EVENT_SIGNAL; else pl->pl_event = 0; if (td2->td_pflags & TDP_SA) { pl->pl_flags = PL_FLAG_SA; if (td2->td_upcall && !TD_CAN_UNBIND(td2)) pl->pl_flags |= PL_FLAG_BOUND; } else { pl->pl_flags = 0; } pl->pl_sigmask = td2->td_sigmask; pl->pl_siglist = td2->td_siglist; break; case PT_GETNUMLWPS: td->td_retval[0] = p->p_numthreads; break; case PT_GETLWPLIST: if (data <= 0) { error = EINVAL; break; } num = imin(p->p_numthreads, data); PROC_UNLOCK(p); buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK); tmp = 0; PROC_LOCK(p); mtx_lock_spin(&sched_lock); FOREACH_THREAD_IN_PROC(p, td2) { if (tmp >= num) break; buf[tmp++] = td2->td_tid; } mtx_unlock_spin(&sched_lock); PROC_UNLOCK(p); error = copyout(buf, addr, tmp * sizeof(lwpid_t)); free(buf, M_TEMP); if (!error) td->td_retval[0] = tmp; PROC_LOCK(p); break; default: #ifdef __HAVE_PTRACE_MACHDEP if (req >= PT_FIRSTMACH) { PROC_UNLOCK(p); error = cpu_ptrace(td2, req, addr, data); PROC_LOCK(p); } else #endif /* Unknown request. */ error = EINVAL; break; } out: /* Drop our hold on this process now that the request has completed. */ _PRELE(p); fail: PROC_UNLOCK(p); if (proctree_locked) sx_xunlock(&proctree_lock); return (error); } #undef PROC_READ #undef PROC_WRITE /* * Stop a process because of a debugging event; * stay stopped until p->p_step is cleared * (cleared by PIOCCONT in procfs). */ void stopevent(struct proc *p, unsigned int event, unsigned int val) { PROC_LOCK_ASSERT(p, MA_OWNED); p->p_step = 1; do { p->p_xstat = val; p->p_xthread = NULL; p->p_stype = event; /* Which event caused the stop? */ wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */ msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0); } while (p->p_step); }