Index: stable/10/sys/kern/kern_exec.c =================================================================== --- stable/10/sys/kern/kern_exec.c (revision 270083) +++ stable/10/sys/kern/kern_exec.c (revision 270084) @@ -1,1522 +1,1521 @@ /*- * Copyright (c) 1993, David Greenman * 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. * * 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_capsicum.h" #include "opt_hwpmc_hooks.h" #include "opt_kdtrace.h" #include "opt_ktrace.h" #include "opt_vm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef KTRACE #include #endif #include #include #include #include #include #include #include #include #include #ifdef HWPMC_HOOKS #include #endif #include #include #include #ifdef KDTRACE_HOOKS #include dtrace_execexit_func_t dtrace_fasttrap_exec; #endif SDT_PROVIDER_DECLARE(proc); SDT_PROBE_DEFINE1(proc, kernel, , exec, "char *"); SDT_PROBE_DEFINE1(proc, kernel, , exec__failure, "int"); SDT_PROBE_DEFINE1(proc, kernel, , exec__success, "char *"); MALLOC_DEFINE(M_PARGS, "proc-args", "Process arguments"); static int sysctl_kern_ps_strings(SYSCTL_HANDLER_ARGS); static int sysctl_kern_usrstack(SYSCTL_HANDLER_ARGS); static int sysctl_kern_stackprot(SYSCTL_HANDLER_ARGS); static int do_execve(struct thread *td, struct image_args *args, struct mac *mac_p); /* XXX This should be vm_size_t. */ SYSCTL_PROC(_kern, KERN_PS_STRINGS, ps_strings, CTLTYPE_ULONG|CTLFLAG_RD, NULL, 0, sysctl_kern_ps_strings, "LU", ""); /* XXX This should be vm_size_t. */ SYSCTL_PROC(_kern, KERN_USRSTACK, usrstack, CTLTYPE_ULONG|CTLFLAG_RD| CTLFLAG_CAPRD, NULL, 0, sysctl_kern_usrstack, "LU", ""); SYSCTL_PROC(_kern, OID_AUTO, stackprot, CTLTYPE_INT|CTLFLAG_RD, NULL, 0, sysctl_kern_stackprot, "I", ""); u_long ps_arg_cache_limit = PAGE_SIZE / 16; SYSCTL_ULONG(_kern, OID_AUTO, ps_arg_cache_limit, CTLFLAG_RW, &ps_arg_cache_limit, 0, ""); static int disallow_high_osrel; SYSCTL_INT(_kern, OID_AUTO, disallow_high_osrel, CTLFLAG_RW, &disallow_high_osrel, 0, "Disallow execution of binaries built for higher version of the world"); static int map_at_zero = 0; TUNABLE_INT("security.bsd.map_at_zero", &map_at_zero); SYSCTL_INT(_security_bsd, OID_AUTO, map_at_zero, CTLFLAG_RW, &map_at_zero, 0, "Permit processes to map an object at virtual address 0."); static int sysctl_kern_ps_strings(SYSCTL_HANDLER_ARGS) { struct proc *p; int error; p = curproc; #ifdef SCTL_MASK32 if (req->flags & SCTL_MASK32) { unsigned int val; val = (unsigned int)p->p_sysent->sv_psstrings; error = SYSCTL_OUT(req, &val, sizeof(val)); } else #endif error = SYSCTL_OUT(req, &p->p_sysent->sv_psstrings, sizeof(p->p_sysent->sv_psstrings)); return error; } static int sysctl_kern_usrstack(SYSCTL_HANDLER_ARGS) { struct proc *p; int error; p = curproc; #ifdef SCTL_MASK32 if (req->flags & SCTL_MASK32) { unsigned int val; val = (unsigned int)p->p_sysent->sv_usrstack; error = SYSCTL_OUT(req, &val, sizeof(val)); } else #endif error = SYSCTL_OUT(req, &p->p_sysent->sv_usrstack, sizeof(p->p_sysent->sv_usrstack)); return error; } static int sysctl_kern_stackprot(SYSCTL_HANDLER_ARGS) { struct proc *p; p = curproc; return (SYSCTL_OUT(req, &p->p_sysent->sv_stackprot, sizeof(p->p_sysent->sv_stackprot))); } /* * Each of the items is a pointer to a `const struct execsw', hence the * double pointer here. */ static const struct execsw **execsw; #ifndef _SYS_SYSPROTO_H_ struct execve_args { char *fname; char **argv; char **envv; }; #endif int sys_execve(td, uap) struct thread *td; struct execve_args /* { char *fname; char **argv; char **envv; } */ *uap; { int error; struct image_args args; error = exec_copyin_args(&args, uap->fname, UIO_USERSPACE, uap->argv, uap->envv); if (error == 0) error = kern_execve(td, &args, NULL); return (error); } #ifndef _SYS_SYSPROTO_H_ struct fexecve_args { int fd; char **argv; char **envv; } #endif int sys_fexecve(struct thread *td, struct fexecve_args *uap) { int error; struct image_args args; error = exec_copyin_args(&args, NULL, UIO_SYSSPACE, uap->argv, uap->envv); if (error == 0) { args.fd = uap->fd; error = kern_execve(td, &args, NULL); } return (error); } #ifndef _SYS_SYSPROTO_H_ struct __mac_execve_args { char *fname; char **argv; char **envv; struct mac *mac_p; }; #endif int sys___mac_execve(td, uap) struct thread *td; struct __mac_execve_args /* { char *fname; char **argv; char **envv; struct mac *mac_p; } */ *uap; { #ifdef MAC int error; struct image_args args; error = exec_copyin_args(&args, uap->fname, UIO_USERSPACE, uap->argv, uap->envv); if (error == 0) error = kern_execve(td, &args, uap->mac_p); return (error); #else return (ENOSYS); #endif } /* * XXX: kern_execve has the astonishing property of not always returning to * the caller. If sufficiently bad things happen during the call to * do_execve(), it can end up calling exit1(); as a result, callers must * avoid doing anything which they might need to undo (e.g., allocating * memory). */ int kern_execve(td, args, mac_p) struct thread *td; struct image_args *args; struct mac *mac_p; { struct proc *p = td->td_proc; struct vmspace *oldvmspace; int error; AUDIT_ARG_ARGV(args->begin_argv, args->argc, args->begin_envv - args->begin_argv); AUDIT_ARG_ENVV(args->begin_envv, args->envc, args->endp - args->begin_envv); if (p->p_flag & P_HADTHREADS) { PROC_LOCK(p); if (thread_single(SINGLE_BOUNDARY)) { PROC_UNLOCK(p); exec_free_args(args); return (ERESTART); /* Try again later. */ } PROC_UNLOCK(p); } KASSERT((td->td_pflags & TDP_EXECVMSPC) == 0, ("nested execve")); oldvmspace = td->td_proc->p_vmspace; error = do_execve(td, args, mac_p); if (p->p_flag & P_HADTHREADS) { PROC_LOCK(p); /* * If success, we upgrade to SINGLE_EXIT state to * force other threads to suicide. */ if (error == 0) thread_single(SINGLE_EXIT); else thread_single_end(); PROC_UNLOCK(p); } if ((td->td_pflags & TDP_EXECVMSPC) != 0) { KASSERT(td->td_proc->p_vmspace != oldvmspace, ("oldvmspace still used")); vmspace_free(oldvmspace); td->td_pflags &= ~TDP_EXECVMSPC; } return (error); } /* * In-kernel implementation of execve(). All arguments are assumed to be * userspace pointers from the passed thread. */ static int do_execve(td, args, mac_p) struct thread *td; struct image_args *args; struct mac *mac_p; { struct proc *p = td->td_proc; struct nameidata nd; struct ucred *newcred = NULL, *oldcred; struct uidinfo *euip; register_t *stack_base; int error, i; struct image_params image_params, *imgp; struct vattr attr; int (*img_first)(struct image_params *); struct pargs *oldargs = NULL, *newargs = NULL; struct sigacts *oldsigacts, *newsigacts; #ifdef KTRACE struct vnode *tracevp = NULL; struct ucred *tracecred = NULL; #endif struct vnode *textvp = NULL, *binvp = NULL; cap_rights_t rights; int credential_changing; int textset; #ifdef MAC struct label *interpvplabel = NULL; int will_transition; #endif #ifdef HWPMC_HOOKS struct pmckern_procexec pe; #endif static const char fexecv_proc_title[] = "(fexecv)"; imgp = &image_params; /* * Lock the process and set the P_INEXEC flag to indicate that * it should be left alone until we're done here. This is * necessary to avoid race conditions - e.g. in ptrace() - * that might allow a local user to illicitly obtain elevated * privileges. */ PROC_LOCK(p); KASSERT((p->p_flag & P_INEXEC) == 0, ("%s(): process already has P_INEXEC flag", __func__)); p->p_flag |= P_INEXEC; PROC_UNLOCK(p); /* * Initialize part of the common data */ imgp->proc = p; imgp->execlabel = NULL; imgp->attr = &attr; imgp->entry_addr = 0; imgp->reloc_base = 0; imgp->vmspace_destroyed = 0; imgp->interpreted = 0; imgp->opened = 0; imgp->interpreter_name = NULL; imgp->auxargs = NULL; imgp->vp = NULL; imgp->object = NULL; imgp->firstpage = NULL; imgp->ps_strings = 0; imgp->auxarg_size = 0; imgp->args = args; imgp->execpath = imgp->freepath = NULL; imgp->execpathp = 0; imgp->canary = 0; imgp->canarylen = 0; imgp->pagesizes = 0; imgp->pagesizeslen = 0; imgp->stack_prot = 0; #ifdef MAC error = mac_execve_enter(imgp, mac_p); if (error) goto exec_fail; #endif imgp->image_header = NULL; /* * Translate the file name. namei() returns a vnode pointer * in ni_vp amoung other things. * * XXXAUDIT: It would be desirable to also audit the name of the * interpreter if this is an interpreted binary. */ if (args->fname != NULL) { NDINIT(&nd, LOOKUP, ISOPEN | LOCKLEAF | FOLLOW | SAVENAME | AUDITVNODE1, UIO_SYSSPACE, args->fname, td); } SDT_PROBE(proc, kernel, , exec, args->fname, 0, 0, 0, 0 ); interpret: if (args->fname != NULL) { #ifdef CAPABILITY_MODE /* * While capability mode can't reach this point via direct * path arguments to execve(), we also don't allow * interpreters to be used in capability mode (for now). * Catch indirect lookups and return a permissions error. */ if (IN_CAPABILITY_MODE(td)) { error = ECAPMODE; goto exec_fail; } #endif error = namei(&nd); if (error) goto exec_fail; binvp = nd.ni_vp; imgp->vp = binvp; } else { AUDIT_ARG_FD(args->fd); /* * Descriptors opened only with O_EXEC or O_RDONLY are allowed. */ error = fgetvp_exec(td, args->fd, cap_rights_init(&rights, CAP_FEXECVE), &binvp); if (error) goto exec_fail; vn_lock(binvp, LK_EXCLUSIVE | LK_RETRY); AUDIT_ARG_VNODE1(binvp); imgp->vp = binvp; } /* * Check file permissions (also 'opens' file) */ error = exec_check_permissions(imgp); if (error) goto exec_fail_dealloc; imgp->object = imgp->vp->v_object; if (imgp->object != NULL) vm_object_reference(imgp->object); /* * Set VV_TEXT now so no one can write to the executable while we're * activating it. * * Remember if this was set before and unset it in case this is not * actually an executable image. */ textset = VOP_IS_TEXT(imgp->vp); VOP_SET_TEXT(imgp->vp); error = exec_map_first_page(imgp); if (error) goto exec_fail_dealloc; imgp->proc->p_osrel = 0; /* * If the current process has a special image activator it * wants to try first, call it. For example, emulating shell * scripts differently. */ error = -1; if ((img_first = imgp->proc->p_sysent->sv_imgact_try) != NULL) error = img_first(imgp); /* * Loop through the list of image activators, calling each one. * An activator returns -1 if there is no match, 0 on success, * and an error otherwise. */ for (i = 0; error == -1 && execsw[i]; ++i) { if (execsw[i]->ex_imgact == NULL || execsw[i]->ex_imgact == img_first) { continue; } error = (*execsw[i]->ex_imgact)(imgp); } if (error) { if (error == -1) { if (textset == 0) VOP_UNSET_TEXT(imgp->vp); error = ENOEXEC; } goto exec_fail_dealloc; } /* * Special interpreter operation, cleanup and loop up to try to * activate the interpreter. */ if (imgp->interpreted) { exec_unmap_first_page(imgp); /* * VV_TEXT needs to be unset for scripts. There is a short * period before we determine that something is a script where * VV_TEXT will be set. The vnode lock is held over this * entire period so nothing should illegitimately be blocked. */ VOP_UNSET_TEXT(imgp->vp); /* free name buffer and old vnode */ if (args->fname != NULL) NDFREE(&nd, NDF_ONLY_PNBUF); #ifdef MAC mac_execve_interpreter_enter(binvp, &interpvplabel); #endif if (imgp->opened) { VOP_CLOSE(binvp, FREAD, td->td_ucred, td); imgp->opened = 0; } vput(binvp); vm_object_deallocate(imgp->object); imgp->object = NULL; /* set new name to that of the interpreter */ NDINIT(&nd, LOOKUP, LOCKLEAF | FOLLOW | SAVENAME, UIO_SYSSPACE, imgp->interpreter_name, td); args->fname = imgp->interpreter_name; goto interpret; } /* * NB: We unlock the vnode here because it is believed that none * of the sv_copyout_strings/sv_fixup operations require the vnode. */ VOP_UNLOCK(imgp->vp, 0); /* * Do the best to calculate the full path to the image file. */ if (imgp->auxargs != NULL && ((args->fname != NULL && args->fname[0] == '/') || vn_fullpath(td, imgp->vp, &imgp->execpath, &imgp->freepath) != 0)) imgp->execpath = args->fname; if (disallow_high_osrel && P_OSREL_MAJOR(p->p_osrel) > P_OSREL_MAJOR(__FreeBSD_version)) { error = ENOEXEC; uprintf("Osrel %d for image %s too high\n", p->p_osrel, imgp->execpath != NULL ? imgp->execpath : ""); vn_lock(imgp->vp, LK_SHARED | LK_RETRY); goto exec_fail_dealloc; } /* * Copy out strings (args and env) and initialize stack base */ if (p->p_sysent->sv_copyout_strings) stack_base = (*p->p_sysent->sv_copyout_strings)(imgp); else stack_base = exec_copyout_strings(imgp); /* * If custom stack fixup routine present for this process * let it do the stack setup. * Else stuff argument count as first item on stack */ if (p->p_sysent->sv_fixup != NULL) (*p->p_sysent->sv_fixup)(&stack_base, imgp); else suword(--stack_base, imgp->args->argc); /* * For security and other reasons, the file descriptor table cannot * be shared after an exec. */ fdunshare(td); /* close files on exec */ fdcloseexec(td); /* * Malloc things before we need locks. */ newcred = crget(); euip = uifind(attr.va_uid); i = imgp->args->begin_envv - imgp->args->begin_argv; /* Cache arguments if they fit inside our allowance */ if (ps_arg_cache_limit >= i + sizeof(struct pargs)) { newargs = pargs_alloc(i); bcopy(imgp->args->begin_argv, newargs->ar_args, i); } vn_lock(imgp->vp, LK_SHARED | LK_RETRY); /* Get a reference to the vnode prior to locking the proc */ VREF(binvp); /* * For security and other reasons, signal handlers cannot * be shared after an exec. The new process gets a copy of the old * handlers. In execsigs(), the new process will have its signals * reset. */ - PROC_LOCK(p); - oldcred = crcopysafe(p, newcred); if (sigacts_shared(p->p_sigacts)) { oldsigacts = p->p_sigacts; - PROC_UNLOCK(p); newsigacts = sigacts_alloc(); sigacts_copy(newsigacts, oldsigacts); - PROC_LOCK(p); - p->p_sigacts = newsigacts; } else oldsigacts = NULL; + PROC_LOCK(p); + if (oldsigacts) + p->p_sigacts = newsigacts; + oldcred = crcopysafe(p, newcred); /* Stop profiling */ stopprofclock(p); /* reset caught signals */ execsigs(p); /* name this process - nameiexec(p, ndp) */ bzero(p->p_comm, sizeof(p->p_comm)); if (args->fname) bcopy(nd.ni_cnd.cn_nameptr, p->p_comm, min(nd.ni_cnd.cn_namelen, MAXCOMLEN)); else if (vn_commname(binvp, p->p_comm, sizeof(p->p_comm)) != 0) bcopy(fexecv_proc_title, p->p_comm, sizeof(fexecv_proc_title)); bcopy(p->p_comm, td->td_name, sizeof(td->td_name)); #ifdef KTR sched_clear_tdname(td); #endif /* * mark as execed, wakeup the process that vforked (if any) and tell * it that it now has its own resources back */ p->p_flag |= P_EXEC; if (p->p_pptr && (p->p_flag & P_PPWAIT)) { p->p_flag &= ~(P_PPWAIT | P_PPTRACE); cv_broadcast(&p->p_pwait); } /* * Implement image setuid/setgid. * * Don't honor setuid/setgid if the filesystem prohibits it or if * the process is being traced. * * We disable setuid/setgid/etc in compatibility mode on the basis * that most setugid applications are not written with that * environment in mind, and will therefore almost certainly operate * incorrectly. In principle there's no reason that setugid * applications might not be useful in capability mode, so we may want * to reconsider this conservative design choice in the future. * * XXXMAC: For the time being, use NOSUID to also prohibit * transitions on the file system. */ credential_changing = 0; credential_changing |= (attr.va_mode & S_ISUID) && oldcred->cr_uid != attr.va_uid; credential_changing |= (attr.va_mode & S_ISGID) && oldcred->cr_gid != attr.va_gid; #ifdef MAC will_transition = mac_vnode_execve_will_transition(oldcred, imgp->vp, interpvplabel, imgp); credential_changing |= will_transition; #endif if (credential_changing && #ifdef CAPABILITY_MODE ((oldcred->cr_flags & CRED_FLAG_CAPMODE) == 0) && #endif (imgp->vp->v_mount->mnt_flag & MNT_NOSUID) == 0 && (p->p_flag & P_TRACED) == 0) { /* * Turn off syscall tracing for set-id programs, except for * root. Record any set-id flags first to make sure that * we do not regain any tracing during a possible block. */ setsugid(p); #ifdef KTRACE if (p->p_tracecred != NULL && priv_check_cred(p->p_tracecred, PRIV_DEBUG_DIFFCRED, 0)) ktrprocexec(p, &tracecred, &tracevp); #endif /* * Close any file descriptors 0..2 that reference procfs, * then make sure file descriptors 0..2 are in use. * * setugidsafety() may call closef() and then pfind() * which may grab the process lock. * fdcheckstd() may call falloc() which may block to * allocate memory, so temporarily drop the process lock. */ PROC_UNLOCK(p); VOP_UNLOCK(imgp->vp, 0); setugidsafety(td); error = fdcheckstd(td); vn_lock(imgp->vp, LK_SHARED | LK_RETRY); if (error != 0) goto done1; PROC_LOCK(p); /* * Set the new credentials. */ if (attr.va_mode & S_ISUID) change_euid(newcred, euip); if (attr.va_mode & S_ISGID) change_egid(newcred, attr.va_gid); #ifdef MAC if (will_transition) { mac_vnode_execve_transition(oldcred, newcred, imgp->vp, interpvplabel, imgp); } #endif /* * Implement correct POSIX saved-id behavior. * * XXXMAC: Note that the current logic will save the * uid and gid if a MAC domain transition occurs, even * though maybe it shouldn't. */ change_svuid(newcred, newcred->cr_uid); change_svgid(newcred, newcred->cr_gid); p->p_ucred = newcred; newcred = NULL; } else { if (oldcred->cr_uid == oldcred->cr_ruid && oldcred->cr_gid == oldcred->cr_rgid) p->p_flag &= ~P_SUGID; /* * Implement correct POSIX saved-id behavior. * * XXX: It's not clear that the existing behavior is * POSIX-compliant. A number of sources indicate that the * saved uid/gid should only be updated if the new ruid is * not equal to the old ruid, or the new euid is not equal * to the old euid and the new euid is not equal to the old * ruid. The FreeBSD code always updates the saved uid/gid. * Also, this code uses the new (replaced) euid and egid as * the source, which may or may not be the right ones to use. */ if (oldcred->cr_svuid != oldcred->cr_uid || oldcred->cr_svgid != oldcred->cr_gid) { change_svuid(newcred, newcred->cr_uid); change_svgid(newcred, newcred->cr_gid); p->p_ucred = newcred; newcred = NULL; } } /* * Store the vp for use in procfs. This vnode was referenced prior * to locking the proc lock. */ textvp = p->p_textvp; p->p_textvp = binvp; #ifdef KDTRACE_HOOKS /* * Tell the DTrace fasttrap provider about the exec if it * has declared an interest. */ if (dtrace_fasttrap_exec) dtrace_fasttrap_exec(p); #endif /* * Notify others that we exec'd, and clear the P_INEXEC flag * as we're now a bona fide freshly-execed process. */ KNOTE_LOCKED(&p->p_klist, NOTE_EXEC); p->p_flag &= ~P_INEXEC; /* clear "fork but no exec" flag, as we _are_ execing */ p->p_acflag &= ~AFORK; /* * Free any previous argument cache and replace it with * the new argument cache, if any. */ oldargs = p->p_args; p->p_args = newargs; newargs = NULL; #ifdef HWPMC_HOOKS /* * Check if system-wide sampling is in effect or if the * current process is using PMCs. If so, do exec() time * processing. This processing needs to happen AFTER the * P_INEXEC flag is cleared. * * The proc lock needs to be released before taking the PMC * SX. */ if (PMC_SYSTEM_SAMPLING_ACTIVE() || PMC_PROC_IS_USING_PMCS(p)) { PROC_UNLOCK(p); VOP_UNLOCK(imgp->vp, 0); pe.pm_credentialschanged = credential_changing; pe.pm_entryaddr = imgp->entry_addr; PMC_CALL_HOOK_X(td, PMC_FN_PROCESS_EXEC, (void *) &pe); vn_lock(imgp->vp, LK_SHARED | LK_RETRY); } else PROC_UNLOCK(p); #else /* !HWPMC_HOOKS */ PROC_UNLOCK(p); #endif /* Set values passed into the program in registers. */ if (p->p_sysent->sv_setregs) (*p->p_sysent->sv_setregs)(td, imgp, (u_long)(uintptr_t)stack_base); else exec_setregs(td, imgp, (u_long)(uintptr_t)stack_base); vfs_mark_atime(imgp->vp, td->td_ucred); SDT_PROBE(proc, kernel, , exec__success, args->fname, 0, 0, 0, 0); done1: /* * Free any resources malloc'd earlier that we didn't use. */ uifree(euip); if (newcred == NULL) crfree(oldcred); else crfree(newcred); VOP_UNLOCK(imgp->vp, 0); /* * Handle deferred decrement of ref counts. */ if (textvp != NULL) vrele(textvp); if (binvp && error != 0) vrele(binvp); #ifdef KTRACE if (tracevp != NULL) vrele(tracevp); if (tracecred != NULL) crfree(tracecred); #endif vn_lock(imgp->vp, LK_SHARED | LK_RETRY); pargs_drop(oldargs); pargs_drop(newargs); if (oldsigacts != NULL) sigacts_free(oldsigacts); exec_fail_dealloc: /* * free various allocated resources */ if (imgp->firstpage != NULL) exec_unmap_first_page(imgp); if (imgp->vp != NULL) { if (args->fname) NDFREE(&nd, NDF_ONLY_PNBUF); if (imgp->opened) VOP_CLOSE(imgp->vp, FREAD, td->td_ucred, td); vput(imgp->vp); } if (imgp->object != NULL) vm_object_deallocate(imgp->object); free(imgp->freepath, M_TEMP); if (error == 0) { PROC_LOCK(p); td->td_dbgflags |= TDB_EXEC; PROC_UNLOCK(p); /* * Stop the process here if its stop event mask has * the S_EXEC bit set. */ STOPEVENT(p, S_EXEC, 0); goto done2; } exec_fail: /* we're done here, clear P_INEXEC */ PROC_LOCK(p); p->p_flag &= ~P_INEXEC; PROC_UNLOCK(p); SDT_PROBE(proc, kernel, , exec__failure, error, 0, 0, 0, 0); done2: #ifdef MAC mac_execve_exit(imgp); mac_execve_interpreter_exit(interpvplabel); #endif exec_free_args(args); if (error && imgp->vmspace_destroyed) { /* sorry, no more process anymore. exit gracefully */ exit1(td, W_EXITCODE(0, SIGABRT)); /* NOT REACHED */ } #ifdef KTRACE if (error == 0) ktrprocctor(p); #endif return (error); } int exec_map_first_page(imgp) struct image_params *imgp; { int rv, i; int initial_pagein; vm_page_t ma[VM_INITIAL_PAGEIN]; vm_object_t object; if (imgp->firstpage != NULL) exec_unmap_first_page(imgp); object = imgp->vp->v_object; if (object == NULL) return (EACCES); VM_OBJECT_WLOCK(object); #if VM_NRESERVLEVEL > 0 if ((object->flags & OBJ_COLORED) == 0) { object->flags |= OBJ_COLORED; object->pg_color = 0; } #endif ma[0] = vm_page_grab(object, 0, VM_ALLOC_NORMAL); if (ma[0]->valid != VM_PAGE_BITS_ALL) { initial_pagein = VM_INITIAL_PAGEIN; if (initial_pagein > object->size) initial_pagein = object->size; for (i = 1; i < initial_pagein; i++) { if ((ma[i] = vm_page_next(ma[i - 1])) != NULL) { if (ma[i]->valid) break; if (vm_page_tryxbusy(ma[i])) break; } else { ma[i] = vm_page_alloc(object, i, VM_ALLOC_NORMAL | VM_ALLOC_IFNOTCACHED); if (ma[i] == NULL) break; } } initial_pagein = i; rv = vm_pager_get_pages(object, ma, initial_pagein, 0); ma[0] = vm_page_lookup(object, 0); if ((rv != VM_PAGER_OK) || (ma[0] == NULL)) { if (ma[0] != NULL) { vm_page_lock(ma[0]); vm_page_free(ma[0]); vm_page_unlock(ma[0]); } VM_OBJECT_WUNLOCK(object); return (EIO); } } vm_page_xunbusy(ma[0]); vm_page_lock(ma[0]); vm_page_hold(ma[0]); vm_page_unlock(ma[0]); VM_OBJECT_WUNLOCK(object); imgp->firstpage = sf_buf_alloc(ma[0], 0); imgp->image_header = (char *)sf_buf_kva(imgp->firstpage); return (0); } void exec_unmap_first_page(imgp) struct image_params *imgp; { vm_page_t m; if (imgp->firstpage != NULL) { m = sf_buf_page(imgp->firstpage); sf_buf_free(imgp->firstpage); imgp->firstpage = NULL; vm_page_lock(m); vm_page_unhold(m); vm_page_unlock(m); } } /* * Destroy old address space, and allocate a new stack * The new stack is only SGROWSIZ large because it is grown * automatically in trap.c. */ int exec_new_vmspace(imgp, sv) struct image_params *imgp; struct sysentvec *sv; { int error; struct proc *p = imgp->proc; struct vmspace *vmspace = p->p_vmspace; vm_object_t obj; vm_offset_t sv_minuser, stack_addr; vm_map_t map; u_long ssiz; imgp->vmspace_destroyed = 1; imgp->sysent = sv; /* May be called with Giant held */ EVENTHANDLER_INVOKE(process_exec, p, imgp); /* * Blow away entire process VM, if address space not shared, * otherwise, create a new VM space so that other threads are * not disrupted */ map = &vmspace->vm_map; if (map_at_zero) sv_minuser = sv->sv_minuser; else sv_minuser = MAX(sv->sv_minuser, PAGE_SIZE); if (vmspace->vm_refcnt == 1 && vm_map_min(map) == sv_minuser && vm_map_max(map) == sv->sv_maxuser) { shmexit(vmspace); pmap_remove_pages(vmspace_pmap(vmspace)); vm_map_remove(map, vm_map_min(map), vm_map_max(map)); } else { error = vmspace_exec(p, sv_minuser, sv->sv_maxuser); if (error) return (error); vmspace = p->p_vmspace; map = &vmspace->vm_map; } /* Map a shared page */ obj = sv->sv_shared_page_obj; if (obj != NULL) { vm_object_reference(obj); error = vm_map_fixed(map, obj, 0, sv->sv_shared_page_base, sv->sv_shared_page_len, VM_PROT_READ | VM_PROT_EXECUTE, VM_PROT_READ | VM_PROT_EXECUTE, MAP_INHERIT_SHARE | MAP_ACC_NO_CHARGE); if (error) { vm_object_deallocate(obj); return (error); } } /* Allocate a new stack */ if (sv->sv_maxssiz != NULL) ssiz = *sv->sv_maxssiz; else ssiz = maxssiz; stack_addr = sv->sv_usrstack - ssiz; error = vm_map_stack(map, stack_addr, (vm_size_t)ssiz, obj != NULL && imgp->stack_prot != 0 ? imgp->stack_prot : sv->sv_stackprot, VM_PROT_ALL, MAP_STACK_GROWS_DOWN); if (error) return (error); #ifdef __ia64__ /* Allocate a new register stack */ stack_addr = IA64_BACKINGSTORE; error = vm_map_stack(map, stack_addr, (vm_size_t)ssiz, sv->sv_stackprot, VM_PROT_ALL, MAP_STACK_GROWS_UP); if (error) return (error); #endif /* vm_ssize and vm_maxsaddr are somewhat antiquated concepts in the * VM_STACK case, but they are still used to monitor the size of the * process stack so we can check the stack rlimit. */ vmspace->vm_ssize = sgrowsiz >> PAGE_SHIFT; vmspace->vm_maxsaddr = (char *)sv->sv_usrstack - ssiz; return (0); } /* * Copy out argument and environment strings from the old process address * space into the temporary string buffer. */ int exec_copyin_args(struct image_args *args, char *fname, enum uio_seg segflg, char **argv, char **envv) { char *argp, *envp; int error; size_t length; bzero(args, sizeof(*args)); if (argv == NULL) return (EFAULT); /* * Allocate demand-paged memory for the file name, argument, and * environment strings. */ error = exec_alloc_args(args); if (error != 0) return (error); /* * Copy the file name. */ if (fname != NULL) { args->fname = args->buf; error = (segflg == UIO_SYSSPACE) ? copystr(fname, args->fname, PATH_MAX, &length) : copyinstr(fname, args->fname, PATH_MAX, &length); if (error != 0) goto err_exit; } else length = 0; args->begin_argv = args->buf + length; args->endp = args->begin_argv; args->stringspace = ARG_MAX; /* * extract arguments first */ while ((argp = (caddr_t) (intptr_t) fuword(argv++))) { if (argp == (caddr_t) -1) { error = EFAULT; goto err_exit; } if ((error = copyinstr(argp, args->endp, args->stringspace, &length))) { if (error == ENAMETOOLONG) error = E2BIG; goto err_exit; } args->stringspace -= length; args->endp += length; args->argc++; } args->begin_envv = args->endp; /* * extract environment strings */ if (envv) { while ((envp = (caddr_t)(intptr_t)fuword(envv++))) { if (envp == (caddr_t)-1) { error = EFAULT; goto err_exit; } if ((error = copyinstr(envp, args->endp, args->stringspace, &length))) { if (error == ENAMETOOLONG) error = E2BIG; goto err_exit; } args->stringspace -= length; args->endp += length; args->envc++; } } return (0); err_exit: exec_free_args(args); return (error); } /* * Allocate temporary demand-paged, zero-filled memory for the file name, * argument, and environment strings. Returns zero if the allocation succeeds * and ENOMEM otherwise. */ int exec_alloc_args(struct image_args *args) { args->buf = (char *)kmap_alloc_wait(exec_map, PATH_MAX + ARG_MAX); return (args->buf != NULL ? 0 : ENOMEM); } void exec_free_args(struct image_args *args) { if (args->buf != NULL) { kmap_free_wakeup(exec_map, (vm_offset_t)args->buf, PATH_MAX + ARG_MAX); args->buf = NULL; } if (args->fname_buf != NULL) { free(args->fname_buf, M_TEMP); args->fname_buf = NULL; } } /* * Copy strings out to the new process address space, constructing new arg * and env vector tables. Return a pointer to the base so that it can be used * as the initial stack pointer. */ register_t * exec_copyout_strings(imgp) struct image_params *imgp; { int argc, envc; char **vectp; char *stringp; uintptr_t destp; register_t *stack_base; struct ps_strings *arginfo; struct proc *p; size_t execpath_len; int szsigcode, szps; char canary[sizeof(long) * 8]; szps = sizeof(pagesizes[0]) * MAXPAGESIZES; /* * Calculate string base and vector table pointers. * Also deal with signal trampoline code for this exec type. */ if (imgp->execpath != NULL && imgp->auxargs != NULL) execpath_len = strlen(imgp->execpath) + 1; else execpath_len = 0; p = imgp->proc; szsigcode = 0; arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; if (p->p_sysent->sv_sigcode_base == 0) { if (p->p_sysent->sv_szsigcode != NULL) szsigcode = *(p->p_sysent->sv_szsigcode); } destp = (uintptr_t)arginfo; /* * install sigcode */ if (szsigcode != 0) { destp -= szsigcode; destp = rounddown2(destp, sizeof(void *)); copyout(p->p_sysent->sv_sigcode, (void *)destp, szsigcode); } /* * Copy the image path for the rtld. */ if (execpath_len != 0) { destp -= execpath_len; imgp->execpathp = destp; copyout(imgp->execpath, (void *)destp, execpath_len); } /* * Prepare the canary for SSP. */ arc4rand(canary, sizeof(canary), 0); destp -= sizeof(canary); imgp->canary = destp; copyout(canary, (void *)destp, sizeof(canary)); imgp->canarylen = sizeof(canary); /* * Prepare the pagesizes array. */ destp -= szps; destp = rounddown2(destp, sizeof(void *)); imgp->pagesizes = destp; copyout(pagesizes, (void *)destp, szps); imgp->pagesizeslen = szps; destp -= ARG_MAX - imgp->args->stringspace; destp = rounddown2(destp, sizeof(void *)); /* * If we have a valid auxargs ptr, prepare some room * on the stack. */ if (imgp->auxargs) { /* * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for * lower compatibility. */ imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size : (AT_COUNT * 2); /* * The '+ 2' is for the null pointers at the end of each of * the arg and env vector sets,and imgp->auxarg_size is room * for argument of Runtime loader. */ vectp = (char **)(destp - (imgp->args->argc + imgp->args->envc + 2 + imgp->auxarg_size) * sizeof(char *)); } else { /* * The '+ 2' is for the null pointers at the end of each of * the arg and env vector sets */ vectp = (char **)(destp - (imgp->args->argc + imgp->args->envc + 2) * sizeof(char *)); } /* * vectp also becomes our initial stack base */ stack_base = (register_t *)vectp; stringp = imgp->args->begin_argv; argc = imgp->args->argc; envc = imgp->args->envc; /* * Copy out strings - arguments and environment. */ copyout(stringp, (void *)destp, ARG_MAX - imgp->args->stringspace); /* * Fill in "ps_strings" struct for ps, w, etc. */ suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); suword32(&arginfo->ps_nargvstr, argc); /* * Fill in argument portion of vector table. */ for (; argc > 0; --argc) { suword(vectp++, (long)(intptr_t)destp); while (*stringp++ != 0) destp++; destp++; } /* a null vector table pointer separates the argp's from the envp's */ suword(vectp++, 0); suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); suword32(&arginfo->ps_nenvstr, envc); /* * Fill in environment portion of vector table. */ for (; envc > 0; --envc) { suword(vectp++, (long)(intptr_t)destp); while (*stringp++ != 0) destp++; destp++; } /* end of vector table is a null pointer */ suword(vectp, 0); return (stack_base); } /* * Check permissions of file to execute. * Called with imgp->vp locked. * Return 0 for success or error code on failure. */ int exec_check_permissions(imgp) struct image_params *imgp; { struct vnode *vp = imgp->vp; struct vattr *attr = imgp->attr; struct thread *td; int error, writecount; td = curthread; /* Get file attributes */ error = VOP_GETATTR(vp, attr, td->td_ucred); if (error) return (error); #ifdef MAC error = mac_vnode_check_exec(td->td_ucred, imgp->vp, imgp); if (error) return (error); #endif /* * 1) Check if file execution is disabled for the filesystem that * this file resides on. * 2) Ensure that at least one execute bit is on. Otherwise, a * privileged user will always succeed, and we don't want this * to happen unless the file really is executable. * 3) Ensure that the file is a regular file. */ if ((vp->v_mount->mnt_flag & MNT_NOEXEC) || (attr->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0 || (attr->va_type != VREG)) return (EACCES); /* * Zero length files can't be exec'd */ if (attr->va_size == 0) return (ENOEXEC); /* * Check for execute permission to file based on current credentials. */ error = VOP_ACCESS(vp, VEXEC, td->td_ucred, td); if (error) return (error); /* * Check number of open-for-writes on the file and deny execution * if there are any. */ error = VOP_GET_WRITECOUNT(vp, &writecount); if (error != 0) return (error); if (writecount != 0) return (ETXTBSY); /* * Call filesystem specific open routine (which does nothing in the * general case). */ error = VOP_OPEN(vp, FREAD, td->td_ucred, td, NULL); if (error == 0) imgp->opened = 1; return (error); } /* * Exec handler registration */ int exec_register(execsw_arg) const struct execsw *execsw_arg; { const struct execsw **es, **xs, **newexecsw; int count = 2; /* New slot and trailing NULL */ if (execsw) for (es = execsw; *es; es++) count++; newexecsw = malloc(count * sizeof(*es), M_TEMP, M_WAITOK); if (newexecsw == NULL) return (ENOMEM); xs = newexecsw; if (execsw) for (es = execsw; *es; es++) *xs++ = *es; *xs++ = execsw_arg; *xs = NULL; if (execsw) free(execsw, M_TEMP); execsw = newexecsw; return (0); } int exec_unregister(execsw_arg) const struct execsw *execsw_arg; { const struct execsw **es, **xs, **newexecsw; int count = 1; if (execsw == NULL) panic("unregister with no handlers left?\n"); for (es = execsw; *es; es++) { if (*es == execsw_arg) break; } if (*es == NULL) return (ENOENT); for (es = execsw; *es; es++) if (*es != execsw_arg) count++; newexecsw = malloc(count * sizeof(*es), M_TEMP, M_WAITOK); if (newexecsw == NULL) return (ENOMEM); xs = newexecsw; for (es = execsw; *es; es++) if (*es != execsw_arg) *xs++ = *es; *xs = NULL; if (execsw) free(execsw, M_TEMP); execsw = newexecsw; return (0); } Index: stable/10/sys/kern/kern_sig.c =================================================================== --- stable/10/sys/kern/kern_sig.c (revision 270083) +++ stable/10/sys/kern/kern_sig.c (revision 270084) @@ -1,3472 +1,3468 @@ /*- * 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_sig.c 8.7 (Berkeley) 4/18/94 */ #include __FBSDID("$FreeBSD$"); #include "opt_compat.h" #include "opt_kdtrace.h" #include "opt_ktrace.h" #include "opt_core.h" #include "opt_procdesc.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */ SDT_PROVIDER_DECLARE(proc); SDT_PROBE_DEFINE3(proc, kernel, , signal__send, "struct thread *", "struct proc *", "int"); SDT_PROBE_DEFINE2(proc, kernel, , signal__clear, "int", "ksiginfo_t *"); SDT_PROBE_DEFINE3(proc, kernel, , signal__discard, "struct thread *", "struct proc *", "int"); static int coredump(struct thread *); static int killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi); static int issignal(struct thread *td); static int sigprop(int sig); static void tdsigwakeup(struct thread *, int, sig_t, int); static void sig_suspend_threads(struct thread *, struct proc *, int); static int filt_sigattach(struct knote *kn); static void filt_sigdetach(struct knote *kn); static int filt_signal(struct knote *kn, long hint); static struct thread *sigtd(struct proc *p, int sig, int prop); static void sigqueue_start(void); static uma_zone_t ksiginfo_zone = NULL; struct filterops sig_filtops = { .f_isfd = 0, .f_attach = filt_sigattach, .f_detach = filt_sigdetach, .f_event = filt_signal, }; static int kern_logsigexit = 1; SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW, &kern_logsigexit, 0, "Log processes quitting on abnormal signals to syslog(3)"); static int kern_forcesigexit = 1; SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW, &kern_forcesigexit, 0, "Force trap signal to be handled"); static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0, "POSIX real time signal"); static int max_pending_per_proc = 128; SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW, &max_pending_per_proc, 0, "Max pending signals per proc"); static int preallocate_siginfo = 1024; TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo); SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD, &preallocate_siginfo, 0, "Preallocated signal memory size"); static int signal_overflow = 0; SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD, &signal_overflow, 0, "Number of signals overflew"); static int signal_alloc_fail = 0; SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD, &signal_alloc_fail, 0, "signals failed to be allocated"); SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL); /* * Policy -- Can ucred cr1 send SIGIO to process cr2? * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG * in the right situations. */ #define CANSIGIO(cr1, cr2) \ ((cr1)->cr_uid == 0 || \ (cr1)->cr_ruid == (cr2)->cr_ruid || \ (cr1)->cr_uid == (cr2)->cr_ruid || \ (cr1)->cr_ruid == (cr2)->cr_uid || \ (cr1)->cr_uid == (cr2)->cr_uid) static int sugid_coredump; TUNABLE_INT("kern.sugid_coredump", &sugid_coredump); SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW, &sugid_coredump, 0, "Allow setuid and setgid processes to dump core"); static int capmode_coredump; TUNABLE_INT("kern.capmode_coredump", &capmode_coredump); SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RW, &capmode_coredump, 0, "Allow processes in capability mode to dump core"); static int do_coredump = 1; SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW, &do_coredump, 0, "Enable/Disable coredumps"); static int set_core_nodump_flag = 0; SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag, 0, "Enable setting the NODUMP flag on coredump files"); /* * Signal properties and actions. * The array below categorizes the signals and their default actions * according to the following properties: */ #define SA_KILL 0x01 /* terminates process by default */ #define SA_CORE 0x02 /* ditto and coredumps */ #define SA_STOP 0x04 /* suspend process */ #define SA_TTYSTOP 0x08 /* ditto, from tty */ #define SA_IGNORE 0x10 /* ignore by default */ #define SA_CONT 0x20 /* continue if suspended */ #define SA_CANTMASK 0x40 /* non-maskable, catchable */ static int sigproptbl[NSIG] = { SA_KILL, /* SIGHUP */ SA_KILL, /* SIGINT */ SA_KILL|SA_CORE, /* SIGQUIT */ SA_KILL|SA_CORE, /* SIGILL */ SA_KILL|SA_CORE, /* SIGTRAP */ SA_KILL|SA_CORE, /* SIGABRT */ SA_KILL|SA_CORE, /* SIGEMT */ SA_KILL|SA_CORE, /* SIGFPE */ SA_KILL, /* SIGKILL */ SA_KILL|SA_CORE, /* SIGBUS */ SA_KILL|SA_CORE, /* SIGSEGV */ SA_KILL|SA_CORE, /* SIGSYS */ SA_KILL, /* SIGPIPE */ SA_KILL, /* SIGALRM */ SA_KILL, /* SIGTERM */ SA_IGNORE, /* SIGURG */ SA_STOP, /* SIGSTOP */ SA_STOP|SA_TTYSTOP, /* SIGTSTP */ SA_IGNORE|SA_CONT, /* SIGCONT */ SA_IGNORE, /* SIGCHLD */ SA_STOP|SA_TTYSTOP, /* SIGTTIN */ SA_STOP|SA_TTYSTOP, /* SIGTTOU */ SA_IGNORE, /* SIGIO */ SA_KILL, /* SIGXCPU */ SA_KILL, /* SIGXFSZ */ SA_KILL, /* SIGVTALRM */ SA_KILL, /* SIGPROF */ SA_IGNORE, /* SIGWINCH */ SA_IGNORE, /* SIGINFO */ SA_KILL, /* SIGUSR1 */ SA_KILL, /* SIGUSR2 */ }; static void reschedule_signals(struct proc *p, sigset_t block, int flags); static void sigqueue_start(void) { ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); uma_prealloc(ksiginfo_zone, preallocate_siginfo); p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS); p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1); p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc); } ksiginfo_t * ksiginfo_alloc(int wait) { int flags; flags = M_ZERO; if (! wait) flags |= M_NOWAIT; if (ksiginfo_zone != NULL) return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags)); return (NULL); } void ksiginfo_free(ksiginfo_t *ksi) { uma_zfree(ksiginfo_zone, ksi); } static __inline int ksiginfo_tryfree(ksiginfo_t *ksi) { if (!(ksi->ksi_flags & KSI_EXT)) { uma_zfree(ksiginfo_zone, ksi); return (1); } return (0); } void sigqueue_init(sigqueue_t *list, struct proc *p) { SIGEMPTYSET(list->sq_signals); SIGEMPTYSET(list->sq_kill); TAILQ_INIT(&list->sq_list); list->sq_proc = p; list->sq_flags = SQ_INIT; } /* * Get a signal's ksiginfo. * Return: * 0 - signal not found * others - signal number */ static int sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si) { struct proc *p = sq->sq_proc; struct ksiginfo *ksi, *next; int count = 0; KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited")); if (!SIGISMEMBER(sq->sq_signals, signo)) return (0); if (SIGISMEMBER(sq->sq_kill, signo)) { count++; SIGDELSET(sq->sq_kill, signo); } TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) { if (ksi->ksi_signo == signo) { if (count == 0) { TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link); ksi->ksi_sigq = NULL; ksiginfo_copy(ksi, si); if (ksiginfo_tryfree(ksi) && p != NULL) p->p_pendingcnt--; } if (++count > 1) break; } } if (count <= 1) SIGDELSET(sq->sq_signals, signo); si->ksi_signo = signo; return (signo); } void sigqueue_take(ksiginfo_t *ksi) { struct ksiginfo *kp; struct proc *p; sigqueue_t *sq; if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL) return; p = sq->sq_proc; TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link); ksi->ksi_sigq = NULL; if (!(ksi->ksi_flags & KSI_EXT) && p != NULL) p->p_pendingcnt--; for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL; kp = TAILQ_NEXT(kp, ksi_link)) { if (kp->ksi_signo == ksi->ksi_signo) break; } if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo)) SIGDELSET(sq->sq_signals, ksi->ksi_signo); } static int sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si) { struct proc *p = sq->sq_proc; struct ksiginfo *ksi; int ret = 0; KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited")); if (signo == SIGKILL || signo == SIGSTOP || si == NULL) { SIGADDSET(sq->sq_kill, signo); goto out_set_bit; } /* directly insert the ksi, don't copy it */ if (si->ksi_flags & KSI_INS) { if (si->ksi_flags & KSI_HEAD) TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link); else TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link); si->ksi_sigq = sq; goto out_set_bit; } if (__predict_false(ksiginfo_zone == NULL)) { SIGADDSET(sq->sq_kill, signo); goto out_set_bit; } if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) { signal_overflow++; ret = EAGAIN; } else if ((ksi = ksiginfo_alloc(0)) == NULL) { signal_alloc_fail++; ret = EAGAIN; } else { if (p != NULL) p->p_pendingcnt++; ksiginfo_copy(si, ksi); ksi->ksi_signo = signo; if (si->ksi_flags & KSI_HEAD) TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link); else TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link); ksi->ksi_sigq = sq; } if ((si->ksi_flags & KSI_TRAP) != 0 || (si->ksi_flags & KSI_SIGQ) == 0) { if (ret != 0) SIGADDSET(sq->sq_kill, signo); ret = 0; goto out_set_bit; } if (ret != 0) return (ret); out_set_bit: SIGADDSET(sq->sq_signals, signo); return (ret); } void sigqueue_flush(sigqueue_t *sq) { struct proc *p = sq->sq_proc; ksiginfo_t *ksi; KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited")); if (p != NULL) PROC_LOCK_ASSERT(p, MA_OWNED); while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) { TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link); ksi->ksi_sigq = NULL; if (ksiginfo_tryfree(ksi) && p != NULL) p->p_pendingcnt--; } SIGEMPTYSET(sq->sq_signals); SIGEMPTYSET(sq->sq_kill); } static void sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set) { sigset_t tmp; struct proc *p1, *p2; ksiginfo_t *ksi, *next; KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited")); KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited")); p1 = src->sq_proc; p2 = dst->sq_proc; /* Move siginfo to target list */ TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) { if (SIGISMEMBER(*set, ksi->ksi_signo)) { TAILQ_REMOVE(&src->sq_list, ksi, ksi_link); if (p1 != NULL) p1->p_pendingcnt--; TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link); ksi->ksi_sigq = dst; if (p2 != NULL) p2->p_pendingcnt++; } } /* Move pending bits to target list */ tmp = src->sq_kill; SIGSETAND(tmp, *set); SIGSETOR(dst->sq_kill, tmp); SIGSETNAND(src->sq_kill, tmp); tmp = src->sq_signals; SIGSETAND(tmp, *set); SIGSETOR(dst->sq_signals, tmp); SIGSETNAND(src->sq_signals, tmp); } #if 0 static void sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo) { sigset_t set; SIGEMPTYSET(set); SIGADDSET(set, signo); sigqueue_move_set(src, dst, &set); } #endif static void sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set) { struct proc *p = sq->sq_proc; ksiginfo_t *ksi, *next; KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited")); /* Remove siginfo queue */ TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) { if (SIGISMEMBER(*set, ksi->ksi_signo)) { TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link); ksi->ksi_sigq = NULL; if (ksiginfo_tryfree(ksi) && p != NULL) p->p_pendingcnt--; } } SIGSETNAND(sq->sq_kill, *set); SIGSETNAND(sq->sq_signals, *set); } void sigqueue_delete(sigqueue_t *sq, int signo) { sigset_t set; SIGEMPTYSET(set); SIGADDSET(set, signo); sigqueue_delete_set(sq, &set); } /* Remove a set of signals for a process */ static void sigqueue_delete_set_proc(struct proc *p, const sigset_t *set) { sigqueue_t worklist; struct thread *td0; PROC_LOCK_ASSERT(p, MA_OWNED); sigqueue_init(&worklist, NULL); sigqueue_move_set(&p->p_sigqueue, &worklist, set); FOREACH_THREAD_IN_PROC(p, td0) sigqueue_move_set(&td0->td_sigqueue, &worklist, set); sigqueue_flush(&worklist); } void sigqueue_delete_proc(struct proc *p, int signo) { sigset_t set; SIGEMPTYSET(set); SIGADDSET(set, signo); sigqueue_delete_set_proc(p, &set); } static void sigqueue_delete_stopmask_proc(struct proc *p) { sigset_t set; SIGEMPTYSET(set); SIGADDSET(set, SIGSTOP); SIGADDSET(set, SIGTSTP); SIGADDSET(set, SIGTTIN); SIGADDSET(set, SIGTTOU); sigqueue_delete_set_proc(p, &set); } /* * Determine signal that should be delivered to thread td, the current * thread, 0 if none. If there is a pending stop signal with default * action, the process stops in issignal(). */ int cursig(struct thread *td) { PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED); THREAD_LOCK_ASSERT(td, MA_NOTOWNED); return (SIGPENDING(td) ? issignal(td) : 0); } /* * Arrange for ast() to handle unmasked pending signals on return to user * mode. This must be called whenever a signal is added to td_sigqueue or * unmasked in td_sigmask. */ void signotify(struct thread *td) { struct proc *p; p = td->td_proc; PROC_LOCK_ASSERT(p, MA_OWNED); if (SIGPENDING(td)) { thread_lock(td); td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING; thread_unlock(td); } } int sigonstack(size_t sp) { struct thread *td = curthread; return ((td->td_pflags & TDP_ALTSTACK) ? #if defined(COMPAT_43) ((td->td_sigstk.ss_size == 0) ? (td->td_sigstk.ss_flags & SS_ONSTACK) : ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)) #else ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size) #endif : 0); } static __inline int sigprop(int sig) { if (sig > 0 && sig < NSIG) return (sigproptbl[_SIG_IDX(sig)]); return (0); } int sig_ffs(sigset_t *set) { int i; for (i = 0; i < _SIG_WORDS; i++) if (set->__bits[i]) return (ffs(set->__bits[i]) + (i * 32)); return (0); } /* * kern_sigaction * sigaction * freebsd4_sigaction * osigaction */ int kern_sigaction(td, sig, act, oact, flags) struct thread *td; register int sig; struct sigaction *act, *oact; int flags; { struct sigacts *ps; struct proc *p = td->td_proc; if (!_SIG_VALID(sig)) return (EINVAL); PROC_LOCK(p); ps = p->p_sigacts; mtx_lock(&ps->ps_mtx); if (oact) { oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)]; oact->sa_flags = 0; if (SIGISMEMBER(ps->ps_sigonstack, sig)) oact->sa_flags |= SA_ONSTACK; if (!SIGISMEMBER(ps->ps_sigintr, sig)) oact->sa_flags |= SA_RESTART; if (SIGISMEMBER(ps->ps_sigreset, sig)) oact->sa_flags |= SA_RESETHAND; if (SIGISMEMBER(ps->ps_signodefer, sig)) oact->sa_flags |= SA_NODEFER; if (SIGISMEMBER(ps->ps_siginfo, sig)) { oact->sa_flags |= SA_SIGINFO; oact->sa_sigaction = (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)]; } else oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)]; if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP) oact->sa_flags |= SA_NOCLDSTOP; if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT) oact->sa_flags |= SA_NOCLDWAIT; } if (act) { if ((sig == SIGKILL || sig == SIGSTOP) && act->sa_handler != SIG_DFL) { mtx_unlock(&ps->ps_mtx); PROC_UNLOCK(p); return (EINVAL); } /* * Change setting atomically. */ ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask; SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]); if (act->sa_flags & SA_SIGINFO) { ps->ps_sigact[_SIG_IDX(sig)] = (__sighandler_t *)act->sa_sigaction; SIGADDSET(ps->ps_siginfo, sig); } else { ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler; SIGDELSET(ps->ps_siginfo, sig); } if (!(act->sa_flags & SA_RESTART)) SIGADDSET(ps->ps_sigintr, sig); else SIGDELSET(ps->ps_sigintr, sig); if (act->sa_flags & SA_ONSTACK) SIGADDSET(ps->ps_sigonstack, sig); else SIGDELSET(ps->ps_sigonstack, sig); if (act->sa_flags & SA_RESETHAND) SIGADDSET(ps->ps_sigreset, sig); else SIGDELSET(ps->ps_sigreset, sig); if (act->sa_flags & SA_NODEFER) SIGADDSET(ps->ps_signodefer, sig); else SIGDELSET(ps->ps_signodefer, sig); if (sig == SIGCHLD) { if (act->sa_flags & SA_NOCLDSTOP) ps->ps_flag |= PS_NOCLDSTOP; else ps->ps_flag &= ~PS_NOCLDSTOP; if (act->sa_flags & SA_NOCLDWAIT) { /* * Paranoia: since SA_NOCLDWAIT is implemented * by reparenting the dying child to PID 1 (and * trust it to reap the zombie), PID 1 itself * is forbidden to set SA_NOCLDWAIT. */ if (p->p_pid == 1) ps->ps_flag &= ~PS_NOCLDWAIT; else ps->ps_flag |= PS_NOCLDWAIT; } else ps->ps_flag &= ~PS_NOCLDWAIT; if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) ps->ps_flag |= PS_CLDSIGIGN; else ps->ps_flag &= ~PS_CLDSIGIGN; } /* * Set bit in ps_sigignore for signals that are set to SIG_IGN, * and for signals set to SIG_DFL where the default is to * ignore. However, don't put SIGCONT in ps_sigignore, as we * have to restart the process. */ if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || (sigprop(sig) & SA_IGNORE && ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) { /* never to be seen again */ sigqueue_delete_proc(p, sig); if (sig != SIGCONT) /* easier in psignal */ SIGADDSET(ps->ps_sigignore, sig); SIGDELSET(ps->ps_sigcatch, sig); } else { SIGDELSET(ps->ps_sigignore, sig); if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL) SIGDELSET(ps->ps_sigcatch, sig); else SIGADDSET(ps->ps_sigcatch, sig); } #ifdef COMPAT_FREEBSD4 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || (flags & KSA_FREEBSD4) == 0) SIGDELSET(ps->ps_freebsd4, sig); else SIGADDSET(ps->ps_freebsd4, sig); #endif #ifdef COMPAT_43 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || (flags & KSA_OSIGSET) == 0) SIGDELSET(ps->ps_osigset, sig); else SIGADDSET(ps->ps_osigset, sig); #endif } mtx_unlock(&ps->ps_mtx); PROC_UNLOCK(p); return (0); } #ifndef _SYS_SYSPROTO_H_ struct sigaction_args { int sig; struct sigaction *act; struct sigaction *oact; }; #endif int sys_sigaction(td, uap) struct thread *td; register struct sigaction_args *uap; { struct sigaction act, oact; register struct sigaction *actp, *oactp; int error; actp = (uap->act != NULL) ? &act : NULL; oactp = (uap->oact != NULL) ? &oact : NULL; if (actp) { error = copyin(uap->act, actp, sizeof(act)); if (error) return (error); } error = kern_sigaction(td, uap->sig, actp, oactp, 0); if (oactp && !error) error = copyout(oactp, uap->oact, sizeof(oact)); return (error); } #ifdef COMPAT_FREEBSD4 #ifndef _SYS_SYSPROTO_H_ struct freebsd4_sigaction_args { int sig; struct sigaction *act; struct sigaction *oact; }; #endif int freebsd4_sigaction(td, uap) struct thread *td; register struct freebsd4_sigaction_args *uap; { struct sigaction act, oact; register struct sigaction *actp, *oactp; int error; actp = (uap->act != NULL) ? &act : NULL; oactp = (uap->oact != NULL) ? &oact : NULL; if (actp) { error = copyin(uap->act, actp, sizeof(act)); if (error) return (error); } error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4); if (oactp && !error) error = copyout(oactp, uap->oact, sizeof(oact)); return (error); } #endif /* COMAPT_FREEBSD4 */ #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ #ifndef _SYS_SYSPROTO_H_ struct osigaction_args { int signum; struct osigaction *nsa; struct osigaction *osa; }; #endif int osigaction(td, uap) struct thread *td; register struct osigaction_args *uap; { struct osigaction sa; struct sigaction nsa, osa; register struct sigaction *nsap, *osap; int error; if (uap->signum <= 0 || uap->signum >= ONSIG) return (EINVAL); nsap = (uap->nsa != NULL) ? &nsa : NULL; osap = (uap->osa != NULL) ? &osa : NULL; if (nsap) { error = copyin(uap->nsa, &sa, sizeof(sa)); if (error) return (error); nsap->sa_handler = sa.sa_handler; nsap->sa_flags = sa.sa_flags; OSIG2SIG(sa.sa_mask, nsap->sa_mask); } error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET); if (osap && !error) { sa.sa_handler = osap->sa_handler; sa.sa_flags = osap->sa_flags; SIG2OSIG(osap->sa_mask, sa.sa_mask); error = copyout(&sa, uap->osa, sizeof(sa)); } return (error); } #if !defined(__i386__) /* Avoid replicating the same stub everywhere */ int osigreturn(td, uap) struct thread *td; struct osigreturn_args *uap; { return (nosys(td, (struct nosys_args *)uap)); } #endif #endif /* COMPAT_43 */ /* * Initialize signal state for process 0; * set to ignore signals that are ignored by default. */ void siginit(p) struct proc *p; { register int i; struct sigacts *ps; PROC_LOCK(p); ps = p->p_sigacts; mtx_lock(&ps->ps_mtx); for (i = 1; i <= NSIG; i++) if (sigprop(i) & SA_IGNORE && i != SIGCONT) SIGADDSET(ps->ps_sigignore, i); mtx_unlock(&ps->ps_mtx); PROC_UNLOCK(p); } /* * Reset signals for an exec of the specified process. */ void execsigs(struct proc *p) { struct sigacts *ps; int sig; struct thread *td; /* * Reset caught signals. Held signals remain held * through td_sigmask (unless they were caught, * and are now ignored by default). */ PROC_LOCK_ASSERT(p, MA_OWNED); td = FIRST_THREAD_IN_PROC(p); ps = p->p_sigacts; mtx_lock(&ps->ps_mtx); while (SIGNOTEMPTY(ps->ps_sigcatch)) { sig = sig_ffs(&ps->ps_sigcatch); SIGDELSET(ps->ps_sigcatch, sig); if (sigprop(sig) & SA_IGNORE) { if (sig != SIGCONT) SIGADDSET(ps->ps_sigignore, sig); sigqueue_delete_proc(p, sig); } ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; } /* * Reset stack state to the user stack. * Clear set of signals caught on the signal stack. */ td->td_sigstk.ss_flags = SS_DISABLE; td->td_sigstk.ss_size = 0; td->td_sigstk.ss_sp = 0; td->td_pflags &= ~TDP_ALTSTACK; /* * Reset no zombies if child dies flag as Solaris does. */ ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN); if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL; mtx_unlock(&ps->ps_mtx); } /* * kern_sigprocmask() * * Manipulate signal mask. */ int kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset, int flags) { sigset_t new_block, oset1; struct proc *p; int error; p = td->td_proc; if (!(flags & SIGPROCMASK_PROC_LOCKED)) PROC_LOCK(p); if (oset != NULL) *oset = td->td_sigmask; error = 0; if (set != NULL) { switch (how) { case SIG_BLOCK: SIG_CANTMASK(*set); oset1 = td->td_sigmask; SIGSETOR(td->td_sigmask, *set); new_block = td->td_sigmask; SIGSETNAND(new_block, oset1); break; case SIG_UNBLOCK: SIGSETNAND(td->td_sigmask, *set); signotify(td); goto out; case SIG_SETMASK: SIG_CANTMASK(*set); oset1 = td->td_sigmask; if (flags & SIGPROCMASK_OLD) SIGSETLO(td->td_sigmask, *set); else td->td_sigmask = *set; new_block = td->td_sigmask; SIGSETNAND(new_block, oset1); signotify(td); break; default: error = EINVAL; goto out; } /* * The new_block set contains signals that were not previously * blocked, but are blocked now. * * In case we block any signal that was not previously blocked * for td, and process has the signal pending, try to schedule * signal delivery to some thread that does not block the * signal, possibly waking it up. */ if (p->p_numthreads != 1) reschedule_signals(p, new_block, flags); } out: if (!(flags & SIGPROCMASK_PROC_LOCKED)) PROC_UNLOCK(p); return (error); } #ifndef _SYS_SYSPROTO_H_ struct sigprocmask_args { int how; const sigset_t *set; sigset_t *oset; }; #endif int sys_sigprocmask(td, uap) register struct thread *td; struct sigprocmask_args *uap; { sigset_t set, oset; sigset_t *setp, *osetp; int error; setp = (uap->set != NULL) ? &set : NULL; osetp = (uap->oset != NULL) ? &oset : NULL; if (setp) { error = copyin(uap->set, setp, sizeof(set)); if (error) return (error); } error = kern_sigprocmask(td, uap->how, setp, osetp, 0); if (osetp && !error) { error = copyout(osetp, uap->oset, sizeof(oset)); } return (error); } #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ #ifndef _SYS_SYSPROTO_H_ struct osigprocmask_args { int how; osigset_t mask; }; #endif int osigprocmask(td, uap) register struct thread *td; struct osigprocmask_args *uap; { sigset_t set, oset; int error; OSIG2SIG(uap->mask, set); error = kern_sigprocmask(td, uap->how, &set, &oset, 1); SIG2OSIG(oset, td->td_retval[0]); return (error); } #endif /* COMPAT_43 */ int sys_sigwait(struct thread *td, struct sigwait_args *uap) { ksiginfo_t ksi; sigset_t set; int error; error = copyin(uap->set, &set, sizeof(set)); if (error) { td->td_retval[0] = error; return (0); } error = kern_sigtimedwait(td, set, &ksi, NULL); if (error) { if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT) error = ERESTART; if (error == ERESTART) return (error); td->td_retval[0] = error; return (0); } error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo)); td->td_retval[0] = error; return (0); } int sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap) { struct timespec ts; struct timespec *timeout; sigset_t set; ksiginfo_t ksi; int error; if (uap->timeout) { error = copyin(uap->timeout, &ts, sizeof(ts)); if (error) return (error); timeout = &ts; } else timeout = NULL; error = copyin(uap->set, &set, sizeof(set)); if (error) return (error); error = kern_sigtimedwait(td, set, &ksi, timeout); if (error) return (error); if (uap->info) error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t)); if (error == 0) td->td_retval[0] = ksi.ksi_signo; return (error); } int sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap) { ksiginfo_t ksi; sigset_t set; int error; error = copyin(uap->set, &set, sizeof(set)); if (error) return (error); error = kern_sigtimedwait(td, set, &ksi, NULL); if (error) return (error); if (uap->info) error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t)); if (error == 0) td->td_retval[0] = ksi.ksi_signo; return (error); } int kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi, struct timespec *timeout) { struct sigacts *ps; sigset_t saved_mask, new_block; struct proc *p; int error, sig, timo, timevalid = 0; struct timespec rts, ets, ts; struct timeval tv; p = td->td_proc; error = 0; ets.tv_sec = 0; ets.tv_nsec = 0; if (timeout != NULL) { if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) { timevalid = 1; getnanouptime(&rts); ets = rts; timespecadd(&ets, timeout); } } ksiginfo_init(ksi); /* Some signals can not be waited for. */ SIG_CANTMASK(waitset); ps = p->p_sigacts; PROC_LOCK(p); saved_mask = td->td_sigmask; SIGSETNAND(td->td_sigmask, waitset); for (;;) { mtx_lock(&ps->ps_mtx); sig = cursig(td); mtx_unlock(&ps->ps_mtx); if (sig != 0 && SIGISMEMBER(waitset, sig)) { if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 || sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) { error = 0; break; } } if (error != 0) break; /* * POSIX says this must be checked after looking for pending * signals. */ if (timeout != NULL) { if (!timevalid) { error = EINVAL; break; } getnanouptime(&rts); if (timespeccmp(&rts, &ets, >=)) { error = EAGAIN; break; } ts = ets; timespecsub(&ts, &rts); TIMESPEC_TO_TIMEVAL(&tv, &ts); timo = tvtohz(&tv); } else { timo = 0; } error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo); if (timeout != NULL) { if (error == ERESTART) { /* Timeout can not be restarted. */ error = EINTR; } else if (error == EAGAIN) { /* We will calculate timeout by ourself. */ error = 0; } } } new_block = saved_mask; SIGSETNAND(new_block, td->td_sigmask); td->td_sigmask = saved_mask; /* * Fewer signals can be delivered to us, reschedule signal * notification. */ if (p->p_numthreads != 1) reschedule_signals(p, new_block, 0); if (error == 0) { SDT_PROBE(proc, kernel, , signal__clear, sig, ksi, 0, 0, 0); if (ksi->ksi_code == SI_TIMER) itimer_accept(p, ksi->ksi_timerid, ksi); #ifdef KTRACE if (KTRPOINT(td, KTR_PSIG)) { sig_t action; mtx_lock(&ps->ps_mtx); action = ps->ps_sigact[_SIG_IDX(sig)]; mtx_unlock(&ps->ps_mtx); ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code); } #endif if (sig == SIGKILL) sigexit(td, sig); } PROC_UNLOCK(p); return (error); } #ifndef _SYS_SYSPROTO_H_ struct sigpending_args { sigset_t *set; }; #endif int sys_sigpending(td, uap) struct thread *td; struct sigpending_args *uap; { struct proc *p = td->td_proc; sigset_t pending; PROC_LOCK(p); pending = p->p_sigqueue.sq_signals; SIGSETOR(pending, td->td_sigqueue.sq_signals); PROC_UNLOCK(p); return (copyout(&pending, uap->set, sizeof(sigset_t))); } #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ #ifndef _SYS_SYSPROTO_H_ struct osigpending_args { int dummy; }; #endif int osigpending(td, uap) struct thread *td; struct osigpending_args *uap; { struct proc *p = td->td_proc; sigset_t pending; PROC_LOCK(p); pending = p->p_sigqueue.sq_signals; SIGSETOR(pending, td->td_sigqueue.sq_signals); PROC_UNLOCK(p); SIG2OSIG(pending, td->td_retval[0]); return (0); } #endif /* COMPAT_43 */ #if defined(COMPAT_43) /* * Generalized interface signal handler, 4.3-compatible. */ #ifndef _SYS_SYSPROTO_H_ struct osigvec_args { int signum; struct sigvec *nsv; struct sigvec *osv; }; #endif /* ARGSUSED */ int osigvec(td, uap) struct thread *td; register struct osigvec_args *uap; { struct sigvec vec; struct sigaction nsa, osa; register struct sigaction *nsap, *osap; int error; if (uap->signum <= 0 || uap->signum >= ONSIG) return (EINVAL); nsap = (uap->nsv != NULL) ? &nsa : NULL; osap = (uap->osv != NULL) ? &osa : NULL; if (nsap) { error = copyin(uap->nsv, &vec, sizeof(vec)); if (error) return (error); nsap->sa_handler = vec.sv_handler; OSIG2SIG(vec.sv_mask, nsap->sa_mask); nsap->sa_flags = vec.sv_flags; nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */ } error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET); if (osap && !error) { vec.sv_handler = osap->sa_handler; SIG2OSIG(osap->sa_mask, vec.sv_mask); vec.sv_flags = osap->sa_flags; vec.sv_flags &= ~SA_NOCLDWAIT; vec.sv_flags ^= SA_RESTART; error = copyout(&vec, uap->osv, sizeof(vec)); } return (error); } #ifndef _SYS_SYSPROTO_H_ struct osigblock_args { int mask; }; #endif int osigblock(td, uap) register struct thread *td; struct osigblock_args *uap; { sigset_t set, oset; OSIG2SIG(uap->mask, set); kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0); SIG2OSIG(oset, td->td_retval[0]); return (0); } #ifndef _SYS_SYSPROTO_H_ struct osigsetmask_args { int mask; }; #endif int osigsetmask(td, uap) struct thread *td; struct osigsetmask_args *uap; { sigset_t set, oset; OSIG2SIG(uap->mask, set); kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0); SIG2OSIG(oset, td->td_retval[0]); return (0); } #endif /* COMPAT_43 */ /* * Suspend calling thread until signal, providing mask to be set in the * meantime. */ #ifndef _SYS_SYSPROTO_H_ struct sigsuspend_args { const sigset_t *sigmask; }; #endif /* ARGSUSED */ int sys_sigsuspend(td, uap) struct thread *td; struct sigsuspend_args *uap; { sigset_t mask; int error; error = copyin(uap->sigmask, &mask, sizeof(mask)); if (error) return (error); return (kern_sigsuspend(td, mask)); } int kern_sigsuspend(struct thread *td, sigset_t mask) { struct proc *p = td->td_proc; int has_sig, sig; /* * When returning from sigsuspend, we want * the old mask to be restored after the * signal handler has finished. Thus, we * save it here and mark the sigacts structure * to indicate this. */ PROC_LOCK(p); kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask, SIGPROCMASK_PROC_LOCKED); td->td_pflags |= TDP_OLDMASK; /* * Process signals now. Otherwise, we can get spurious wakeup * due to signal entered process queue, but delivered to other * thread. But sigsuspend should return only on signal * delivery. */ (p->p_sysent->sv_set_syscall_retval)(td, EINTR); for (has_sig = 0; !has_sig;) { while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause", 0) == 0) /* void */; thread_suspend_check(0); mtx_lock(&p->p_sigacts->ps_mtx); while ((sig = cursig(td)) != 0) has_sig += postsig(sig); mtx_unlock(&p->p_sigacts->ps_mtx); } PROC_UNLOCK(p); td->td_errno = EINTR; td->td_pflags |= TDP_NERRNO; return (EJUSTRETURN); } #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ /* * Compatibility sigsuspend call for old binaries. Note nonstandard calling * convention: libc stub passes mask, not pointer, to save a copyin. */ #ifndef _SYS_SYSPROTO_H_ struct osigsuspend_args { osigset_t mask; }; #endif /* ARGSUSED */ int osigsuspend(td, uap) struct thread *td; struct osigsuspend_args *uap; { sigset_t mask; OSIG2SIG(uap->mask, mask); return (kern_sigsuspend(td, mask)); } #endif /* COMPAT_43 */ #if defined(COMPAT_43) #ifndef _SYS_SYSPROTO_H_ struct osigstack_args { struct sigstack *nss; struct sigstack *oss; }; #endif /* ARGSUSED */ int osigstack(td, uap) struct thread *td; register struct osigstack_args *uap; { struct sigstack nss, oss; int error = 0; if (uap->nss != NULL) { error = copyin(uap->nss, &nss, sizeof(nss)); if (error) return (error); } oss.ss_sp = td->td_sigstk.ss_sp; oss.ss_onstack = sigonstack(cpu_getstack(td)); if (uap->nss != NULL) { td->td_sigstk.ss_sp = nss.ss_sp; td->td_sigstk.ss_size = 0; td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK; td->td_pflags |= TDP_ALTSTACK; } if (uap->oss != NULL) error = copyout(&oss, uap->oss, sizeof(oss)); return (error); } #endif /* COMPAT_43 */ #ifndef _SYS_SYSPROTO_H_ struct sigaltstack_args { stack_t *ss; stack_t *oss; }; #endif /* ARGSUSED */ int sys_sigaltstack(td, uap) struct thread *td; register struct sigaltstack_args *uap; { stack_t ss, oss; int error; if (uap->ss != NULL) { error = copyin(uap->ss, &ss, sizeof(ss)); if (error) return (error); } error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL, (uap->oss != NULL) ? &oss : NULL); if (error) return (error); if (uap->oss != NULL) error = copyout(&oss, uap->oss, sizeof(stack_t)); return (error); } int kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss) { struct proc *p = td->td_proc; int oonstack; oonstack = sigonstack(cpu_getstack(td)); if (oss != NULL) { *oss = td->td_sigstk; oss->ss_flags = (td->td_pflags & TDP_ALTSTACK) ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE; } if (ss != NULL) { if (oonstack) return (EPERM); if ((ss->ss_flags & ~SS_DISABLE) != 0) return (EINVAL); if (!(ss->ss_flags & SS_DISABLE)) { if (ss->ss_size < p->p_sysent->sv_minsigstksz) return (ENOMEM); td->td_sigstk = *ss; td->td_pflags |= TDP_ALTSTACK; } else { td->td_pflags &= ~TDP_ALTSTACK; } } return (0); } /* * Common code for kill process group/broadcast kill. * cp is calling process. */ static int killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi) { struct proc *p; struct pgrp *pgrp; int err; int ret; ret = ESRCH; if (all) { /* * broadcast */ sx_slock(&allproc_lock); FOREACH_PROC_IN_SYSTEM(p) { PROC_LOCK(p); if (p->p_pid <= 1 || p->p_flag & P_SYSTEM || p == td->td_proc || p->p_state == PRS_NEW) { PROC_UNLOCK(p); continue; } err = p_cansignal(td, p, sig); if (err == 0) { if (sig) pksignal(p, sig, ksi); ret = err; } else if (ret == ESRCH) ret = err; PROC_UNLOCK(p); } sx_sunlock(&allproc_lock); } else { sx_slock(&proctree_lock); if (pgid == 0) { /* * zero pgid means send to my process group. */ pgrp = td->td_proc->p_pgrp; PGRP_LOCK(pgrp); } else { pgrp = pgfind(pgid); if (pgrp == NULL) { sx_sunlock(&proctree_lock); return (ESRCH); } } sx_sunlock(&proctree_lock); LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { PROC_LOCK(p); if (p->p_pid <= 1 || p->p_flag & P_SYSTEM || p->p_state == PRS_NEW) { PROC_UNLOCK(p); continue; } err = p_cansignal(td, p, sig); if (err == 0) { if (sig) pksignal(p, sig, ksi); ret = err; } else if (ret == ESRCH) ret = err; PROC_UNLOCK(p); } PGRP_UNLOCK(pgrp); } return (ret); } #ifndef _SYS_SYSPROTO_H_ struct kill_args { int pid; int signum; }; #endif /* ARGSUSED */ int sys_kill(struct thread *td, struct kill_args *uap) { ksiginfo_t ksi; struct proc *p; int error; /* * A process in capability mode can send signals only to himself. * The main rationale behind this is that abort(3) is implemented as * kill(getpid(), SIGABRT). */ if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid) return (ECAPMODE); AUDIT_ARG_SIGNUM(uap->signum); AUDIT_ARG_PID(uap->pid); if ((u_int)uap->signum > _SIG_MAXSIG) return (EINVAL); ksiginfo_init(&ksi); ksi.ksi_signo = uap->signum; ksi.ksi_code = SI_USER; ksi.ksi_pid = td->td_proc->p_pid; ksi.ksi_uid = td->td_ucred->cr_ruid; if (uap->pid > 0) { /* kill single process */ if ((p = pfind(uap->pid)) == NULL) { if ((p = zpfind(uap->pid)) == NULL) return (ESRCH); } AUDIT_ARG_PROCESS(p); error = p_cansignal(td, p, uap->signum); if (error == 0 && uap->signum) pksignal(p, uap->signum, &ksi); PROC_UNLOCK(p); return (error); } switch (uap->pid) { case -1: /* broadcast signal */ return (killpg1(td, uap->signum, 0, 1, &ksi)); case 0: /* signal own process group */ return (killpg1(td, uap->signum, 0, 0, &ksi)); default: /* negative explicit process group */ return (killpg1(td, uap->signum, -uap->pid, 0, &ksi)); } /* NOTREACHED */ } int sys_pdkill(td, uap) struct thread *td; struct pdkill_args *uap; { #ifdef PROCDESC struct proc *p; cap_rights_t rights; int error; AUDIT_ARG_SIGNUM(uap->signum); AUDIT_ARG_FD(uap->fd); if ((u_int)uap->signum > _SIG_MAXSIG) return (EINVAL); error = procdesc_find(td, uap->fd, cap_rights_init(&rights, CAP_PDKILL), &p); if (error) return (error); AUDIT_ARG_PROCESS(p); error = p_cansignal(td, p, uap->signum); if (error == 0 && uap->signum) kern_psignal(p, uap->signum); PROC_UNLOCK(p); return (error); #else return (ENOSYS); #endif } #if defined(COMPAT_43) #ifndef _SYS_SYSPROTO_H_ struct okillpg_args { int pgid; int signum; }; #endif /* ARGSUSED */ int okillpg(struct thread *td, struct okillpg_args *uap) { ksiginfo_t ksi; AUDIT_ARG_SIGNUM(uap->signum); AUDIT_ARG_PID(uap->pgid); if ((u_int)uap->signum > _SIG_MAXSIG) return (EINVAL); ksiginfo_init(&ksi); ksi.ksi_signo = uap->signum; ksi.ksi_code = SI_USER; ksi.ksi_pid = td->td_proc->p_pid; ksi.ksi_uid = td->td_ucred->cr_ruid; return (killpg1(td, uap->signum, uap->pgid, 0, &ksi)); } #endif /* COMPAT_43 */ #ifndef _SYS_SYSPROTO_H_ struct sigqueue_args { pid_t pid; int signum; /* union sigval */ void *value; }; #endif int sys_sigqueue(struct thread *td, struct sigqueue_args *uap) { ksiginfo_t ksi; struct proc *p; int error; if ((u_int)uap->signum > _SIG_MAXSIG) return (EINVAL); /* * Specification says sigqueue can only send signal to * single process. */ if (uap->pid <= 0) return (EINVAL); if ((p = pfind(uap->pid)) == NULL) { if ((p = zpfind(uap->pid)) == NULL) return (ESRCH); } error = p_cansignal(td, p, uap->signum); if (error == 0 && uap->signum != 0) { ksiginfo_init(&ksi); ksi.ksi_flags = KSI_SIGQ; ksi.ksi_signo = uap->signum; ksi.ksi_code = SI_QUEUE; ksi.ksi_pid = td->td_proc->p_pid; ksi.ksi_uid = td->td_ucred->cr_ruid; ksi.ksi_value.sival_ptr = uap->value; error = pksignal(p, ksi.ksi_signo, &ksi); } PROC_UNLOCK(p); return (error); } /* * Send a signal to a process group. */ void gsignal(int pgid, int sig, ksiginfo_t *ksi) { struct pgrp *pgrp; if (pgid != 0) { sx_slock(&proctree_lock); pgrp = pgfind(pgid); sx_sunlock(&proctree_lock); if (pgrp != NULL) { pgsignal(pgrp, sig, 0, ksi); PGRP_UNLOCK(pgrp); } } } /* * Send a signal to a process group. If checktty is 1, * limit to members which have a controlling terminal. */ void pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi) { struct proc *p; if (pgrp) { PGRP_LOCK_ASSERT(pgrp, MA_OWNED); LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { PROC_LOCK(p); if (p->p_state == PRS_NORMAL && (checkctty == 0 || p->p_flag & P_CONTROLT)) pksignal(p, sig, ksi); PROC_UNLOCK(p); } } } /* * Send a signal caused by a trap to the current thread. If it will be * caught immediately, deliver it with correct code. Otherwise, post it * normally. */ void trapsignal(struct thread *td, ksiginfo_t *ksi) { struct sigacts *ps; sigset_t mask; struct proc *p; int sig; int code; p = td->td_proc; sig = ksi->ksi_signo; code = ksi->ksi_code; KASSERT(_SIG_VALID(sig), ("invalid signal")); PROC_LOCK(p); ps = p->p_sigacts; mtx_lock(&ps->ps_mtx); if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) && !SIGISMEMBER(td->td_sigmask, sig)) { td->td_ru.ru_nsignals++; #ifdef KTRACE if (KTRPOINT(curthread, KTR_PSIG)) ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)], &td->td_sigmask, code); #endif (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)], ksi, &td->td_sigmask); mask = ps->ps_catchmask[_SIG_IDX(sig)]; if (!SIGISMEMBER(ps->ps_signodefer, sig)) SIGADDSET(mask, sig); kern_sigprocmask(td, SIG_BLOCK, &mask, NULL, SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED); if (SIGISMEMBER(ps->ps_sigreset, sig)) { /* * See kern_sigaction() for origin of this code. */ SIGDELSET(ps->ps_sigcatch, sig); if (sig != SIGCONT && sigprop(sig) & SA_IGNORE) SIGADDSET(ps->ps_sigignore, sig); ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; } mtx_unlock(&ps->ps_mtx); } else { /* * Avoid a possible infinite loop if the thread * masking the signal or process is ignoring the * signal. */ if (kern_forcesigexit && (SIGISMEMBER(td->td_sigmask, sig) || ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) { SIGDELSET(td->td_sigmask, sig); SIGDELSET(ps->ps_sigcatch, sig); SIGDELSET(ps->ps_sigignore, sig); ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; } mtx_unlock(&ps->ps_mtx); p->p_code = code; /* XXX for core dump/debugger */ p->p_sig = sig; /* XXX to verify code */ tdsendsignal(p, td, sig, ksi); } PROC_UNLOCK(p); } static struct thread * sigtd(struct proc *p, int sig, int prop) { struct thread *td, *signal_td; PROC_LOCK_ASSERT(p, MA_OWNED); /* * Check if current thread can handle the signal without * switching context to another thread. */ if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig)) return (curthread); signal_td = NULL; FOREACH_THREAD_IN_PROC(p, td) { if (!SIGISMEMBER(td->td_sigmask, sig)) { signal_td = td; break; } } if (signal_td == NULL) signal_td = FIRST_THREAD_IN_PROC(p); return (signal_td); } /* * Send the signal to the process. If the signal has an action, the action * is usually performed by the target process rather than the caller; we add * the signal to the set of pending signals for the process. * * Exceptions: * o When a stop signal is sent to a sleeping process that takes the * default action, the process is stopped without awakening it. * o SIGCONT restarts stopped processes (or puts them back to sleep) * regardless of the signal action (eg, blocked or ignored). * * Other ignored signals are discarded immediately. * * NB: This function may be entered from the debugger via the "kill" DDB * command. There is little that can be done to mitigate the possibly messy * side effects of this unwise possibility. */ void kern_psignal(struct proc *p, int sig) { ksiginfo_t ksi; ksiginfo_init(&ksi); ksi.ksi_signo = sig; ksi.ksi_code = SI_KERNEL; (void) tdsendsignal(p, NULL, sig, &ksi); } int pksignal(struct proc *p, int sig, ksiginfo_t *ksi) { return (tdsendsignal(p, NULL, sig, ksi)); } /* Utility function for finding a thread to send signal event to. */ int sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd) { struct thread *td; if (sigev->sigev_notify == SIGEV_THREAD_ID) { td = tdfind(sigev->sigev_notify_thread_id, p->p_pid); if (td == NULL) return (ESRCH); *ttd = td; } else { *ttd = NULL; PROC_LOCK(p); } return (0); } void tdsignal(struct thread *td, int sig) { ksiginfo_t ksi; ksiginfo_init(&ksi); ksi.ksi_signo = sig; ksi.ksi_code = SI_KERNEL; (void) tdsendsignal(td->td_proc, td, sig, &ksi); } void tdksignal(struct thread *td, int sig, ksiginfo_t *ksi) { (void) tdsendsignal(td->td_proc, td, sig, ksi); } int tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi) { sig_t action; sigqueue_t *sigqueue; int prop; struct sigacts *ps; int intrval; int ret = 0; int wakeup_swapper; MPASS(td == NULL || p == td->td_proc); PROC_LOCK_ASSERT(p, MA_OWNED); if (!_SIG_VALID(sig)) panic("%s(): invalid signal %d", __func__, sig); KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__)); /* * IEEE Std 1003.1-2001: return success when killing a zombie. */ if (p->p_state == PRS_ZOMBIE) { if (ksi && (ksi->ksi_flags & KSI_INS)) ksiginfo_tryfree(ksi); return (ret); } ps = p->p_sigacts; KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig); prop = sigprop(sig); if (td == NULL) { td = sigtd(p, sig, prop); sigqueue = &p->p_sigqueue; } else sigqueue = &td->td_sigqueue; SDT_PROBE(proc, kernel, , signal__send, td, p, sig, 0, 0 ); /* * If the signal is being ignored, * then we forget about it immediately. * (Note: we don't set SIGCONT in ps_sigignore, * and if it is set to SIG_IGN, * action will be SIG_DFL here.) */ mtx_lock(&ps->ps_mtx); if (SIGISMEMBER(ps->ps_sigignore, sig)) { SDT_PROBE(proc, kernel, , signal__discard, td, p, sig, 0, 0 ); mtx_unlock(&ps->ps_mtx); if (ksi && (ksi->ksi_flags & KSI_INS)) ksiginfo_tryfree(ksi); return (ret); } if (SIGISMEMBER(td->td_sigmask, sig)) action = SIG_HOLD; else if (SIGISMEMBER(ps->ps_sigcatch, sig)) action = SIG_CATCH; else action = SIG_DFL; if (SIGISMEMBER(ps->ps_sigintr, sig)) intrval = EINTR; else intrval = ERESTART; mtx_unlock(&ps->ps_mtx); if (prop & SA_CONT) sigqueue_delete_stopmask_proc(p); else if (prop & SA_STOP) { /* * If sending a tty stop signal to a member of an orphaned * process group, discard the signal here if the action * is default; don't stop the process below if sleeping, * and don't clear any pending SIGCONT. */ if ((prop & SA_TTYSTOP) && (p->p_pgrp->pg_jobc == 0) && (action == SIG_DFL)) { if (ksi && (ksi->ksi_flags & KSI_INS)) ksiginfo_tryfree(ksi); return (ret); } sigqueue_delete_proc(p, SIGCONT); if (p->p_flag & P_CONTINUED) { p->p_flag &= ~P_CONTINUED; PROC_LOCK(p->p_pptr); sigqueue_take(p->p_ksi); PROC_UNLOCK(p->p_pptr); } } ret = sigqueue_add(sigqueue, sig, ksi); if (ret != 0) return (ret); signotify(td); /* * Defer further processing for signals which are held, * except that stopped processes must be continued by SIGCONT. */ if (action == SIG_HOLD && !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG))) return (ret); /* * SIGKILL: Remove procfs STOPEVENTs. */ if (sig == SIGKILL) { /* from procfs_ioctl.c: PIOCBIC */ p->p_stops = 0; /* from procfs_ioctl.c: PIOCCONT */ p->p_step = 0; wakeup(&p->p_step); } /* * Some signals have a process-wide effect and a per-thread * component. Most processing occurs when the process next * tries to cross the user boundary, however there are some * times when processing needs to be done immediately, such as * waking up threads so that they can cross the user boundary. * We try to do the per-process part here. */ if (P_SHOULDSTOP(p)) { KASSERT(!(p->p_flag & P_WEXIT), ("signal to stopped but exiting process")); if (sig == SIGKILL) { /* * If traced process is already stopped, * then no further action is necessary. */ if (p->p_flag & P_TRACED) goto out; /* * SIGKILL sets process running. * It will die elsewhere. * All threads must be restarted. */ p->p_flag &= ~P_STOPPED_SIG; goto runfast; } if (prop & SA_CONT) { /* * If traced process is already stopped, * then no further action is necessary. */ if (p->p_flag & P_TRACED) goto out; /* * If SIGCONT is default (or ignored), we continue the * process but don't leave the signal in sigqueue as * it has no further action. If SIGCONT is held, we * continue the process and leave the signal in * sigqueue. If the process catches SIGCONT, let it * handle the signal itself. If it isn't waiting on * an event, it goes back to run state. * Otherwise, process goes back to sleep state. */ p->p_flag &= ~P_STOPPED_SIG; PROC_SLOCK(p); if (p->p_numthreads == p->p_suspcount) { PROC_SUNLOCK(p); p->p_flag |= P_CONTINUED; p->p_xstat = SIGCONT; PROC_LOCK(p->p_pptr); childproc_continued(p); PROC_UNLOCK(p->p_pptr); PROC_SLOCK(p); } if (action == SIG_DFL) { thread_unsuspend(p); PROC_SUNLOCK(p); sigqueue_delete(sigqueue, sig); goto out; } if (action == SIG_CATCH) { /* * The process wants to catch it so it needs * to run at least one thread, but which one? */ PROC_SUNLOCK(p); goto runfast; } /* * The signal is not ignored or caught. */ thread_unsuspend(p); PROC_SUNLOCK(p); goto out; } if (prop & SA_STOP) { /* * If traced process is already stopped, * then no further action is necessary. */ if (p->p_flag & P_TRACED) goto out; /* * Already stopped, don't need to stop again * (If we did the shell could get confused). * Just make sure the signal STOP bit set. */ p->p_flag |= P_STOPPED_SIG; sigqueue_delete(sigqueue, sig); goto out; } /* * All other kinds of signals: * If a thread is sleeping interruptibly, simulate a * wakeup so that when it is continued it will be made * runnable and can look at the signal. However, don't make * the PROCESS runnable, leave it stopped. * It may run a bit until it hits a thread_suspend_check(). */ wakeup_swapper = 0; PROC_SLOCK(p); thread_lock(td); if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR)) wakeup_swapper = sleepq_abort(td, intrval); thread_unlock(td); PROC_SUNLOCK(p); if (wakeup_swapper) kick_proc0(); goto out; /* * Mutexes are short lived. Threads waiting on them will * hit thread_suspend_check() soon. */ } else if (p->p_state == PRS_NORMAL) { if (p->p_flag & P_TRACED || action == SIG_CATCH) { tdsigwakeup(td, sig, action, intrval); goto out; } MPASS(action == SIG_DFL); if (prop & SA_STOP) { if (p->p_flag & (P_PPWAIT|P_WEXIT)) goto out; p->p_flag |= P_STOPPED_SIG; p->p_xstat = sig; PROC_SLOCK(p); sig_suspend_threads(td, p, 1); if (p->p_numthreads == p->p_suspcount) { /* * only thread sending signal to another * process can reach here, if thread is sending * signal to its process, because thread does * not suspend itself here, p_numthreads * should never be equal to p_suspcount. */ thread_stopped(p); PROC_SUNLOCK(p); sigqueue_delete_proc(p, p->p_xstat); } else PROC_SUNLOCK(p); goto out; } } else { /* Not in "NORMAL" state. discard the signal. */ sigqueue_delete(sigqueue, sig); goto out; } /* * The process is not stopped so we need to apply the signal to all the * running threads. */ runfast: tdsigwakeup(td, sig, action, intrval); PROC_SLOCK(p); thread_unsuspend(p); PROC_SUNLOCK(p); out: /* If we jump here, proc slock should not be owned. */ PROC_SLOCK_ASSERT(p, MA_NOTOWNED); return (ret); } /* * The force of a signal has been directed against a single * thread. We need to see what we can do about knocking it * out of any sleep it may be in etc. */ static void tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval) { struct proc *p = td->td_proc; register int prop; int wakeup_swapper; wakeup_swapper = 0; PROC_LOCK_ASSERT(p, MA_OWNED); prop = sigprop(sig); PROC_SLOCK(p); thread_lock(td); /* * Bring the priority of a thread up if we want it to get * killed in this lifetime. */ if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER) sched_prio(td, PUSER); if (TD_ON_SLEEPQ(td)) { /* * If thread is sleeping uninterruptibly * we can't interrupt the sleep... the signal will * be noticed when the process returns through * trap() or syscall(). */ if ((td->td_flags & TDF_SINTR) == 0) goto out; /* * If SIGCONT is default (or ignored) and process is * asleep, we are finished; the process should not * be awakened. */ if ((prop & SA_CONT) && action == SIG_DFL) { thread_unlock(td); PROC_SUNLOCK(p); sigqueue_delete(&p->p_sigqueue, sig); /* * It may be on either list in this state. * Remove from both for now. */ sigqueue_delete(&td->td_sigqueue, sig); return; } /* * Don't awaken a sleeping thread for SIGSTOP if the * STOP signal is deferred. */ if ((prop & SA_STOP) && (td->td_flags & TDF_SBDRY)) goto out; /* * Give low priority threads a better chance to run. */ if (td->td_priority > PUSER) sched_prio(td, PUSER); wakeup_swapper = sleepq_abort(td, intrval); } else { /* * Other states do nothing with the signal immediately, * other than kicking ourselves if we are running. * It will either never be noticed, or noticed very soon. */ #ifdef SMP if (TD_IS_RUNNING(td) && td != curthread) forward_signal(td); #endif } out: PROC_SUNLOCK(p); thread_unlock(td); if (wakeup_swapper) kick_proc0(); } static void sig_suspend_threads(struct thread *td, struct proc *p, int sending) { struct thread *td2; PROC_LOCK_ASSERT(p, MA_OWNED); PROC_SLOCK_ASSERT(p, MA_OWNED); FOREACH_THREAD_IN_PROC(p, td2) { thread_lock(td2); td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK; if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) && (td2->td_flags & TDF_SINTR)) { if (td2->td_flags & TDF_SBDRY) { /* * Once a thread is asleep with * TDF_SBDRY set, it should never * become suspended due to this check. */ KASSERT(!TD_IS_SUSPENDED(td2), ("thread with deferred stops suspended")); } else if (!TD_IS_SUSPENDED(td2)) { thread_suspend_one(td2); } } else if (!TD_IS_SUSPENDED(td2)) { if (sending || td != td2) td2->td_flags |= TDF_ASTPENDING; #ifdef SMP if (TD_IS_RUNNING(td2) && td2 != td) forward_signal(td2); #endif } thread_unlock(td2); } } int ptracestop(struct thread *td, int sig) { struct proc *p = td->td_proc; 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; 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_XSIG; PROC_SUNLOCK(p); return (sig); } /* * Just make wait() to work, the last stopped thread * will win. */ p->p_xstat = sig; p->p_xthread = td; 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); 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) break; goto stopme; } } PROC_SUNLOCK(p); return (td->td_xsig); } static void reschedule_signals(struct proc *p, sigset_t block, int flags) { struct sigacts *ps; struct thread *td; int sig; PROC_LOCK_ASSERT(p, MA_OWNED); if (SIGISEMPTY(p->p_siglist)) return; ps = p->p_sigacts; SIGSETAND(block, p->p_siglist); while ((sig = sig_ffs(&block)) != 0) { SIGDELSET(block, sig); td = sigtd(p, sig, 0); signotify(td); if (!(flags & SIGPROCMASK_PS_LOCKED)) mtx_lock(&ps->ps_mtx); if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig)) tdsigwakeup(td, sig, SIG_CATCH, (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR : ERESTART)); if (!(flags & SIGPROCMASK_PS_LOCKED)) mtx_unlock(&ps->ps_mtx); } } void tdsigcleanup(struct thread *td) { struct proc *p; sigset_t unblocked; p = td->td_proc; PROC_LOCK_ASSERT(p, MA_OWNED); sigqueue_flush(&td->td_sigqueue); if (p->p_numthreads == 1) return; /* * Since we cannot handle signals, notify signal post code * about this by filling the sigmask. * * Also, if needed, wake up thread(s) that do not block the * same signals as the exiting thread, since the thread might * have been selected for delivery and woken up. */ SIGFILLSET(unblocked); SIGSETNAND(unblocked, td->td_sigmask); SIGFILLSET(td->td_sigmask); reschedule_signals(p, unblocked, 0); } /* * Defer the delivery of SIGSTOP for the current thread. Returns true * if stops were deferred and false if they were already deferred. */ int sigdeferstop(void) { struct thread *td; td = curthread; if (td->td_flags & TDF_SBDRY) return (0); thread_lock(td); td->td_flags |= TDF_SBDRY; thread_unlock(td); return (1); } /* * Permit the delivery of SIGSTOP for the current thread. This does * not immediately suspend if a stop was posted. Instead, the thread * will suspend either via ast() or a subsequent interruptible sleep. */ void sigallowstop() { struct thread *td; td = curthread; thread_lock(td); td->td_flags &= ~TDF_SBDRY; thread_unlock(td); } /* * If the current process has received a signal (should be caught or cause * termination, should interrupt current syscall), return the signal number. * Stop signals with default action are processed immediately, then cleared; * they aren't returned. This is checked after each entry to the system for * a syscall or trap (though this can usually be done without calling issignal * by checking the pending signal masks in cursig.) The normal call * sequence is * * while (sig = cursig(curthread)) * postsig(sig); */ static int issignal(struct thread *td) { struct proc *p; struct sigacts *ps; struct sigqueue *queue; sigset_t sigpending; int sig, prop, newsig; p = td->td_proc; ps = p->p_sigacts; mtx_assert(&ps->ps_mtx, MA_OWNED); PROC_LOCK_ASSERT(p, MA_OWNED); for (;;) { int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG); sigpending = td->td_sigqueue.sq_signals; SIGSETOR(sigpending, p->p_sigqueue.sq_signals); SIGSETNAND(sigpending, td->td_sigmask); if (p->p_flag & P_PPWAIT || td->td_flags & TDF_SBDRY) SIG_STOPSIGMASK(sigpending); if (SIGISEMPTY(sigpending)) /* no signal to send */ return (0); sig = sig_ffs(&sigpending); if (p->p_stops & S_SIG) { mtx_unlock(&ps->ps_mtx); stopevent(p, S_SIG, sig); mtx_lock(&ps->ps_mtx); } /* * We should see pending but ignored signals * only if P_TRACED was on when they were posted. */ if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) { sigqueue_delete(&td->td_sigqueue, sig); sigqueue_delete(&p->p_sigqueue, sig); continue; } if (p->p_flag & P_TRACED && (p->p_flag & P_PPTRACE) == 0) { /* * If traced, always stop. * Remove old signal from queue before the stop. * XXX shrug off debugger, it causes siginfo to * be thrown away. */ queue = &td->td_sigqueue; td->td_dbgksi.ksi_signo = 0; if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) { queue = &p->p_sigqueue; sigqueue_get(queue, sig, &td->td_dbgksi); } mtx_unlock(&ps->ps_mtx); newsig = ptracestop(td, sig); mtx_lock(&ps->ps_mtx); if (sig != newsig) { /* * If parent wants us to take the signal, * then it will leave it in p->p_xstat; * 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); } /* * 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) continue; } prop = sigprop(sig); /* * Decide whether the signal should be returned. * Return the signal's number, or fall through * to clear it from the pending mask. */ switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) { case (intptr_t)SIG_DFL: /* * Don't take default actions on system processes. */ if (p->p_pid <= 1) { #ifdef DIAGNOSTIC /* * Are you sure you want to ignore SIGSEGV * in init? XXX */ printf("Process (pid %lu) got signal %d\n", (u_long)p->p_pid, sig); #endif break; /* == ignore */ } /* * If there is a pending stop signal to process * with default action, stop here, * then clear the signal. However, * if process is member of an orphaned * process group, ignore tty stop signals. */ if (prop & SA_STOP) { if (p->p_flag & (P_TRACED|P_WEXIT) || (p->p_pgrp->pg_jobc == 0 && prop & SA_TTYSTOP)) break; /* == ignore */ mtx_unlock(&ps->ps_mtx); WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, &p->p_mtx.lock_object, "Catching SIGSTOP"); p->p_flag |= P_STOPPED_SIG; p->p_xstat = sig; PROC_SLOCK(p); sig_suspend_threads(td, p, 0); thread_suspend_switch(td); PROC_SUNLOCK(p); mtx_lock(&ps->ps_mtx); break; } else if (prop & SA_IGNORE) { /* * Except for SIGCONT, shouldn't get here. * Default action is to ignore; drop it. */ break; /* == ignore */ } else return (sig); /*NOTREACHED*/ case (intptr_t)SIG_IGN: /* * Masking above should prevent us ever trying * to take action on an ignored signal other * than SIGCONT, unless process is traced. */ if ((prop & SA_CONT) == 0 && (p->p_flag & P_TRACED) == 0) printf("issignal\n"); break; /* == ignore */ default: /* * This signal has an action, let * postsig() process it. */ return (sig); } sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */ sigqueue_delete(&p->p_sigqueue, sig); } /* NOTREACHED */ } void thread_stopped(struct proc *p) { int n; PROC_LOCK_ASSERT(p, MA_OWNED); PROC_SLOCK_ASSERT(p, MA_OWNED); n = p->p_suspcount; if (p == curproc) n++; if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) { PROC_SUNLOCK(p); p->p_flag &= ~P_WAITED; PROC_LOCK(p->p_pptr); childproc_stopped(p, (p->p_flag & P_TRACED) ? CLD_TRAPPED : CLD_STOPPED); PROC_UNLOCK(p->p_pptr); PROC_SLOCK(p); } } /* * Take the action for the specified signal * from the current set of pending signals. */ int postsig(sig) register int sig; { struct thread *td = curthread; register struct proc *p = td->td_proc; struct sigacts *ps; sig_t action; ksiginfo_t ksi; sigset_t returnmask, mask; KASSERT(sig != 0, ("postsig")); PROC_LOCK_ASSERT(p, MA_OWNED); ps = p->p_sigacts; mtx_assert(&ps->ps_mtx, MA_OWNED); ksiginfo_init(&ksi); if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 && sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0) return (0); ksi.ksi_signo = sig; if (ksi.ksi_code == SI_TIMER) itimer_accept(p, ksi.ksi_timerid, &ksi); action = ps->ps_sigact[_SIG_IDX(sig)]; #ifdef KTRACE if (KTRPOINT(td, KTR_PSIG)) ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ? &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code); #endif if (p->p_stops & S_SIG) { mtx_unlock(&ps->ps_mtx); stopevent(p, S_SIG, sig); mtx_lock(&ps->ps_mtx); } if (action == SIG_DFL) { /* * Default action, where the default is to kill * the process. (Other cases were ignored above.) */ mtx_unlock(&ps->ps_mtx); sigexit(td, sig); /* NOTREACHED */ } else { /* * If we get here, the signal must be caught. */ KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig), ("postsig action")); /* * Set the new mask value and also defer further * occurrences of this signal. * * Special case: user has done a sigsuspend. Here the * current mask is not of interest, but rather the * mask from before the sigsuspend is what we want * restored after the signal processing is completed. */ if (td->td_pflags & TDP_OLDMASK) { returnmask = td->td_oldsigmask; td->td_pflags &= ~TDP_OLDMASK; } else returnmask = td->td_sigmask; mask = ps->ps_catchmask[_SIG_IDX(sig)]; if (!SIGISMEMBER(ps->ps_signodefer, sig)) SIGADDSET(mask, sig); kern_sigprocmask(td, SIG_BLOCK, &mask, NULL, SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED); if (SIGISMEMBER(ps->ps_sigreset, sig)) { /* * See kern_sigaction() for origin of this code. */ SIGDELSET(ps->ps_sigcatch, sig); if (sig != SIGCONT && sigprop(sig) & SA_IGNORE) SIGADDSET(ps->ps_sigignore, sig); ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; } td->td_ru.ru_nsignals++; if (p->p_sig == sig) { p->p_code = 0; p->p_sig = 0; } (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask); } return (1); } /* * Kill the current process for stated reason. */ void killproc(p, why) struct proc *p; char *why; { PROC_LOCK_ASSERT(p, MA_OWNED); CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid, p->p_comm); log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why); p->p_flag |= P_WKILLED; kern_psignal(p, SIGKILL); } /* * Force the current process to exit with the specified signal, dumping core * if appropriate. We bypass the normal tests for masked and caught signals, * allowing unrecoverable failures to terminate the process without changing * signal state. Mark the accounting record with the signal termination. * If dumping core, save the signal number for the debugger. Calls exit and * does not return. */ void sigexit(td, sig) struct thread *td; int sig; { struct proc *p = td->td_proc; PROC_LOCK_ASSERT(p, MA_OWNED); p->p_acflag |= AXSIG; /* * We must be single-threading to generate a core dump. This * ensures that the registers in the core file are up-to-date. * Also, the ELF dump handler assumes that the thread list doesn't * change out from under it. * * XXX If another thread attempts to single-thread before us * (e.g. via fork()), we won't get a dump at all. */ if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) { p->p_sig = sig; /* * Log signals which would cause core dumps * (Log as LOG_INFO to appease those who don't want * these messages.) * XXX : Todo, as well as euid, write out ruid too * Note that coredump() drops proc lock. */ if (coredump(td) == 0) sig |= WCOREFLAG; if (kern_logsigexit) log(LOG_INFO, "pid %d (%s), uid %d: exited on signal %d%s\n", p->p_pid, p->p_comm, td->td_ucred ? td->td_ucred->cr_uid : -1, sig &~ WCOREFLAG, sig & WCOREFLAG ? " (core dumped)" : ""); } else PROC_UNLOCK(p); exit1(td, W_EXITCODE(0, sig)); /* NOTREACHED */ } /* * Send queued SIGCHLD to parent when child process's state * is changed. */ static void sigparent(struct proc *p, int reason, int status) { PROC_LOCK_ASSERT(p, MA_OWNED); PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED); if (p->p_ksi != NULL) { p->p_ksi->ksi_signo = SIGCHLD; p->p_ksi->ksi_code = reason; p->p_ksi->ksi_status = status; p->p_ksi->ksi_pid = p->p_pid; p->p_ksi->ksi_uid = p->p_ucred->cr_ruid; if (KSI_ONQ(p->p_ksi)) return; } pksignal(p->p_pptr, SIGCHLD, p->p_ksi); } static void childproc_jobstate(struct proc *p, int reason, int sig) { struct sigacts *ps; PROC_LOCK_ASSERT(p, MA_OWNED); PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED); /* * Wake up parent sleeping in kern_wait(), also send * SIGCHLD to parent, but SIGCHLD does not guarantee * that parent will awake, because parent may masked * the signal. */ p->p_pptr->p_flag |= P_STATCHILD; wakeup(p->p_pptr); ps = p->p_pptr->p_sigacts; mtx_lock(&ps->ps_mtx); if ((ps->ps_flag & PS_NOCLDSTOP) == 0) { mtx_unlock(&ps->ps_mtx); sigparent(p, reason, sig); } else mtx_unlock(&ps->ps_mtx); } void childproc_stopped(struct proc *p, int reason) { /* p_xstat is a plain signal number, not a full wait() status here. */ childproc_jobstate(p, reason, p->p_xstat); } void childproc_continued(struct proc *p) { childproc_jobstate(p, CLD_CONTINUED, SIGCONT); } void childproc_exited(struct proc *p) { int reason; int xstat = p->p_xstat; /* convert to int */ int status; if (WCOREDUMP(xstat)) reason = CLD_DUMPED, status = WTERMSIG(xstat); else if (WIFSIGNALED(xstat)) reason = CLD_KILLED, status = WTERMSIG(xstat); else reason = CLD_EXITED, status = WEXITSTATUS(xstat); /* * XXX avoid calling wakeup(p->p_pptr), the work is * done in exit1(). */ sigparent(p, reason, status); } /* * We only have 1 character for the core count in the format * string, so the range will be 0-9 */ #define MAX_NUM_CORES 10 static int num_cores = 5; static int sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS) { int error; int new_val; new_val = num_cores; error = sysctl_handle_int(oidp, &new_val, 0, req); if (error != 0 || req->newptr == NULL) return (error); if (new_val > MAX_NUM_CORES) new_val = MAX_NUM_CORES; if (new_val < 0) new_val = 0; num_cores = new_val; return (0); } SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW, 0, sizeof(int), sysctl_debug_num_cores_check, "I", ""); #if defined(COMPRESS_USER_CORES) int compress_user_cores = 1; SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW, &compress_user_cores, 0, "Compression of user corefiles"); int compress_user_cores_gzlevel = -1; /* default level */ SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW, &compress_user_cores_gzlevel, -1, "Corefile gzip compression level"); #define GZ_SUFFIX ".gz" #define GZ_SUFFIX_LEN 3 #endif static char corefilename[MAXPATHLEN] = {"%N.core"}; TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename)); SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename, sizeof(corefilename), "Process corefile name format string"); /* * corefile_open(comm, uid, pid, td, compress, vpp, namep) * Expand the name described in corefilename, using name, uid, and pid * and open/create core file. * corefilename is a printf-like string, with three format specifiers: * %N name of process ("name") * %P process id (pid) * %U user id (uid) * For example, "%N.core" is the default; they can be disabled completely * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P". * This is controlled by the sysctl variable kern.corefile (see above). */ static int corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td, int compress, struct vnode **vpp, char **namep) { struct nameidata nd; struct sbuf sb; const char *format; char *hostname, *name; int indexpos, i, error, cmode, flags, oflags; hostname = NULL; format = corefilename; name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO); indexpos = -1; (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN); for (i = 0; format[i] != '\0'; i++) { switch (format[i]) { case '%': /* Format character */ i++; switch (format[i]) { case '%': sbuf_putc(&sb, '%'); break; case 'H': /* hostname */ if (hostname == NULL) { hostname = malloc(MAXHOSTNAMELEN, M_TEMP, M_WAITOK); } getcredhostname(td->td_ucred, hostname, MAXHOSTNAMELEN); sbuf_printf(&sb, "%s", hostname); break; case 'I': /* autoincrementing index */ sbuf_printf(&sb, "0"); indexpos = sbuf_len(&sb) - 1; break; case 'N': /* process name */ sbuf_printf(&sb, "%s", comm); break; case 'P': /* process id */ sbuf_printf(&sb, "%u", pid); break; case 'U': /* user id */ sbuf_printf(&sb, "%u", uid); break; default: log(LOG_ERR, "Unknown format character %c in " "corename `%s'\n", format[i], format); break; } break; default: sbuf_putc(&sb, format[i]); break; } } free(hostname, M_TEMP); #ifdef COMPRESS_USER_CORES if (compress) sbuf_printf(&sb, GZ_SUFFIX); #endif if (sbuf_error(&sb) != 0) { log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too " "long\n", (long)pid, comm, (u_long)uid); sbuf_delete(&sb); free(name, M_TEMP); return (ENOMEM); } sbuf_finish(&sb); sbuf_delete(&sb); cmode = S_IRUSR | S_IWUSR; oflags = VN_OPEN_NOAUDIT | (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0); /* * If the core format has a %I in it, then we need to check * for existing corefiles before returning a name. * To do this we iterate over 0..num_cores to find a * non-existing core file name to use. */ if (indexpos != -1) { for (i = 0; i < num_cores; i++) { flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW; name[indexpos] = '0' + i; NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td); error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL); if (error) { if (error == EEXIST) continue; log(LOG_ERR, "pid %d (%s), uid (%u): Path `%s' failed " "on initial open test, error = %d\n", pid, comm, uid, name, error); } goto out; } } flags = O_CREAT | FWRITE | O_NOFOLLOW; NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td); error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL); out: if (error) { #ifdef AUDIT audit_proc_coredump(td, name, error); #endif free(name, M_TEMP); return (error); } NDFREE(&nd, NDF_ONLY_PNBUF); *vpp = nd.ni_vp; *namep = name; return (0); } /* * Dump a process' core. The main routine does some * policy checking, and creates the name of the coredump; * then it passes on a vnode and a size limit to the process-specific * coredump routine if there is one; if there _is not_ one, it returns * ENOSYS; otherwise it returns the error from the process-specific routine. */ static int coredump(struct thread *td) { struct proc *p = td->td_proc; struct ucred *cred = td->td_ucred; struct vnode *vp; struct flock lf; struct vattr vattr; int error, error1, locked; struct mount *mp; char *name; /* name of corefile */ off_t limit; int compress; #ifdef COMPRESS_USER_CORES compress = compress_user_cores; #else compress = 0; #endif PROC_LOCK_ASSERT(p, MA_OWNED); MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td); _STOPEVENT(p, S_CORE, 0); if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0)) { PROC_UNLOCK(p); return (EFAULT); } /* * Note that the bulk of limit checking is done after * the corefile is created. The exception is if the limit * for corefiles is 0, in which case we don't bother * creating the corefile at all. This layout means that * a corefile is truncated instead of not being created, * if it is larger than the limit. */ limit = (off_t)lim_cur(p, RLIMIT_CORE); if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) { PROC_UNLOCK(p); return (EFBIG); } PROC_UNLOCK(p); restart: error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td, compress, &vp, &name); if (error != 0) return (error); /* Don't dump to non-regular files or files with links. */ if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 || vattr.va_nlink != 1) { VOP_UNLOCK(vp, 0); error = EFAULT; goto close; } VOP_UNLOCK(vp, 0); lf.l_whence = SEEK_SET; lf.l_start = 0; lf.l_len = 0; lf.l_type = F_WRLCK; locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0); if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { lf.l_type = F_UNLCK; if (locked) VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); if ((error = vn_close(vp, FWRITE, cred, td)) != 0) goto out; if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0) goto out; free(name, M_TEMP); goto restart; } VATTR_NULL(&vattr); vattr.va_size = 0; if (set_core_nodump_flag) vattr.va_flags = UF_NODUMP; vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); VOP_SETATTR(vp, &vattr, cred); VOP_UNLOCK(vp, 0); vn_finished_write(mp); PROC_LOCK(p); p->p_acflag |= ACORE; PROC_UNLOCK(p); if (p->p_sysent->sv_coredump != NULL) { error = p->p_sysent->sv_coredump(td, vp, limit, compress ? IMGACT_CORE_COMPRESS : 0); } else { error = ENOSYS; } if (locked) { lf.l_type = F_UNLCK; VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); } close: error1 = vn_close(vp, FWRITE, cred, td); if (error == 0) error = error1; out: #ifdef AUDIT audit_proc_coredump(td, name, error); #endif free(name, M_TEMP); return (error); } /* * Nonexistent system call-- signal process (may want to handle it). Flag * error in case process won't see signal immediately (blocked or ignored). */ #ifndef _SYS_SYSPROTO_H_ struct nosys_args { int dummy; }; #endif /* ARGSUSED */ int nosys(td, args) struct thread *td; struct nosys_args *args; { struct proc *p = td->td_proc; PROC_LOCK(p); tdsignal(td, SIGSYS); PROC_UNLOCK(p); return (ENOSYS); } /* * Send a SIGIO or SIGURG signal to a process or process group using stored * credentials rather than those of the current process. */ void pgsigio(sigiop, sig, checkctty) struct sigio **sigiop; int sig, checkctty; { ksiginfo_t ksi; struct sigio *sigio; ksiginfo_init(&ksi); ksi.ksi_signo = sig; ksi.ksi_code = SI_KERNEL; SIGIO_LOCK(); sigio = *sigiop; if (sigio == NULL) { SIGIO_UNLOCK(); return; } if (sigio->sio_pgid > 0) { PROC_LOCK(sigio->sio_proc); if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred)) kern_psignal(sigio->sio_proc, sig); PROC_UNLOCK(sigio->sio_proc); } else if (sigio->sio_pgid < 0) { struct proc *p; PGRP_LOCK(sigio->sio_pgrp); LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) { PROC_LOCK(p); if (p->p_state == PRS_NORMAL && CANSIGIO(sigio->sio_ucred, p->p_ucred) && (checkctty == 0 || (p->p_flag & P_CONTROLT))) kern_psignal(p, sig); PROC_UNLOCK(p); } PGRP_UNLOCK(sigio->sio_pgrp); } SIGIO_UNLOCK(); } static int filt_sigattach(struct knote *kn) { struct proc *p = curproc; kn->kn_ptr.p_proc = p; kn->kn_flags |= EV_CLEAR; /* automatically set */ knlist_add(&p->p_klist, kn, 0); return (0); } static void filt_sigdetach(struct knote *kn) { struct proc *p = kn->kn_ptr.p_proc; knlist_remove(&p->p_klist, kn, 0); } /* * signal knotes are shared with proc knotes, so we apply a mask to * the hint in order to differentiate them from process hints. This * could be avoided by using a signal-specific knote list, but probably * isn't worth the trouble. */ static int filt_signal(struct knote *kn, long hint) { if (hint & NOTE_SIGNAL) { hint &= ~NOTE_SIGNAL; if (kn->kn_id == hint) kn->kn_data++; } return (kn->kn_data != 0); } struct sigacts * sigacts_alloc(void) { struct sigacts *ps; ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO); ps->ps_refcnt = 1; mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF); return (ps); } void sigacts_free(struct sigacts *ps) { mtx_lock(&ps->ps_mtx); ps->ps_refcnt--; if (ps->ps_refcnt == 0) { mtx_destroy(&ps->ps_mtx); free(ps, M_SUBPROC); } else mtx_unlock(&ps->ps_mtx); } struct sigacts * sigacts_hold(struct sigacts *ps) { mtx_lock(&ps->ps_mtx); ps->ps_refcnt++; mtx_unlock(&ps->ps_mtx); return (ps); } void sigacts_copy(struct sigacts *dest, struct sigacts *src) { KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest")); mtx_lock(&src->ps_mtx); bcopy(src, dest, offsetof(struct sigacts, ps_refcnt)); mtx_unlock(&src->ps_mtx); } int sigacts_shared(struct sigacts *ps) { - int shared; - mtx_lock(&ps->ps_mtx); - shared = ps->ps_refcnt > 1; - mtx_unlock(&ps->ps_mtx); - return (shared); + return (ps->ps_refcnt > 1); } Index: stable/10 =================================================================== --- stable/10 (revision 270083) +++ stable/10 (revision 270084) Property changes on: stable/10 ___________________________________________________________________ Modified: svn:mergeinfo ## -0,0 +0,1 ## Merged /head:r268074