From owner-svn-src-stable@FreeBSD.ORG Wed Aug 22 19:53:34 2012 Return-Path: Delivered-To: svn-src-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 22C371065670; Wed, 22 Aug 2012 19:53:34 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id 0C6018FC19; Wed, 22 Aug 2012 19:53:34 +0000 (UTC) Received: from svn.freebsd.org (localhost [127.0.0.1]) by svn.freebsd.org (8.14.4/8.14.4) with ESMTP id q7MJrX3S087843; Wed, 22 Aug 2012 19:53:33 GMT (envelope-from kib@svn.freebsd.org) Received: (from kib@localhost) by svn.freebsd.org (8.14.4/8.14.4/Submit) id q7MJrXRG087835; Wed, 22 Aug 2012 19:53:33 GMT (envelope-from kib@svn.freebsd.org) Message-Id: <201208221953.q7MJrXRG087835@svn.freebsd.org> From: Konstantin Belousov Date: Wed, 22 Aug 2012 19:53:33 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org X-SVN-Group: stable-9 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Subject: svn commit: r239582 - in stable/9/sys: kern nlm sys X-BeenThere: svn-src-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SVN commit messages for all the -stable branches of the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 22 Aug 2012 19:53:34 -0000 Author: kib Date: Wed Aug 22 19:53:33 2012 New Revision: 239582 URL: http://svn.freebsd.org/changeset/base/239582 Log: MFC r239301: Add a sysctl kern.pid_max, which limits the maximum pid the system is allowed to allocate, and corresponding tunable with the same name. Note that existing processes with higher pids are left intact. MFC r239328: Fix grammar. MFC r239329: As a safety measure, disable lowering pid_max too much. Modified: stable/9/sys/kern/init_main.c stable/9/sys/kern/kern_fork.c stable/9/sys/kern/kern_mib.c stable/9/sys/kern/kern_thread.c stable/9/sys/kern/subr_param.c stable/9/sys/nlm/nlm_advlock.c stable/9/sys/sys/proc.h Directory Properties: stable/9/sys/ (props changed) Modified: stable/9/sys/kern/init_main.c ============================================================================== --- stable/9/sys/kern/init_main.c Wed Aug 22 19:45:18 2012 (r239581) +++ stable/9/sys/kern/init_main.c Wed Aug 22 19:53:33 2012 (r239582) @@ -476,6 +476,7 @@ proc0_init(void *dummy __unused) knlist_init_mtx(&p->p_klist, &p->p_mtx); STAILQ_INIT(&p->p_ktr); p->p_nice = NZERO; + /* pid_max cannot be greater than PID_MAX */ td->td_tid = PID_MAX + 1; LIST_INSERT_HEAD(TIDHASH(td->td_tid), td, td_hash); td->td_state = TDS_RUNNING; Modified: stable/9/sys/kern/kern_fork.c ============================================================================== --- stable/9/sys/kern/kern_fork.c Wed Aug 22 19:45:18 2012 (r239581) +++ stable/9/sys/kern/kern_fork.c Wed Aug 22 19:53:33 2012 (r239582) @@ -209,8 +209,8 @@ sysctl_kern_randompid(SYSCTL_HANDLER_ARG pid = randompid; error = sysctl_handle_int(oidp, &pid, 0, req); if (error == 0 && req->newptr != NULL) { - if (pid < 0 || pid > PID_MAX - 100) /* out of range */ - pid = PID_MAX - 100; + if (pid < 0 || pid > pid_max - 100) /* out of range */ + pid = pid_max - 100; else if (pid < 2) /* NOP */ pid = 0; else if (pid < 100) /* Make it reasonable */ @@ -259,8 +259,8 @@ retry: * restart somewhat above 0, as the low-numbered procs * tend to include daemons that don't exit. */ - if (trypid >= PID_MAX) { - trypid = trypid % PID_MAX; + if (trypid >= pid_max) { + trypid = trypid % pid_max; if (trypid < 100) trypid += 100; pidchecked = 0; Modified: stable/9/sys/kern/kern_mib.c ============================================================================== --- stable/9/sys/kern/kern_mib.c Wed Aug 22 19:45:18 2012 (r239581) +++ stable/9/sys/kern/kern_mib.c Wed Aug 22 19:53:33 2012 (r239582) @@ -499,6 +499,34 @@ SYSCTL_INT(_debug_sizeof, OID_AUTO, vnod SYSCTL_INT(_debug_sizeof, OID_AUTO, proc, CTLFLAG_RD, 0, sizeof(struct proc), "sizeof(struct proc)"); +static int +sysctl_kern_pid_max(SYSCTL_HANDLER_ARGS) +{ + int error, pm; + + pm = pid_max; + error = sysctl_handle_int(oidp, &pm, 0, req); + if (error || !req->newptr) + return (error); + sx_xlock(&proctree_lock); + sx_xlock(&allproc_lock); + + /* + * Only permit the values less then PID_MAX. + * As a safety measure, do not allow to limit the pid_max too much. + */ + if (pm < 300 || pm > PID_MAX) + error = EINVAL; + else + pid_max = pm; + sx_xunlock(&allproc_lock); + sx_xunlock(&proctree_lock); + return (error); +} +SYSCTL_PROC(_kern, OID_AUTO, pid_max, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_TUN | + CTLFLAG_MPSAFE, 0, 0, sysctl_kern_pid_max, "I", + "Maximum allowed pid"); + #include #include SYSCTL_INT(_debug_sizeof, OID_AUTO, bio, CTLFLAG_RD, Modified: stable/9/sys/kern/kern_thread.c ============================================================================== --- stable/9/sys/kern/kern_thread.c Wed Aug 22 19:45:18 2012 (r239581) +++ stable/9/sys/kern/kern_thread.c Wed Aug 22 19:53:33 2012 (r239582) @@ -266,7 +266,11 @@ threadinit(void) { mtx_init(&tid_lock, "TID lock", NULL, MTX_DEF); - /* leave one number for thread0 */ + + /* + * pid_max cannot be greater than PID_MAX. + * leave one number for thread0. + */ tid_unrhdr = new_unrhdr(PID_MAX + 2, INT_MAX, &tid_lock); thread_zone = uma_zcreate("THREAD", sched_sizeof_thread(), Modified: stable/9/sys/kern/subr_param.c ============================================================================== --- stable/9/sys/kern/subr_param.c Wed Aug 22 19:45:18 2012 (r239581) +++ stable/9/sys/kern/subr_param.c Wed Aug 22 19:53:33 2012 (r239582) @@ -41,12 +41,13 @@ __FBSDID("$FreeBSD$"); #include "opt_msgbuf.h" #include "opt_maxusers.h" -#include #include #include #include -#include +#include #include +#include +#include #include #include @@ -92,6 +93,7 @@ int ncallout; /* maximum # of timer ev int nbuf; int ngroups_max; /* max # groups per process */ int nswbuf; +pid_t pid_max = PID_MAX; long maxswzone; /* max swmeta KVA storage */ long maxbcache; /* max buffer cache KVA storage */ long maxpipekva; /* Limit on pipe KVA */ @@ -250,6 +252,16 @@ init_param1(void) TUNABLE_INT_FETCH("kern.ngroups", &ngroups_max); if (ngroups_max < NGROUPS_MAX) ngroups_max = NGROUPS_MAX; + + /* + * Only allow to lower the maximal pid. + * Prevent setting up a non-bootable system if pid_max is too low. + */ + TUNABLE_INT_FETCH("kern.pid_max", &pid_max); + if (pid_max > PID_MAX) + pid_max = PID_MAX; + else if (pid_max < 300) + pid_max = 300; } /* Modified: stable/9/sys/nlm/nlm_advlock.c ============================================================================== --- stable/9/sys/nlm/nlm_advlock.c Wed Aug 22 19:45:18 2012 (r239581) +++ stable/9/sys/nlm/nlm_advlock.c Wed Aug 22 19:53:33 2012 (r239582) @@ -98,6 +98,7 @@ nlm_client_init(void *dummy) int i; mtx_init(&nlm_svid_lock, "NLM svid lock", NULL, MTX_DEF); + /* pid_max cannot be greater than PID_MAX */ nlm_svid_allocator = new_unrhdr(PID_MAX + 2, INT_MAX, &nlm_svid_lock); for (i = 0; i < NLM_SVID_HASH_SIZE; i++) LIST_INIT(&nlm_file_svids[i]); Modified: stable/9/sys/sys/proc.h ============================================================================== --- stable/9/sys/sys/proc.h Wed Aug 22 19:45:18 2012 (r239581) +++ stable/9/sys/sys/proc.h Wed Aug 22 19:53:33 2012 (r239582) @@ -693,11 +693,12 @@ MALLOC_DECLARE(M_SUBPROC); #define FIRST_THREAD_IN_PROC(p) TAILQ_FIRST(&(p)->p_threads) /* - * We use process IDs <= PID_MAX; PID_MAX + 1 must also fit in a pid_t, - * as it is used to represent "no process group". + * We use process IDs <= pid_max <= PID_MAX; PID_MAX + 1 must also fit + * in a pid_t, as it is used to represent "no process group". */ #define PID_MAX 99999 #define NO_PID 100000 +extern pid_t pid_max; #define SESS_LEADER(p) ((p)->p_session->s_leader == (p))