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3ada2d599e
freebsd/sys/kern/init_main.c
Konstantin Belousov f7e50ea722 Fix a race between kern_setitimer() and realitexpire(), where the 
callout is started before kern_setitimer() acquires process mutex, but
looses a race and kern_setitimer() gets the process mutex before the
callout.  Then, assuming that new specified struct itimerval has
it_interval zero, but it_value non-zero, the callout, after it starts
executing again, clears p->p_realtimer.it_value, but kern_setitimer()
already rescheduled the callout.

As the result of the race, both p_realtimer is zero, and the callout
is rescheduled. Then, in the exit1(), the exit code sees that it_value
is zero and does not even try to stop the callout. This allows the
struct proc to be reused and eventually the armed callout is
re-initialized.  The consequence is the corrupted callwheel tailq.

Use process mutex to interlock the callout start, which fixes the race.

Reported and tested by:	pho
Reviewed by:	jhb
MFC after:	2 weeks
2012-12-04 20:49:39 +00:00

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/*-
* Copyright (c) 1995 Terrence R. Lambert
* All rights reserved.
*
* Copyright (c) 1982, 1986, 1989, 1991, 1992, 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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.
*
* @(#)init_main.c 8.9 (Berkeley) 1/21/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_ddb.h"
#include "opt_init_path.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/exec.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/jail.h>
#include <sys/ktr.h>
#include <sys/lock.h>
#include <sys/loginclass.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
#include <sys/proc.h>
#include <sys/racct.h>
#include <sys/resourcevar.h>
#include <sys/systm.h>
#include <sys/signalvar.h>
#include <sys/vnode.h>
#include <sys/sysent.h>
#include <sys/reboot.h>
#include <sys/sched.h>
#include <sys/sx.h>
#include <sys/sysproto.h>
#include <sys/vmmeter.h>
#include <sys/unistd.h>
#include <sys/malloc.h>
#include <sys/conf.h>
#include <sys/cpuset.h>
#include <machine/cpu.h>
#include <security/audit/audit.h>
#include <security/mac/mac_framework.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <sys/copyright.h>
#include <ddb/ddb.h>
#include <ddb/db_sym.h>
void mi_startup(void); /* Should be elsewhere */
/* Components of the first process -- never freed. */
static struct session session0;
static struct pgrp pgrp0;
struct proc proc0;
struct thread thread0 __aligned(16);
struct vmspace vmspace0;
struct proc *initproc;
int boothowto = 0; /* initialized so that it can be patched */
SYSCTL_INT(_debug, OID_AUTO, boothowto, CTLFLAG_RD, &boothowto, 0,
"Boot control flags, passed from loader");
int bootverbose;
SYSCTL_INT(_debug, OID_AUTO, bootverbose, CTLFLAG_RW, &bootverbose, 0,
"Control the output of verbose kernel messages");
/*
* This ensures that there is at least one entry so that the sysinit_set
* symbol is not undefined. A sybsystem ID of SI_SUB_DUMMY is never
* executed.
*/
SYSINIT(placeholder, SI_SUB_DUMMY, SI_ORDER_ANY, NULL, NULL);
/*
* The sysinit table itself. Items are checked off as the are run.
* If we want to register new sysinit types, add them to newsysinit.
*/
SET_DECLARE(sysinit_set, struct sysinit);
struct sysinit **sysinit, **sysinit_end;
struct sysinit **newsysinit, **newsysinit_end;
/*
* Merge a new sysinit set into the current set, reallocating it if
* necessary. This can only be called after malloc is running.
*/
void
sysinit_add(struct sysinit **set, struct sysinit **set_end)
{
struct sysinit **newset;
struct sysinit **sipp;
struct sysinit **xipp;
int count;
count = set_end - set;
if (newsysinit)
count += newsysinit_end - newsysinit;
else
count += sysinit_end - sysinit;
newset = malloc(count * sizeof(*sipp), M_TEMP, M_NOWAIT);
if (newset == NULL)
panic("cannot malloc for sysinit");
xipp = newset;
if (newsysinit)
for (sipp = newsysinit; sipp < newsysinit_end; sipp++)
*xipp++ = *sipp;
else
for (sipp = sysinit; sipp < sysinit_end; sipp++)
*xipp++ = *sipp;
for (sipp = set; sipp < set_end; sipp++)
*xipp++ = *sipp;
if (newsysinit)
free(newsysinit, M_TEMP);
newsysinit = newset;
newsysinit_end = newset + count;
}
#if defined (DDB) && defined(VERBOSE_SYSINIT)
static const char *
symbol_name(vm_offset_t va, db_strategy_t strategy)
{
const char *name;
c_db_sym_t sym;
db_expr_t offset;
if (va == 0)
return (NULL);
sym = db_search_symbol(va, strategy, &offset);
if (offset != 0)
return (NULL);
db_symbol_values(sym, &name, NULL);
return (name);
}
#endif
/*
* System startup; initialize the world, create process 0, mount root
* filesystem, and fork to create init and pagedaemon. Most of the
* hard work is done in the lower-level initialization routines including
* startup(), which does memory initialization and autoconfiguration.
*
* This allows simple addition of new kernel subsystems that require
* boot time initialization. It also allows substitution of subsystem
* (for instance, a scheduler, kernel profiler, or VM system) by object
* module. Finally, it allows for optional "kernel threads".
*/
void
mi_startup(void)
{
register struct sysinit **sipp; /* system initialization*/
register struct sysinit **xipp; /* interior loop of sort*/
register struct sysinit *save; /* bubble*/
#if defined(VERBOSE_SYSINIT)
int last;
int verbose;
#endif
if (boothowto & RB_VERBOSE)
bootverbose++;
if (sysinit == NULL) {
sysinit = SET_BEGIN(sysinit_set);
sysinit_end = SET_LIMIT(sysinit_set);
}
restart:
/*
* Perform a bubble sort of the system initialization objects by
* their subsystem (primary key) and order (secondary key).
*/
for (sipp = sysinit; sipp < sysinit_end; sipp++) {
for (xipp = sipp + 1; xipp < sysinit_end; xipp++) {
if ((*sipp)->subsystem < (*xipp)->subsystem ||
((*sipp)->subsystem == (*xipp)->subsystem &&
(*sipp)->order <= (*xipp)->order))
continue; /* skip*/
save = *sipp;
*sipp = *xipp;
*xipp = save;
}
}
#if defined(VERBOSE_SYSINIT)
last = SI_SUB_COPYRIGHT;
verbose = 0;
#if !defined(DDB)
printf("VERBOSE_SYSINIT: DDB not enabled, symbol lookups disabled.\n");
#endif
#endif
/*
* Traverse the (now) ordered list of system initialization tasks.
* Perform each task, and continue on to the next task.
*
* The last item on the list is expected to be the scheduler,
* which will not return.
*/
for (sipp = sysinit; sipp < sysinit_end; sipp++) {
if ((*sipp)->subsystem == SI_SUB_DUMMY)
continue; /* skip dummy task(s)*/
if ((*sipp)->subsystem == SI_SUB_DONE)
continue;
#if defined(VERBOSE_SYSINIT)
if ((*sipp)->subsystem > last) {
verbose = 1;
last = (*sipp)->subsystem;
printf("subsystem %x\n", last);
}
if (verbose) {
#if defined(DDB)
const char *func, *data;
func = symbol_name((vm_offset_t)(*sipp)->func,
DB_STGY_PROC);
data = symbol_name((vm_offset_t)(*sipp)->udata,
DB_STGY_ANY);
if (func != NULL && data != NULL)
printf(" %s(&%s)... ", func, data);
else if (func != NULL)
printf(" %s(%p)... ", func, (*sipp)->udata);
else
#endif
printf(" %p(%p)... ", (*sipp)->func,
(*sipp)->udata);
}
#endif
/* Call function */
(*((*sipp)->func))((*sipp)->udata);
#if defined(VERBOSE_SYSINIT)
if (verbose)
printf("done.\n");
#endif
/* Check off the one we're just done */
(*sipp)->subsystem = SI_SUB_DONE;
/* Check if we've installed more sysinit items via KLD */
if (newsysinit != NULL) {
if (sysinit != SET_BEGIN(sysinit_set))
free(sysinit, M_TEMP);
sysinit = newsysinit;
sysinit_end = newsysinit_end;
newsysinit = NULL;
newsysinit_end = NULL;
goto restart;
}
}
panic("Shouldn't get here!");
/* NOTREACHED*/
}
/*
***************************************************************************
****
**** The following SYSINIT's belong elsewhere, but have not yet
**** been moved.
****
***************************************************************************
*/
static void
print_caddr_t(void *data)
{
printf("%s", (char *)data);
}
static void
print_version(void *data __unused)
{
int len;
/* Strip a trailing newline from version. */
len = strlen(version);
while (len > 0 && version[len - 1] == '\n')
len--;
printf("%.*s %s\n", len, version, machine);
}
SYSINIT(announce, SI_SUB_COPYRIGHT, SI_ORDER_FIRST, print_caddr_t,
copyright);
SYSINIT(trademark, SI_SUB_COPYRIGHT, SI_ORDER_SECOND, print_caddr_t,
trademark);
SYSINIT(version, SI_SUB_COPYRIGHT, SI_ORDER_THIRD, print_version, NULL);
#ifdef WITNESS
static char wit_warn[] =
"WARNING: WITNESS option enabled, expect reduced performance.\n";
SYSINIT(witwarn, SI_SUB_COPYRIGHT, SI_ORDER_THIRD + 1,
print_caddr_t, wit_warn);
SYSINIT(witwarn2, SI_SUB_RUN_SCHEDULER, SI_ORDER_THIRD + 1,
print_caddr_t, wit_warn);
#endif
#ifdef DIAGNOSTIC
static char diag_warn[] =
"WARNING: DIAGNOSTIC option enabled, expect reduced performance.\n";
SYSINIT(diagwarn, SI_SUB_COPYRIGHT, SI_ORDER_THIRD + 2,
print_caddr_t, diag_warn);
SYSINIT(diagwarn2, SI_SUB_RUN_SCHEDULER, SI_ORDER_THIRD + 2,
print_caddr_t, diag_warn);
#endif
static int
null_fetch_syscall_args(struct thread *td __unused,
struct syscall_args *sa __unused)
{
panic("null_fetch_syscall_args");
}
static void
null_set_syscall_retval(struct thread *td __unused, int error __unused)
{
panic("null_set_syscall_retval");
}
struct sysentvec null_sysvec = {
.sv_size = 0,
.sv_table = NULL,
.sv_mask = 0,
.sv_sigsize = 0,
.sv_sigtbl = NULL,
.sv_errsize = 0,
.sv_errtbl = NULL,
.sv_transtrap = NULL,
.sv_fixup = NULL,
.sv_sendsig = NULL,
.sv_sigcode = NULL,
.sv_szsigcode = NULL,
.sv_prepsyscall = NULL,
.sv_name = "null",
.sv_coredump = NULL,
.sv_imgact_try = NULL,
.sv_minsigstksz = 0,
.sv_pagesize = PAGE_SIZE,
.sv_minuser = VM_MIN_ADDRESS,
.sv_maxuser = VM_MAXUSER_ADDRESS,
.sv_usrstack = USRSTACK,
.sv_psstrings = PS_STRINGS,
.sv_stackprot = VM_PROT_ALL,
.sv_copyout_strings = NULL,
.sv_setregs = NULL,
.sv_fixlimit = NULL,
.sv_maxssiz = NULL,
.sv_flags = 0,
.sv_set_syscall_retval = null_set_syscall_retval,
.sv_fetch_syscall_args = null_fetch_syscall_args,
.sv_syscallnames = NULL,
.sv_schedtail = NULL,
};
/*
***************************************************************************
****
**** The two following SYSINIT's are proc0 specific glue code. I am not
**** convinced that they can not be safely combined, but their order of
**** operation has been maintained as the same as the original init_main.c
**** for right now.
****
**** These probably belong in init_proc.c or kern_proc.c, since they
**** deal with proc0 (the fork template process).
****
***************************************************************************
*/
/* ARGSUSED*/
static void
proc0_init(void *dummy __unused)
{
struct proc *p;
struct thread *td;
vm_paddr_t pageablemem;
int i;
GIANT_REQUIRED;
p = &proc0;
td = &thread0;
/*
* Initialize magic number and osrel.
*/
p->p_magic = P_MAGIC;
p->p_osrel = osreldate;
/*
* Initialize thread and process structures.
*/
procinit(); /* set up proc zone */
threadinit(); /* set up UMA zones */
/*
* Initialise scheduler resources.
* Add scheduler specific parts to proc, thread as needed.
*/
schedinit(); /* scheduler gets its house in order */
/*
* Initialize sleep queue hash table
*/
sleepinit();
/*
* additional VM structures
*/
vm_init2();
/*
* Create process 0 (the swapper).
*/
LIST_INSERT_HEAD(&allproc, p, p_list);
LIST_INSERT_HEAD(PIDHASH(0), p, p_hash);
mtx_init(&pgrp0.pg_mtx, "process group", NULL, MTX_DEF | MTX_DUPOK);
p->p_pgrp = &pgrp0;
LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash);
LIST_INIT(&pgrp0.pg_members);
LIST_INSERT_HEAD(&pgrp0.pg_members, p, p_pglist);
pgrp0.pg_session = &session0;
mtx_init(&session0.s_mtx, "session", NULL, MTX_DEF);
refcount_init(&session0.s_count, 1);
session0.s_leader = p;
p->p_sysent = &null_sysvec;
p->p_flag = P_SYSTEM | P_INMEM;
p->p_state = PRS_NORMAL;
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;
td->td_pri_class = PRI_TIMESHARE;
td->td_user_pri = PUSER;
td->td_base_user_pri = PUSER;
td->td_lend_user_pri = PRI_MAX;
td->td_priority = PVM;
td->td_base_pri = PVM;
td->td_oncpu = 0;
td->td_flags = TDF_INMEM;
td->td_pflags = TDP_KTHREAD;
td->td_cpuset = cpuset_thread0();
prison0.pr_cpuset = cpuset_ref(td->td_cpuset);
p->p_peers = 0;
p->p_leader = p;
strncpy(p->p_comm, "kernel", sizeof (p->p_comm));
strncpy(td->td_name, "swapper", sizeof (td->td_name));
callout_init_mtx(&p->p_itcallout, &p->p_mtx, 0);
callout_init_mtx(&p->p_limco, &p->p_mtx, 0);
callout_init(&td->td_slpcallout, CALLOUT_MPSAFE);
/* Create credentials. */
p->p_ucred = crget();
p->p_ucred->cr_ngroups = 1; /* group 0 */
p->p_ucred->cr_uidinfo = uifind(0);
p->p_ucred->cr_ruidinfo = uifind(0);
p->p_ucred->cr_prison = &prison0;
p->p_ucred->cr_loginclass = loginclass_find("default");
#ifdef AUDIT
audit_cred_kproc0(p->p_ucred);
#endif
#ifdef MAC
mac_cred_create_swapper(p->p_ucred);
#endif
td->td_ucred = crhold(p->p_ucred);
/* Create sigacts. */
p->p_sigacts = sigacts_alloc();
/* Initialize signal state for process 0. */
siginit(&proc0);
/* Create the file descriptor table. */
p->p_fd = fdinit(NULL);
p->p_fdtol = NULL;
/* Create the limits structures. */
p->p_limit = lim_alloc();
for (i = 0; i < RLIM_NLIMITS; i++)
p->p_limit->pl_rlimit[i].rlim_cur =
p->p_limit->pl_rlimit[i].rlim_max = RLIM_INFINITY;
p->p_limit->pl_rlimit[RLIMIT_NOFILE].rlim_cur =
p->p_limit->pl_rlimit[RLIMIT_NOFILE].rlim_max = maxfiles;
p->p_limit->pl_rlimit[RLIMIT_NPROC].rlim_cur =
p->p_limit->pl_rlimit[RLIMIT_NPROC].rlim_max = maxproc;
p->p_limit->pl_rlimit[RLIMIT_DATA].rlim_cur = dfldsiz;
p->p_limit->pl_rlimit[RLIMIT_DATA].rlim_max = maxdsiz;
p->p_limit->pl_rlimit[RLIMIT_STACK].rlim_cur = dflssiz;
p->p_limit->pl_rlimit[RLIMIT_STACK].rlim_max = maxssiz;
/* Cast to avoid overflow on i386/PAE. */
pageablemem = ptoa((vm_paddr_t)cnt.v_free_count);
p->p_limit->pl_rlimit[RLIMIT_RSS].rlim_cur =
p->p_limit->pl_rlimit[RLIMIT_RSS].rlim_max = pageablemem;
p->p_limit->pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = pageablemem / 3;
p->p_limit->pl_rlimit[RLIMIT_MEMLOCK].rlim_max = pageablemem;
p->p_cpulimit = RLIM_INFINITY;
/* Initialize resource accounting structures. */
racct_create(&p->p_racct);
p->p_stats = pstats_alloc();
/* Allocate a prototype map so we have something to fork. */
pmap_pinit0(vmspace_pmap(&vmspace0));
p->p_vmspace = &vmspace0;
vmspace0.vm_refcnt = 1;
/*
* proc0 is not expected to enter usermode, so there is no special
* handling for sv_minuser here, like is done for exec_new_vmspace().
*/
vm_map_init(&vmspace0.vm_map, vmspace_pmap(&vmspace0),
p->p_sysent->sv_minuser, p->p_sysent->sv_maxuser);
/*
* Call the init and ctor for the new thread and proc. We wait
* to do this until all other structures are fairly sane.
*/
EVENTHANDLER_INVOKE(process_init, p);
EVENTHANDLER_INVOKE(thread_init, td);
EVENTHANDLER_INVOKE(process_ctor, p);
EVENTHANDLER_INVOKE(thread_ctor, td);
/*
* Charge root for one process.
*/
(void)chgproccnt(p->p_ucred->cr_ruidinfo, 1, 0);
PROC_LOCK(p);
racct_add_force(p, RACCT_NPROC, 1);
PROC_UNLOCK(p);
}
SYSINIT(p0init, SI_SUB_INTRINSIC, SI_ORDER_FIRST, proc0_init, NULL);
/* ARGSUSED*/
static void
proc0_post(void *dummy __unused)
{
struct timespec ts;
struct proc *p;
struct rusage ru;
struct thread *td;
/*
* Now we can look at the time, having had a chance to verify the
* time from the filesystem. Pretend that proc0 started now.
*/
sx_slock(&allproc_lock);
FOREACH_PROC_IN_SYSTEM(p) {
microuptime(&p->p_stats->p_start);
PROC_SLOCK(p);
rufetch(p, &ru); /* Clears thread stats */
PROC_SUNLOCK(p);
p->p_rux.rux_runtime = 0;
p->p_rux.rux_uticks = 0;
p->p_rux.rux_sticks = 0;
p->p_rux.rux_iticks = 0;
FOREACH_THREAD_IN_PROC(p, td) {
td->td_runtime = 0;
}
}
sx_sunlock(&allproc_lock);
PCPU_SET(switchtime, cpu_ticks());
PCPU_SET(switchticks, ticks);
/*
* Give the ``random'' number generator a thump.
*/
nanotime(&ts);
srandom(ts.tv_sec ^ ts.tv_nsec);
}
SYSINIT(p0post, SI_SUB_INTRINSIC_POST, SI_ORDER_FIRST, proc0_post, NULL);
static void
random_init(void *dummy __unused)
{
/*
* After CPU has been started we have some randomness on most
* platforms via get_cyclecount(). For platforms that don't
* we will reseed random(9) in proc0_post() as well.
*/
srandom(get_cyclecount());
}
SYSINIT(random, SI_SUB_RANDOM, SI_ORDER_FIRST, random_init, NULL);
/*
***************************************************************************
****
**** The following SYSINIT's and glue code should be moved to the
**** respective files on a per subsystem basis.
****
***************************************************************************
*/
/*
***************************************************************************
****
**** The following code probably belongs in another file, like
**** kern/init_init.c.
****
***************************************************************************
*/
/*
* List of paths to try when searching for "init".
*/
static char init_path[MAXPATHLEN] =
#ifdef INIT_PATH
__XSTRING(INIT_PATH);
#else
"/sbin/init:/sbin/oinit:/sbin/init.bak:/rescue/init";
#endif
SYSCTL_STRING(_kern, OID_AUTO, init_path, CTLFLAG_RD, init_path, 0,
"Path used to search the init process");
/*
* Shutdown timeout of init(8).
* Unused within kernel, but used to control init(8), hence do not remove.
*/
#ifndef INIT_SHUTDOWN_TIMEOUT
#define INIT_SHUTDOWN_TIMEOUT 120
#endif
static int init_shutdown_timeout = INIT_SHUTDOWN_TIMEOUT;
SYSCTL_INT(_kern, OID_AUTO, init_shutdown_timeout,
CTLFLAG_RW, &init_shutdown_timeout, 0, "Shutdown timeout of init(8). "
"Unused within kernel, but used to control init(8)");
/*
* Start the initial user process; try exec'ing each pathname in init_path.
* The program is invoked with one argument containing the boot flags.
*/
static void
start_init(void *dummy)
{
vm_offset_t addr;
struct execve_args args;
int options, error;
char *var, *path, *next, *s;
char *ucp, **uap, *arg0, *arg1;
struct thread *td;
struct proc *p;
mtx_lock(&Giant);
GIANT_REQUIRED;
td = curthread;
p = td->td_proc;
vfs_mountroot();
/*
* Need just enough stack to hold the faked-up "execve()" arguments.
*/
addr = p->p_sysent->sv_usrstack - PAGE_SIZE;
if (vm_map_find(&p->p_vmspace->vm_map, NULL, 0, &addr, PAGE_SIZE,
FALSE, VM_PROT_ALL, VM_PROT_ALL, 0) != 0)
panic("init: couldn't allocate argument space");
p->p_vmspace->vm_maxsaddr = (caddr_t)addr;
p->p_vmspace->vm_ssize = 1;
if ((var = getenv("init_path")) != NULL) {
strlcpy(init_path, var, sizeof(init_path));
freeenv(var);
}
for (path = init_path; *path != '\0'; path = next) {
while (*path == ':')
path++;
if (*path == '\0')
break;
for (next = path; *next != '\0' && *next != ':'; next++)
/* nothing */ ;
if (bootverbose)
printf("start_init: trying %.*s\n", (int)(next - path),
path);
/*
* Move out the boot flag argument.
*/
options = 0;
ucp = (char *)p->p_sysent->sv_usrstack;
(void)subyte(--ucp, 0); /* trailing zero */
if (boothowto & RB_SINGLE) {
(void)subyte(--ucp, 's');
options = 1;
}
#ifdef notyet
if (boothowto & RB_FASTBOOT) {
(void)subyte(--ucp, 'f');
options = 1;
}
#endif
#ifdef BOOTCDROM
(void)subyte(--ucp, 'C');
options = 1;
#endif
if (options == 0)
(void)subyte(--ucp, '-');
(void)subyte(--ucp, '-'); /* leading hyphen */
arg1 = ucp;
/*
* Move out the file name (also arg 0).
*/
(void)subyte(--ucp, 0);
for (s = next - 1; s >= path; s--)
(void)subyte(--ucp, *s);
arg0 = ucp;
/*
* Move out the arg pointers.
*/
uap = (char **)((intptr_t)ucp & ~(sizeof(intptr_t)-1));
(void)suword((caddr_t)--uap, (long)0); /* terminator */
(void)suword((caddr_t)--uap, (long)(intptr_t)arg1);
(void)suword((caddr_t)--uap, (long)(intptr_t)arg0);
/*
* Point at the arguments.
*/
args.fname = arg0;
args.argv = uap;
args.envv = NULL;
/*
* Now try to exec the program. If can't for any reason
* other than it doesn't exist, complain.
*
* Otherwise, return via fork_trampoline() all the way
* to user mode as init!
*/
if ((error = sys_execve(td, &args)) == 0) {
mtx_unlock(&Giant);
return;
}
if (error != ENOENT)
printf("exec %.*s: error %d\n", (int)(next - path),
path, error);
}
printf("init: not found in path %s\n", init_path);
panic("no init");
}
/*
* Like kproc_create(), but runs in it's own address space.
* We do this early to reserve pid 1.
*
* Note special case - do not make it runnable yet. Other work
* in progress will change this more.
*/
static void
create_init(const void *udata __unused)
{
struct ucred *newcred, *oldcred;
int error;
error = fork1(&thread0, RFFDG | RFPROC | RFSTOPPED, 0, &initproc,
NULL, 0);
if (error)
panic("cannot fork init: %d\n", error);
KASSERT(initproc->p_pid == 1, ("create_init: initproc->p_pid != 1"));
/* divorce init's credentials from the kernel's */
newcred = crget();
PROC_LOCK(initproc);
initproc->p_flag |= P_SYSTEM | P_INMEM;
oldcred = initproc->p_ucred;
crcopy(newcred, oldcred);
#ifdef MAC
mac_cred_create_init(newcred);
#endif
#ifdef AUDIT
audit_cred_proc1(newcred);
#endif
initproc->p_ucred = newcred;
PROC_UNLOCK(initproc);
crfree(oldcred);
cred_update_thread(FIRST_THREAD_IN_PROC(initproc));
cpu_set_fork_handler(FIRST_THREAD_IN_PROC(initproc), start_init, NULL);
}
SYSINIT(init, SI_SUB_CREATE_INIT, SI_ORDER_FIRST, create_init, NULL);
/*
* Make it runnable now.
*/
static void
kick_init(const void *udata __unused)
{
struct thread *td;
td = FIRST_THREAD_IN_PROC(initproc);
thread_lock(td);
TD_SET_CAN_RUN(td);
sched_add(td, SRQ_BORING);
thread_unlock(td);
}
SYSINIT(kickinit, SI_SUB_KTHREAD_INIT, SI_ORDER_FIRST, kick_init, NULL);
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