freebsd-dev/sys/kern/kern_shutdown.c
Pawel Jakub Dawidek 5ebb15b942 Add missing privilege check when setting the dump device. Before that change it
was possible for a regular user to setup the dump device if he had write access
to the given device. In theory it is a security issue as user might get access
to kernel's memory after provoking kernel crash, but in practise it is not
recommended to give regular users direct access to storage devices.

Rework the code so that we do privileges check within the set_dumper() function
to avoid similar problems in the future.

Discussed with:	secteam
2014-11-11 04:48:09 +00:00

891 lines
22 KiB
C

/*-
* Copyright (c) 1986, 1988, 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_shutdown.c 8.3 (Berkeley) 1/21/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_ddb.h"
#include "opt_kdb.h"
#include "opt_panic.h"
#include "opt_sched.h"
#include "opt_watchdog.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/cons.h>
#include <sys/eventhandler.h>
#include <sys/jail.h>
#include <sys/kdb.h>
#include <sys/kernel.h>
#include <sys/kerneldump.h>
#include <sys/kthread.h>
#include <sys/ktr.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/reboot.h>
#include <sys/resourcevar.h>
#include <sys/rwlock.h>
#include <sys/sched.h>
#include <sys/smp.h>
#include <sys/sysctl.h>
#include <sys/sysproto.h>
#include <sys/vnode.h>
#include <sys/watchdog.h>
#include <ddb/ddb.h>
#include <machine/cpu.h>
#include <machine/pcb.h>
#include <machine/smp.h>
#include <security/mac/mac_framework.h>
#include <vm/vm.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>
#include <vm/swap_pager.h>
#include <sys/signalvar.h>
#ifndef PANIC_REBOOT_WAIT_TIME
#define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
#endif
static int panic_reboot_wait_time = PANIC_REBOOT_WAIT_TIME;
SYSCTL_INT(_kern, OID_AUTO, panic_reboot_wait_time, CTLFLAG_RWTUN,
&panic_reboot_wait_time, 0,
"Seconds to wait before rebooting after a panic");
/*
* Note that stdarg.h and the ANSI style va_start macro is used for both
* ANSI and traditional C compilers.
*/
#include <machine/stdarg.h>
#ifdef KDB
#ifdef KDB_UNATTENDED
int debugger_on_panic = 0;
#else
int debugger_on_panic = 1;
#endif
SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic,
CTLFLAG_RWTUN | CTLFLAG_SECURE,
&debugger_on_panic, 0, "Run debugger on kernel panic");
#ifdef KDB_TRACE
static int trace_on_panic = 1;
#else
static int trace_on_panic = 0;
#endif
SYSCTL_INT(_debug, OID_AUTO, trace_on_panic,
CTLFLAG_RWTUN | CTLFLAG_SECURE,
&trace_on_panic, 0, "Print stack trace on kernel panic");
#endif /* KDB */
static int sync_on_panic = 0;
SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RWTUN,
&sync_on_panic, 0, "Do a sync before rebooting from a panic");
static SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0,
"Shutdown environment");
#ifndef DIAGNOSTIC
static int show_busybufs;
#else
static int show_busybufs = 1;
#endif
SYSCTL_INT(_kern_shutdown, OID_AUTO, show_busybufs, CTLFLAG_RW,
&show_busybufs, 0, "");
/*
* Variable panicstr contains argument to first call to panic; used as flag
* to indicate that the kernel has already called panic.
*/
const char *panicstr;
int dumping; /* system is dumping */
int rebooting; /* system is rebooting */
static struct dumperinfo dumper; /* our selected dumper */
/* Context information for dump-debuggers. */
static struct pcb dumppcb; /* Registers. */
lwpid_t dumptid; /* Thread ID. */
static void poweroff_wait(void *, int);
static void shutdown_halt(void *junk, int howto);
static void shutdown_panic(void *junk, int howto);
static void shutdown_reset(void *junk, int howto);
static void vpanic(const char *fmt, va_list ap) __dead2;
/* register various local shutdown events */
static void
shutdown_conf(void *unused)
{
EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL,
SHUTDOWN_PRI_FIRST);
EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL,
SHUTDOWN_PRI_LAST + 100);
EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL,
SHUTDOWN_PRI_LAST + 100);
EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL,
SHUTDOWN_PRI_LAST + 200);
}
SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL);
/*
* The system call that results in a reboot.
*/
/* ARGSUSED */
int
sys_reboot(struct thread *td, struct reboot_args *uap)
{
int error;
error = 0;
#ifdef MAC
error = mac_system_check_reboot(td->td_ucred, uap->opt);
#endif
if (error == 0)
error = priv_check(td, PRIV_REBOOT);
if (error == 0) {
mtx_lock(&Giant);
kern_reboot(uap->opt);
mtx_unlock(&Giant);
}
return (error);
}
/*
* Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC
*/
void
shutdown_nice(int howto)
{
if (initproc != NULL) {
/* Send a signal to init(8) and have it shutdown the world. */
PROC_LOCK(initproc);
if (howto & RB_POWEROFF)
kern_psignal(initproc, SIGUSR2);
else if (howto & RB_HALT)
kern_psignal(initproc, SIGUSR1);
else
kern_psignal(initproc, SIGINT);
PROC_UNLOCK(initproc);
} else {
/* No init(8) running, so simply reboot. */
kern_reboot(howto | RB_NOSYNC);
}
}
static void
print_uptime(void)
{
int f;
struct timespec ts;
getnanouptime(&ts);
printf("Uptime: ");
f = 0;
if (ts.tv_sec >= 86400) {
printf("%ldd", (long)ts.tv_sec / 86400);
ts.tv_sec %= 86400;
f = 1;
}
if (f || ts.tv_sec >= 3600) {
printf("%ldh", (long)ts.tv_sec / 3600);
ts.tv_sec %= 3600;
f = 1;
}
if (f || ts.tv_sec >= 60) {
printf("%ldm", (long)ts.tv_sec / 60);
ts.tv_sec %= 60;
f = 1;
}
printf("%lds\n", (long)ts.tv_sec);
}
int
doadump(boolean_t textdump)
{
boolean_t coredump;
int error;
error = 0;
if (dumping)
return (EBUSY);
if (dumper.dumper == NULL)
return (ENXIO);
savectx(&dumppcb);
dumptid = curthread->td_tid;
dumping++;
coredump = TRUE;
#ifdef DDB
if (textdump && textdump_pending) {
coredump = FALSE;
textdump_dumpsys(&dumper);
}
#endif
if (coredump)
error = dumpsys(&dumper);
dumping--;
return (error);
}
static int
isbufbusy(struct buf *bp)
{
if (((bp->b_flags & (B_INVAL | B_PERSISTENT)) == 0 &&
BUF_ISLOCKED(bp)) ||
((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI))
return (1);
return (0);
}
/*
* Shutdown the system cleanly to prepare for reboot, halt, or power off.
*/
void
kern_reboot(int howto)
{
static int first_buf_printf = 1;
static int waittime = -1;
#if defined(SMP)
/*
* Bind us to CPU 0 so that all shutdown code runs there. Some
* systems don't shutdown properly (i.e., ACPI power off) if we
* run on another processor.
*/
if (!SCHEDULER_STOPPED()) {
thread_lock(curthread);
sched_bind(curthread, 0);
thread_unlock(curthread);
KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0"));
}
#endif
/* We're in the process of rebooting. */
rebooting = 1;
/* We are out of the debugger now. */
kdb_active = 0;
/*
* Do any callouts that should be done BEFORE syncing the filesystems.
*/
EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
/*
* Now sync filesystems
*/
if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
register struct buf *bp;
int iter, nbusy, pbusy;
#ifndef PREEMPTION
int subiter;
#endif
waittime = 0;
wdog_kern_pat(WD_LASTVAL);
sys_sync(curthread, NULL);
/*
* With soft updates, some buffers that are
* written will be remarked as dirty until other
* buffers are written.
*/
for (iter = pbusy = 0; iter < 20; iter++) {
nbusy = 0;
for (bp = &buf[nbuf]; --bp >= buf; )
if (isbufbusy(bp))
nbusy++;
if (nbusy == 0) {
if (first_buf_printf)
printf("All buffers synced.");
break;
}
if (first_buf_printf) {
printf("Syncing disks, buffers remaining... ");
first_buf_printf = 0;
}
printf("%d ", nbusy);
if (nbusy < pbusy)
iter = 0;
pbusy = nbusy;
wdog_kern_pat(WD_LASTVAL);
sys_sync(curthread, NULL);
#ifdef PREEMPTION
/*
* Drop Giant and spin for a while to allow
* interrupt threads to run.
*/
DROP_GIANT();
DELAY(50000 * iter);
PICKUP_GIANT();
#else
/*
* Drop Giant and context switch several times to
* allow interrupt threads to run.
*/
DROP_GIANT();
for (subiter = 0; subiter < 50 * iter; subiter++) {
thread_lock(curthread);
mi_switch(SW_VOL, NULL);
thread_unlock(curthread);
DELAY(1000);
}
PICKUP_GIANT();
#endif
}
printf("\n");
/*
* Count only busy local buffers to prevent forcing
* a fsck if we're just a client of a wedged NFS server
*/
nbusy = 0;
for (bp = &buf[nbuf]; --bp >= buf; ) {
if (isbufbusy(bp)) {
#if 0
/* XXX: This is bogus. We should probably have a BO_REMOTE flag instead */
if (bp->b_dev == NULL) {
TAILQ_REMOVE(&mountlist,
bp->b_vp->v_mount, mnt_list);
continue;
}
#endif
nbusy++;
if (show_busybufs > 0) {
printf(
"%d: buf:%p, vnode:%p, flags:%0x, blkno:%jd, lblkno:%jd, buflock:",
nbusy, bp, bp->b_vp, bp->b_flags,
(intmax_t)bp->b_blkno,
(intmax_t)bp->b_lblkno);
BUF_LOCKPRINTINFO(bp);
if (show_busybufs > 1)
vn_printf(bp->b_vp,
"vnode content: ");
}
}
}
if (nbusy) {
/*
* Failed to sync all blocks. Indicate this and don't
* unmount filesystems (thus forcing an fsck on reboot).
*/
printf("Giving up on %d buffers\n", nbusy);
DELAY(5000000); /* 5 seconds */
} else {
if (!first_buf_printf)
printf("Final sync complete\n");
/*
* Unmount filesystems
*/
if (panicstr == 0)
vfs_unmountall();
}
swapoff_all();
DELAY(100000); /* wait for console output to finish */
}
print_uptime();
cngrab();
/*
* Ok, now do things that assume all filesystem activity has
* been completed.
*/
EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping)
doadump(TRUE);
/* Now that we're going to really halt the system... */
EVENTHANDLER_INVOKE(shutdown_final, howto);
for(;;) ; /* safety against shutdown_reset not working */
/* NOTREACHED */
}
/*
* If the shutdown was a clean halt, behave accordingly.
*/
static void
shutdown_halt(void *junk, int howto)
{
if (howto & RB_HALT) {
printf("\n");
printf("The operating system has halted.\n");
printf("Please press any key to reboot.\n\n");
switch (cngetc()) {
case -1: /* No console, just die */
cpu_halt();
/* NOTREACHED */
default:
howto &= ~RB_HALT;
break;
}
}
}
/*
* Check to see if the system paniced, pause and then reboot
* according to the specified delay.
*/
static void
shutdown_panic(void *junk, int howto)
{
int loop;
if (howto & RB_DUMP) {
if (panic_reboot_wait_time != 0) {
if (panic_reboot_wait_time != -1) {
printf("Automatic reboot in %d seconds - "
"press a key on the console to abort\n",
panic_reboot_wait_time);
for (loop = panic_reboot_wait_time * 10;
loop > 0; --loop) {
DELAY(1000 * 100); /* 1/10th second */
/* Did user type a key? */
if (cncheckc() != -1)
break;
}
if (!loop)
return;
}
} else { /* zero time specified - reboot NOW */
return;
}
printf("--> Press a key on the console to reboot,\n");
printf("--> or switch off the system now.\n");
cngetc();
}
}
/*
* Everything done, now reset
*/
static void
shutdown_reset(void *junk, int howto)
{
printf("Rebooting...\n");
DELAY(1000000); /* wait 1 sec for printf's to complete and be read */
/*
* Acquiring smp_ipi_mtx here has a double effect:
* - it disables interrupts avoiding CPU0 preemption
* by fast handlers (thus deadlocking against other CPUs)
* - it avoids deadlocks against smp_rendezvous() or, more
* generally, threads busy-waiting, with this spinlock held,
* and waiting for responses by threads on other CPUs
* (ie. smp_tlb_shootdown()).
*
* For the !SMP case it just needs to handle the former problem.
*/
#ifdef SMP
mtx_lock_spin(&smp_ipi_mtx);
#else
spinlock_enter();
#endif
/* cpu_boot(howto); */ /* doesn't do anything at the moment */
cpu_reset();
/* NOTREACHED */ /* assuming reset worked */
}
#if defined(WITNESS) || defined(INVARIANTS)
static int kassert_warn_only = 0;
#ifdef KDB
static int kassert_do_kdb = 0;
#endif
#ifdef KTR
static int kassert_do_ktr = 0;
#endif
static int kassert_do_log = 1;
static int kassert_log_pps_limit = 4;
static int kassert_log_mute_at = 0;
static int kassert_log_panic_at = 0;
static int kassert_warnings = 0;
SYSCTL_NODE(_debug, OID_AUTO, kassert, CTLFLAG_RW, NULL, "kassert options");
SYSCTL_INT(_debug_kassert, OID_AUTO, warn_only, CTLFLAG_RWTUN,
&kassert_warn_only, 0,
"KASSERT triggers a panic (1) or just a warning (0)");
#ifdef KDB
SYSCTL_INT(_debug_kassert, OID_AUTO, do_kdb, CTLFLAG_RWTUN,
&kassert_do_kdb, 0, "KASSERT will enter the debugger");
#endif
#ifdef KTR
SYSCTL_UINT(_debug_kassert, OID_AUTO, do_ktr, CTLFLAG_RWTUN,
&kassert_do_ktr, 0,
"KASSERT does a KTR, set this to the KTRMASK you want");
#endif
SYSCTL_INT(_debug_kassert, OID_AUTO, do_log, CTLFLAG_RWTUN,
&kassert_do_log, 0, "KASSERT triggers a panic (1) or just a warning (0)");
SYSCTL_INT(_debug_kassert, OID_AUTO, warnings, CTLFLAG_RWTUN,
&kassert_warnings, 0, "number of KASSERTs that have been triggered");
SYSCTL_INT(_debug_kassert, OID_AUTO, log_panic_at, CTLFLAG_RWTUN,
&kassert_log_panic_at, 0, "max number of KASSERTS before we will panic");
SYSCTL_INT(_debug_kassert, OID_AUTO, log_pps_limit, CTLFLAG_RWTUN,
&kassert_log_pps_limit, 0, "limit number of log messages per second");
SYSCTL_INT(_debug_kassert, OID_AUTO, log_mute_at, CTLFLAG_RWTUN,
&kassert_log_mute_at, 0, "max number of KASSERTS to log");
static int kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS);
SYSCTL_PROC(_debug_kassert, OID_AUTO, kassert,
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0,
kassert_sysctl_kassert, "I", "set to trigger a test kassert");
static int
kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS)
{
int error, i;
error = sysctl_wire_old_buffer(req, sizeof(int));
if (error == 0) {
i = 0;
error = sysctl_handle_int(oidp, &i, 0, req);
}
if (error != 0 || req->newptr == NULL)
return (error);
KASSERT(0, ("kassert_sysctl_kassert triggered kassert %d", i));
return (0);
}
/*
* Called by KASSERT, this decides if we will panic
* or if we will log via printf and/or ktr.
*/
void
kassert_panic(const char *fmt, ...)
{
static char buf[256];
va_list ap;
va_start(ap, fmt);
(void)vsnprintf(buf, sizeof(buf), fmt, ap);
va_end(ap);
/*
* panic if we're not just warning, or if we've exceeded
* kassert_log_panic_at warnings.
*/
if (!kassert_warn_only ||
(kassert_log_panic_at > 0 &&
kassert_warnings >= kassert_log_panic_at)) {
va_start(ap, fmt);
vpanic(fmt, ap);
/* NORETURN */
}
#ifdef KTR
if (kassert_do_ktr)
CTR0(ktr_mask, buf);
#endif /* KTR */
/*
* log if we've not yet met the mute limit.
*/
if (kassert_do_log &&
(kassert_log_mute_at == 0 ||
kassert_warnings < kassert_log_mute_at)) {
static struct timeval lasterr;
static int curerr;
if (ppsratecheck(&lasterr, &curerr, kassert_log_pps_limit)) {
printf("KASSERT failed: %s\n", buf);
kdb_backtrace();
}
}
#ifdef KDB
if (kassert_do_kdb) {
kdb_enter(KDB_WHY_KASSERT, buf);
}
#endif
atomic_add_int(&kassert_warnings, 1);
}
#endif
/*
* Panic is called on unresolvable fatal errors. It prints "panic: mesg",
* and then reboots. If we are called twice, then we avoid trying to sync
* the disks as this often leads to recursive panics.
*/
void
panic(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vpanic(fmt, ap);
}
static void
vpanic(const char *fmt, va_list ap)
{
#ifdef SMP
cpuset_t other_cpus;
#endif
struct thread *td = curthread;
int bootopt, newpanic;
static char buf[256];
spinlock_enter();
#ifdef SMP
/*
* stop_cpus_hard(other_cpus) should prevent multiple CPUs from
* concurrently entering panic. Only the winner will proceed
* further.
*/
if (panicstr == NULL && !kdb_active) {
other_cpus = all_cpus;
CPU_CLR(PCPU_GET(cpuid), &other_cpus);
stop_cpus_hard(other_cpus);
}
/*
* We set stop_scheduler here and not in the block above,
* because we want to ensure that if panic has been called and
* stop_scheduler_on_panic is true, then stop_scheduler will
* always be set. Even if panic has been entered from kdb.
*/
td->td_stopsched = 1;
#endif
bootopt = RB_AUTOBOOT;
newpanic = 0;
if (panicstr)
bootopt |= RB_NOSYNC;
else {
bootopt |= RB_DUMP;
panicstr = fmt;
newpanic = 1;
}
if (newpanic) {
(void)vsnprintf(buf, sizeof(buf), fmt, ap);
panicstr = buf;
cngrab();
printf("panic: %s\n", buf);
} else {
printf("panic: ");
vprintf(fmt, ap);
printf("\n");
}
#ifdef SMP
printf("cpuid = %d\n", PCPU_GET(cpuid));
#endif
#ifdef KDB
if (newpanic && trace_on_panic)
kdb_backtrace();
if (debugger_on_panic)
kdb_enter(KDB_WHY_PANIC, "panic");
#endif
/*thread_lock(td); */
td->td_flags |= TDF_INPANIC;
/* thread_unlock(td); */
if (!sync_on_panic)
bootopt |= RB_NOSYNC;
kern_reboot(bootopt);
}
/*
* Support for poweroff delay.
*
* Please note that setting this delay too short might power off your machine
* before the write cache on your hard disk has been flushed, leading to
* soft-updates inconsistencies.
*/
#ifndef POWEROFF_DELAY
# define POWEROFF_DELAY 5000
#endif
static int poweroff_delay = POWEROFF_DELAY;
SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
&poweroff_delay, 0, "Delay before poweroff to write disk caches (msec)");
static void
poweroff_wait(void *junk, int howto)
{
if (!(howto & RB_POWEROFF) || poweroff_delay <= 0)
return;
DELAY(poweroff_delay * 1000);
}
/*
* Some system processes (e.g. syncer) need to be stopped at appropriate
* points in their main loops prior to a system shutdown, so that they
* won't interfere with the shutdown process (e.g. by holding a disk buf
* to cause sync to fail). For each of these system processes, register
* shutdown_kproc() as a handler for one of shutdown events.
*/
static int kproc_shutdown_wait = 60;
SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
&kproc_shutdown_wait, 0, "Max wait time (sec) to stop for each process");
void
kproc_shutdown(void *arg, int howto)
{
struct proc *p;
int error;
if (panicstr)
return;
p = (struct proc *)arg;
printf("Waiting (max %d seconds) for system process `%s' to stop...",
kproc_shutdown_wait, p->p_comm);
error = kproc_suspend(p, kproc_shutdown_wait * hz);
if (error == EWOULDBLOCK)
printf("timed out\n");
else
printf("done\n");
}
void
kthread_shutdown(void *arg, int howto)
{
struct thread *td;
int error;
if (panicstr)
return;
td = (struct thread *)arg;
printf("Waiting (max %d seconds) for system thread `%s' to stop...",
kproc_shutdown_wait, td->td_name);
error = kthread_suspend(td, kproc_shutdown_wait * hz);
if (error == EWOULDBLOCK)
printf("timed out\n");
else
printf("done\n");
}
static char dumpdevname[sizeof(((struct cdev*)NULL)->si_name)];
SYSCTL_STRING(_kern_shutdown, OID_AUTO, dumpdevname, CTLFLAG_RD,
dumpdevname, 0, "Device for kernel dumps");
/* Registration of dumpers */
int
set_dumper(struct dumperinfo *di, const char *devname, struct thread *td)
{
size_t wantcopy;
int error;
error = priv_check(td, PRIV_SETDUMPER);
if (error != 0)
return (error);
if (di == NULL) {
bzero(&dumper, sizeof dumper);
dumpdevname[0] = '\0';
return (0);
}
if (dumper.dumper != NULL)
return (EBUSY);
dumper = *di;
wantcopy = strlcpy(dumpdevname, devname, sizeof(dumpdevname));
if (wantcopy >= sizeof(dumpdevname)) {
printf("set_dumper: device name truncated from '%s' -> '%s'\n",
devname, dumpdevname);
}
return (0);
}
/* Call dumper with bounds checking. */
int
dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical,
off_t offset, size_t length)
{
if (length != 0 && (offset < di->mediaoffset ||
offset - di->mediaoffset + length > di->mediasize)) {
printf("Attempt to write outside dump device boundaries.\n"
"offset(%jd), mediaoffset(%jd), length(%ju), mediasize(%jd).\n",
(intmax_t)offset, (intmax_t)di->mediaoffset,
(uintmax_t)length, (intmax_t)di->mediasize);
return (ENOSPC);
}
return (di->dumper(di->priv, virtual, physical, offset, length));
}
void
mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver,
uint64_t dumplen, uint32_t blksz)
{
bzero(kdh, sizeof(*kdh));
strncpy(kdh->magic, magic, sizeof(kdh->magic));
strncpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture));
kdh->version = htod32(KERNELDUMPVERSION);
kdh->architectureversion = htod32(archver);
kdh->dumplength = htod64(dumplen);
kdh->dumptime = htod64(time_second);
kdh->blocksize = htod32(blksz);
strncpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname));
strncpy(kdh->versionstring, version, sizeof(kdh->versionstring));
if (panicstr != NULL)
strncpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring));
kdh->parity = kerneldump_parity(kdh);
}