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libvirt/src/util/virprocess.c
Andrea Bolognani 868d043a09 process: Translate "unlimited" correctly 
The value we use internally to represent the lack of a memory
locking limit, VIR_DOMAIN_MEMORY_PARAM_UNLIMITED, doesn't
match the value setrlimit() and prlimit() use for the same
purpose, RLIM_INFINITY, so we have to handle the translation
ourselves.

Partially-resolves: https://bugzilla.redhat.com/1431793
2017-03-28 10:54:49 +02:00

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/*
* virprocess.c: interaction with processes
*
* Copyright (C) 2010-2015 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*
*/
#include <config.h>
#include <fcntl.h>
#include <signal.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <unistd.h>
#if HAVE_SYS_MOUNT_H
# include <sys/mount.h>
#endif
#if HAVE_SETRLIMIT
# include <sys/time.h>
# include <sys/resource.h>
#endif
#if HAVE_SCHED_SETSCHEDULER
# include <sched.h>
#endif
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || HAVE_BSD_CPU_AFFINITY
# include <sys/param.h>
#endif
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
# include <sys/sysctl.h>
# include <sys/user.h>
#endif
#if HAVE_BSD_CPU_AFFINITY
# include <sys/cpuset.h>
#endif
#include "viratomic.h"
#include "virprocess.h"
#include "virerror.h"
#include "viralloc.h"
#include "virfile.h"
#include "virlog.h"
#include "virutil.h"
#include "virstring.h"
#include "vircommand.h"
#define VIR_FROM_THIS VIR_FROM_NONE
VIR_LOG_INIT("util.process");
#ifdef __linux__
/*
* Workaround older glibc. While kernel may support the setns
* syscall, the glibc wrapper might not exist. If that's the
* case, use our own.
*/
# ifndef __NR_setns
# if defined(__x86_64__)
# define __NR_setns 308
# elif defined(__i386__)
# define __NR_setns 346
# elif defined(__arm__)
# define __NR_setns 375
# elif defined(__aarch64__)
# define __NR_setns 375
# elif defined(__powerpc__)
# define __NR_setns 350
# elif defined(__s390__)
# define __NR_setns 339
# endif
# endif
# ifndef HAVE_SETNS
# if defined(__NR_setns)
# include <sys/syscall.h>
static inline int setns(int fd, int nstype)
{
return syscall(__NR_setns, fd, nstype);
}
# else /* !__NR_setns */
# error Please determine the syscall number for setns on your architecture
# endif
# endif
#else /* !__linux__ */
static inline int setns(int fd ATTRIBUTE_UNUSED, int nstype ATTRIBUTE_UNUSED)
{
virReportSystemError(ENOSYS, "%s",
_("Namespaces are not supported on this platform."));
return -1;
}
#endif
VIR_ENUM_IMPL(virProcessSchedPolicy, VIR_PROC_POLICY_LAST,
"none",
"batch",
"idle",
"fifo",
"rr");
/**
* virProcessTranslateStatus:
* @status: child exit status to translate
*
* Translate an exit status into a malloc'd string. Generic helper
* for virCommandRun(), virCommandWait(), virRun(), and virProcessWait()
* status argument, as well as raw waitpid().
*/
char *
virProcessTranslateStatus(int status)
{
char *buf;
if (WIFEXITED(status)) {
ignore_value(virAsprintfQuiet(&buf, _("exit status %d"),
WEXITSTATUS(status)));
} else if (WIFSIGNALED(status)) {
ignore_value(virAsprintfQuiet(&buf, _("fatal signal %d"),
WTERMSIG(status)));
} else {
ignore_value(virAsprintfQuiet(&buf, _("invalid value %d"), status));
}
return buf;
}
#ifndef WIN32
/**
* virProcessAbort:
* @pid: child process to kill
*
* Abort a child process if PID is positive and that child is still
* running, without issuing any errors or affecting errno. Designed
* for error paths where some but not all paths to the cleanup code
* might have started the child process. If @pid is 0 or negative,
* this does nothing.
*/
void
virProcessAbort(pid_t pid)
{
int saved_errno;
int ret;
int status;
char *tmp = NULL;
if (pid <= 0)
return;
/* See if intermediate process has exited; if not, try a nice
* SIGTERM followed by a more severe SIGKILL.
*/
saved_errno = errno;
VIR_DEBUG("aborting child process %d", pid);
while ((ret = waitpid(pid, &status, WNOHANG)) == -1 &&
errno == EINTR);
if (ret == pid) {
tmp = virProcessTranslateStatus(status);
VIR_DEBUG("process has ended: %s", tmp);
goto cleanup;
} else if (ret == 0) {
VIR_DEBUG("trying SIGTERM to child process %d", pid);
kill(pid, SIGTERM);
usleep(10 * 1000);
while ((ret = waitpid(pid, &status, WNOHANG)) == -1 &&
errno == EINTR);
if (ret == pid) {
tmp = virProcessTranslateStatus(status);
VIR_DEBUG("process has ended: %s", tmp);
goto cleanup;
} else if (ret == 0) {
VIR_DEBUG("trying SIGKILL to child process %d", pid);
kill(pid, SIGKILL);
while ((ret = waitpid(pid, &status, 0)) == -1 &&
errno == EINTR);
if (ret == pid) {
tmp = virProcessTranslateStatus(status);
VIR_DEBUG("process has ended: %s", tmp);
goto cleanup;
}
}
}
VIR_DEBUG("failed to reap child %lld, abandoning it", (long long) pid);
cleanup:
VIR_FREE(tmp);
errno = saved_errno;
}
#else
void
virProcessAbort(pid_t pid)
{
/* Not yet ported to mingw. Any volunteers? */
VIR_DEBUG("failed to reap child %lld, abandoning it", (long long)pid);
}
#endif
/**
* virProcessWait:
* @pid: child to wait on
* @exitstatus: optional status collection
* @raw: whether to pass non-normal status back to caller
*
* Wait for a child process to complete. If @pid is -1, do nothing, but
* return -1 (useful for error cleanup, and assumes an earlier message was
* already issued). All other pids issue an error message on failure.
*
* If @exitstatus is NULL, then the child must exit normally with status 0.
* Otherwise, if @raw is false, the child must exit normally, and
* @exitstatus will contain the final exit status (no need for the caller
* to use WEXITSTATUS()). If @raw is true, then the result of waitpid() is
* returned in @exitstatus, and the caller must use WIFEXITED() and friends
* to decipher the child's status.
*
* Returns 0 on a successful wait. Returns -1 on any error waiting for
* completion, or if the command completed with a status that cannot be
* reflected via the choice of @exitstatus and @raw.
*/
int
virProcessWait(pid_t pid, int *exitstatus, bool raw)
{
int ret;
int status;
if (pid <= 0) {
if (pid != -1)
virReportSystemError(EINVAL, _("unable to wait for process %lld"),
(long long) pid);
return -1;
}
/* Wait for intermediate process to exit */
while ((ret = waitpid(pid, &status, 0)) == -1 &&
errno == EINTR);
if (ret == -1) {
virReportSystemError(errno, _("unable to wait for process %lld"),
(long long) pid);
return -1;
}
if (exitstatus == NULL) {
if (status != 0)
goto error;
} else if (raw) {
*exitstatus = status;
} else if (WIFEXITED(status)) {
*exitstatus = WEXITSTATUS(status);
} else {
goto error;
}
return 0;
error:
{
char *st = virProcessTranslateStatus(status);
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Child process (%lld) unexpected %s"),
(long long) pid, NULLSTR(st));
VIR_FREE(st);
}
return -1;
}
/* send signal to a single process */
int virProcessKill(pid_t pid, int sig)
{
if (pid <= 1) {
errno = ESRCH;
return -1;
}
#ifdef WIN32
/* Mingw / Windows don't have many signals (AFAIK) */
switch (sig) {
case SIGINT:
/* This does a Ctrl+C equiv */
if (!GenerateConsoleCtrlEvent(CTRL_C_EVENT, pid)) {
errno = ESRCH;
return -1;
}
break;
case SIGTERM:
/* Since TerminateProcess is closer to SIG_KILL, we do
* a Ctrl+Break equiv which is more pleasant like the
* good old unix SIGTERM/HUP
*/
if (!GenerateConsoleCtrlEvent(CTRL_BREAK_EVENT, pid)) {
errno = ESRCH;
return -1;
}
break;
default:
{
HANDLE proc;
proc = OpenProcess(PROCESS_TERMINATE, FALSE, pid);
if (!proc) {
errno = ESRCH; /* Not entirely accurate, but close enough */
return -1;
}
/*
* TerminateProcess is more or less equiv to SIG_KILL, in that
* a process can't trap / block it
*/
if (sig != 0 && !TerminateProcess(proc, sig)) {
errno = ESRCH;
return -1;
}
CloseHandle(proc);
}
}
return 0;
#else
return kill(pid, sig);
#endif
}
/*
* Try to kill the process and verify it has exited
*
* Returns 0 if it was killed gracefully, 1 if it
* was killed forcibly, -1 if it is still alive,
* or another error occurred.
*/
int
virProcessKillPainfully(pid_t pid, bool force)
{
size_t i;
int ret = -1;
const char *signame = "TERM";
VIR_DEBUG("vpid=%lld force=%d", (long long)pid, force);
/* This loop sends SIGTERM, then waits a few iterations (10 seconds)
* to see if it dies. If the process still hasn't exited, and
* @force is requested, a SIGKILL will be sent, and this will
* wait up to 5 seconds more for the process to exit before
* returning.
*
* Note that setting @force could result in dataloss for the process.
*/
for (i = 0; i < 75; i++) {
int signum;
if (i == 0) {
signum = SIGTERM; /* kindly suggest it should exit */
} else if (i == 50 && force) {
VIR_DEBUG("Timed out waiting after SIGTERM to process %lld, "
"sending SIGKILL", (long long)pid);
/* No SIGKILL kill on Win32 ! Use SIGABRT instead which our
* virProcessKill proc will handle more or less like SIGKILL */
#ifdef WIN32
signum = SIGABRT; /* kill it after a grace period */
signame = "ABRT";
#else
signum = SIGKILL; /* kill it after a grace period */
signame = "KILL";
#endif
} else {
signum = 0; /* Just check for existence */
}
if (virProcessKill(pid, signum) < 0) {
if (errno != ESRCH) {
virReportSystemError(errno,
_("Failed to terminate process %lld with SIG%s"),
(long long)pid, signame);
goto cleanup;
}
ret = signum == SIGTERM ? 0 : 1;
goto cleanup; /* process is dead */
}
usleep(200 * 1000);
}
virReportSystemError(EBUSY,
_("Failed to terminate process %lld with SIG%s"),
(long long)pid, signame);
cleanup:
return ret;
}
#if HAVE_SCHED_GETAFFINITY
int virProcessSetAffinity(pid_t pid, virBitmapPtr map)
{
size_t i;
VIR_DEBUG("Set process affinity on %lld", (long long)pid);
# ifdef CPU_ALLOC
/* New method dynamically allocates cpu mask, allowing unlimted cpus */
int numcpus = 1024;
size_t masklen;
cpu_set_t *mask;
/* Not only may the statically allocated cpu_set_t be too small,
* but there is no way to ask the kernel what size is large enough.
* So you have no option but to pick a size, try, catch EINVAL,
* enlarge, and re-try.
*
* http://lkml.org/lkml/2009/7/28/620
*/
realloc:
masklen = CPU_ALLOC_SIZE(numcpus);
mask = CPU_ALLOC(numcpus);
if (!mask) {
virReportOOMError();
return -1;
}
CPU_ZERO_S(masklen, mask);
for (i = 0; i < virBitmapSize(map); i++) {
if (virBitmapIsBitSet(map, i))
CPU_SET_S(i, masklen, mask);
}
if (sched_setaffinity(pid, masklen, mask) < 0) {
CPU_FREE(mask);
if (errno == EINVAL &&
numcpus < (1024 << 8)) { /* 262144 cpus ought to be enough for anyone */
numcpus = numcpus << 2;
goto realloc;
}
virReportSystemError(errno,
_("cannot set CPU affinity on process %d"), pid);
return -1;
}
CPU_FREE(mask);
# else
/* Legacy method uses a fixed size cpu mask, only allows up to 1024 cpus */
cpu_set_t mask;
CPU_ZERO(&mask);
for (i = 0; i < virBitmapSize(map); i++) {
if (virBitmapIsBitSet(map, i))
CPU_SET(i, &mask);
}
if (sched_setaffinity(pid, sizeof(mask), &mask) < 0) {
virReportSystemError(errno,
_("cannot set CPU affinity on process %d"), pid);
return -1;
}
# endif
return 0;
}
virBitmapPtr
virProcessGetAffinity(pid_t pid)
{
size_t i;
cpu_set_t *mask;
size_t masklen;
size_t ncpus;
virBitmapPtr ret = NULL;
# ifdef CPU_ALLOC
/* 262144 cpus ought to be enough for anyone */
ncpus = 1024 << 8;
masklen = CPU_ALLOC_SIZE(ncpus);
mask = CPU_ALLOC(ncpus);
if (!mask) {
virReportOOMError();
return NULL;
}
CPU_ZERO_S(masklen, mask);
# else
ncpus = 1024;
if (VIR_ALLOC(mask) < 0)
return NULL;
masklen = sizeof(*mask);
CPU_ZERO(mask);
# endif
if (sched_getaffinity(pid, masklen, mask) < 0) {
virReportSystemError(errno,
_("cannot get CPU affinity of process %d"), pid);
goto cleanup;
}
if (!(ret = virBitmapNew(ncpus)))
goto cleanup;
for (i = 0; i < ncpus; i++) {
# ifdef CPU_ALLOC
/* coverity[overrun-local] */
if (CPU_ISSET_S(i, masklen, mask))
ignore_value(virBitmapSetBit(ret, i));
# else
if (CPU_ISSET(i, mask))
ignore_value(virBitmapSetBit(ret, i));
# endif
}
cleanup:
# ifdef CPU_ALLOC
CPU_FREE(mask);
# else
VIR_FREE(mask);
# endif
return ret;
}
#elif defined(HAVE_BSD_CPU_AFFINITY)
int virProcessSetAffinity(pid_t pid,
virBitmapPtr map)
{
size_t i;
cpuset_t mask;
CPU_ZERO(&mask);
for (i = 0; i < virBitmapSize(map); i++) {
if (virBitmapIsBitSet(map, i))
CPU_SET(i, &mask);
}
if (cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_PID, pid,
sizeof(mask), &mask) != 0) {
virReportSystemError(errno,
_("cannot set CPU affinity on process %d"), pid);
return -1;
}
return 0;
}
virBitmapPtr
virProcessGetAffinity(pid_t pid)
{
size_t i;
cpuset_t mask;
virBitmapPtr ret = NULL;
CPU_ZERO(&mask);
if (cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_PID, pid,
sizeof(mask), &mask) != 0) {
virReportSystemError(errno,
_("cannot get CPU affinity of process %d"), pid);
return NULL;
}
if (!(ret = virBitmapNew(sizeof(mask) * 8)))
return NULL;
for (i = 0; i < sizeof(mask) * 8; i++)
if (CPU_ISSET(i, &mask))
ignore_value(virBitmapSetBit(ret, i));
return ret;
}
#else /* HAVE_SCHED_GETAFFINITY */
int virProcessSetAffinity(pid_t pid ATTRIBUTE_UNUSED,
virBitmapPtr map ATTRIBUTE_UNUSED)
{
virReportSystemError(ENOSYS, "%s",
_("Process CPU affinity is not supported on this platform"));
return -1;
}
virBitmapPtr
virProcessGetAffinity(pid_t pid ATTRIBUTE_UNUSED)
{
virReportSystemError(ENOSYS, "%s",
_("Process CPU affinity is not supported on this platform"));
return NULL;
}
#endif /* HAVE_SCHED_GETAFFINITY */
int virProcessGetPids(pid_t pid, size_t *npids, pid_t **pids)
{
int ret = -1;
char *taskPath = NULL;
DIR *dir = NULL;
int value;
struct dirent *ent;
*npids = 0;
*pids = NULL;
if (virAsprintf(&taskPath, "/proc/%llu/task", (long long) pid) < 0)
goto cleanup;
if (virDirOpen(&dir, taskPath) < 0)
goto cleanup;
while ((value = virDirRead(dir, &ent, taskPath)) > 0) {
long long tmp;
pid_t tmp_pid;
if (virStrToLong_ll(ent->d_name, NULL, 10, &tmp) < 0)
goto cleanup;
tmp_pid = tmp;
if (VIR_APPEND_ELEMENT(*pids, *npids, tmp_pid) < 0)
goto cleanup;
}
if (value < 0)
goto cleanup;
ret = 0;
cleanup:
VIR_DIR_CLOSE(dir);
VIR_FREE(taskPath);
if (ret < 0)
VIR_FREE(*pids);
return ret;
}
int virProcessGetNamespaces(pid_t pid,
size_t *nfdlist,
int **fdlist)
{
int ret = -1;
char *nsfile = NULL;
size_t i = 0;
const char *ns[] = { "user", "ipc", "uts", "net", "pid", "mnt" };
*nfdlist = 0;
*fdlist = NULL;
for (i = 0; i < ARRAY_CARDINALITY(ns); i++) {
int fd;
if (virAsprintf(&nsfile, "/proc/%llu/ns/%s",
(long long) pid,
ns[i]) < 0)
goto cleanup;
if ((fd = open(nsfile, O_RDONLY)) >= 0) {
if (VIR_EXPAND_N(*fdlist, *nfdlist, 1) < 0) {
VIR_FORCE_CLOSE(fd);
goto cleanup;
}
(*fdlist)[(*nfdlist)-1] = fd;
}
VIR_FREE(nsfile);
}
ret = 0;
cleanup:
VIR_FREE(nsfile);
if (ret < 0) {
for (i = 0; i < *nfdlist; i++)
VIR_FORCE_CLOSE((*fdlist)[i]);
VIR_FREE(*fdlist);
}
return ret;
}
int virProcessSetNamespaces(size_t nfdlist,
int *fdlist)
{
size_t i;
if (nfdlist == 0) {
virReportInvalidArg(nfdlist, "%s",
_("Expected at least one file descriptor"));
return -1;
}
for (i = 0; i < nfdlist; i++) {
if (fdlist[i] < 0)
continue;
/* We get EINVAL if new NS is same as the current
* NS, or if the fd namespace doesn't match the
* type passed to setns()'s second param. Since we
* pass 0, we know the EINVAL is harmless
*/
if (setns(fdlist[i], 0) < 0 &&
errno != EINVAL) {
virReportSystemError(errno, "%s",
_("Unable to join domain namespace"));
return -1;
}
}
return 0;
}
#if HAVE_PRLIMIT
static int
virProcessPrLimit(pid_t pid,
int resource,
const struct rlimit *new_limit,
struct rlimit *old_limit)
{
return prlimit(pid, resource, new_limit, old_limit);
}
#elif HAVE_SETRLIMIT
static int
virProcessPrLimit(pid_t pid ATTRIBUTE_UNUSED,
int resource ATTRIBUTE_UNUSED,
const struct rlimit *new_limit ATTRIBUTE_UNUSED,
struct rlimit *old_limit ATTRIBUTE_UNUSED)
{
errno = ENOSYS;
return -1;
}
#endif
#if HAVE_SETRLIMIT && defined(RLIMIT_MEMLOCK)
int
virProcessSetMaxMemLock(pid_t pid, unsigned long long bytes)
{
struct rlimit rlim;
if (bytes == 0)
return 0;
/* We use VIR_DOMAIN_MEMORY_PARAM_UNLIMITED internally to represent
* unlimited memory amounts, but setrlimit() and prlimit() use
* RLIM_INFINITY for the same purpose, so we need to translate between
* the two conventions */
if (virMemoryLimitIsSet(bytes))
rlim.rlim_cur = rlim.rlim_max = bytes;
else
rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
if (pid == 0) {
if (setrlimit(RLIMIT_MEMLOCK, &rlim) < 0) {
virReportSystemError(errno,
_("cannot limit locked memory to %llu"),
bytes);
return -1;
}
} else {
if (virProcessPrLimit(pid, RLIMIT_MEMLOCK, &rlim, NULL) < 0) {
virReportSystemError(errno,
_("cannot limit locked memory "
"of process %lld to %llu"),
(long long int)pid, bytes);
return -1;
}
}
VIR_DEBUG("Locked memory for process %lld limited to %llu bytes",
(long long int) pid, bytes);
return 0;
}
#else /* ! (HAVE_SETRLIMIT && defined(RLIMIT_MEMLOCK)) */
int
virProcessSetMaxMemLock(pid_t pid ATTRIBUTE_UNUSED, unsigned long long bytes)
{
if (bytes == 0)
return 0;
virReportSystemError(ENOSYS, "%s", _("Not supported on this platform"));
return -1;
}
#endif /* ! (HAVE_SETRLIMIT && defined(RLIMIT_MEMLOCK)) */
#if HAVE_GETRLIMIT && defined(RLIMIT_MEMLOCK)
int
virProcessGetMaxMemLock(pid_t pid,
unsigned long long *bytes)
{
struct rlimit rlim;
if (!bytes)
return 0;
if (pid == 0) {
if (getrlimit(RLIMIT_MEMLOCK, &rlim) < 0) {
virReportSystemError(errno,
"%s",
_("cannot get locked memory limit"));
return -1;
}
} else {
if (virProcessPrLimit(pid, RLIMIT_MEMLOCK, NULL, &rlim) < 0) {
virReportSystemError(errno,
_("cannot get locked memory limit "
"of process %lld"),
(long long int) pid);
return -1;
}
}
/* virProcessSetMaxMemLock() sets both rlim_cur and rlim_max to the
* same value, so we can retrieve just rlim_max here. We use
* VIR_DOMAIN_MEMORY_PARAM_UNLIMITED internally to represent unlimited
* memory amounts, but setrlimit() and prlimit() use RLIM_INFINITY for the
* same purpose, so we need to translate between the two conventions */
if (rlim.rlim_max == RLIM_INFINITY)
*bytes = VIR_DOMAIN_MEMORY_PARAM_UNLIMITED;
else
*bytes = rlim.rlim_max;
return 0;
}
#else /* ! (HAVE_GETRLIMIT && defined(RLIMIT_MEMLOCK)) */
int
virProcessGetMaxMemLock(pid_t pid ATTRIBUTE_UNUSED,
unsigned long long *bytes)
{
if (!bytes)
return 0;
virReportSystemError(ENOSYS, "%s", _("Not supported on this platform"));
return -1;
}
#endif /* ! (HAVE_GETRLIMIT && defined(RLIMIT_MEMLOCK)) */
#if HAVE_SETRLIMIT && defined(RLIMIT_NPROC)
int
virProcessSetMaxProcesses(pid_t pid, unsigned int procs)
{
struct rlimit rlim;
if (procs == 0)
return 0;
rlim.rlim_cur = rlim.rlim_max = procs;
if (pid == 0) {
if (setrlimit(RLIMIT_NPROC, &rlim) < 0) {
virReportSystemError(errno,
_("cannot limit number of subprocesses to %u"),
procs);
return -1;
}
} else {
if (virProcessPrLimit(pid, RLIMIT_NPROC, &rlim, NULL) < 0) {
virReportSystemError(errno,
_("cannot limit number of subprocesses "
"of process %lld to %u"),
(long long int)pid, procs);
return -1;
}
}
return 0;
}
#else /* ! (HAVE_SETRLIMIT && defined(RLIMIT_NPROC)) */
int
virProcessSetMaxProcesses(pid_t pid ATTRIBUTE_UNUSED, unsigned int procs)
{
if (procs == 0)
return 0;
virReportSystemError(ENOSYS, "%s", _("Not supported on this platform"));
return -1;
}
#endif /* ! (HAVE_SETRLIMIT && defined(RLIMIT_NPROC)) */
#if HAVE_SETRLIMIT && defined(RLIMIT_NOFILE)
int
virProcessSetMaxFiles(pid_t pid, unsigned int files)
{
struct rlimit rlim;
if (files == 0)
return 0;
/* Max number of opened files is one greater than actual limit. See
* man setrlimit.
*
* NB: That indicates to me that we would want the following code
* to say "files - 1", but the original of this code in
* qemu_process.c also had files + 1, so this preserves current
* behavior.
*/
rlim.rlim_cur = rlim.rlim_max = files + 1;
if (pid == 0) {
if (setrlimit(RLIMIT_NOFILE, &rlim) < 0) {
virReportSystemError(errno,
_("cannot limit number of open files to %u"),
files);
return -1;
}
} else {
if (virProcessPrLimit(pid, RLIMIT_NOFILE, &rlim, NULL) < 0) {
virReportSystemError(errno,
_("cannot limit number of open files "
"of process %lld to %u"),
(long long int)pid, files);
return -1;
}
}
return 0;
}
#else /* ! (HAVE_SETRLIMIT && defined(RLIMIT_NOFILE)) */
int
virProcessSetMaxFiles(pid_t pid ATTRIBUTE_UNUSED, unsigned int files)
{
if (files == 0)
return 0;
virReportSystemError(ENOSYS, "%s", _("Not supported on this platform"));
return -1;
}
#endif /* ! (HAVE_SETRLIMIT && defined(RLIMIT_NOFILE)) */
#if HAVE_SETRLIMIT && defined(RLIMIT_CORE)
int
virProcessSetMaxCoreSize(pid_t pid, unsigned long long bytes)
{
struct rlimit rlim;
rlim.rlim_cur = rlim.rlim_max = bytes;
if (pid == 0) {
if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
virReportSystemError(errno,
_("cannot limit core file size to %llu"),
bytes);
return -1;
}
} else {
if (virProcessPrLimit(pid, RLIMIT_CORE, &rlim, NULL) < 0) {
virReportSystemError(errno,
_("cannot limit core file size "
"of process %lld to %llu"),
(long long int)pid, bytes);
return -1;
}
}
return 0;
}
#else /* ! (HAVE_SETRLIMIT && defined(RLIMIT_CORE)) */
int
virProcessSetMaxCoreSize(pid_t pid ATTRIBUTE_UNUSED,
unsigned long long bytes)
{
if (bytes == 0)
return 0;
virReportSystemError(ENOSYS, "%s", _("Not supported on this platform"));
return -1;
}
#endif /* ! (HAVE_SETRLIMIT && defined(RLIMIT_CORE)) */
#ifdef __linux__
/*
* Port of code from polkitunixprocess.c under terms
* of the LGPLv2+
*/
int virProcessGetStartTime(pid_t pid,
unsigned long long *timestamp)
{
char *filename = NULL;
char *buf = NULL;
char *tmp;
int ret = -1;
int len;
char **tokens = NULL;
if (virAsprintf(&filename, "/proc/%llu/stat", (long long) pid) < 0)
return -1;
if ((len = virFileReadAll(filename, 1024, &buf)) < 0)
goto cleanup;
/* start time is the token at index 19 after the '(process name)' entry - since only this
* field can contain the ')' character, search backwards for this to avoid malicious
* processes trying to fool us
*/
if (!(tmp = strrchr(buf, ')'))) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Cannot find start time in %s"),
filename);
goto cleanup;
}
tmp += 2; /* skip ') ' */
if ((tmp - buf) >= len) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Cannot find start time in %s"),
filename);
goto cleanup;
}
tokens = virStringSplit(tmp, " ", 0);
if (virStringListLength((const char * const *)tokens) < 20) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Cannot find start time in %s"),
filename);
goto cleanup;
}
if (virStrToLong_ull(tokens[19],
NULL,
10,
timestamp) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Cannot parse start time %s in %s"),
tokens[19], filename);
goto cleanup;
}
ret = 0;
cleanup:
virStringListFree(tokens);
VIR_FREE(filename);
VIR_FREE(buf);
return ret;
}
#elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
int virProcessGetStartTime(pid_t pid,
unsigned long long *timestamp)
{
struct kinfo_proc p;
int mib[4];
size_t len = 4;
sysctlnametomib("kern.proc.pid", mib, &len);
len = sizeof(struct kinfo_proc);
mib[3] = pid;
if (sysctl(mib, 4, &p, &len, NULL, 0) < 0) {
virReportSystemError(errno, "%s",
_("Unable to query process ID start time"));
return -1;
}
*timestamp = (unsigned long long)p.ki_start.tv_sec;
return 0;
}
#else
int virProcessGetStartTime(pid_t pid,
unsigned long long *timestamp)
{
static int warned;
if (virAtomicIntInc(&warned) == 1) {
VIR_WARN("Process start time of pid %lld not available on this platform",
(long long) pid);
}
*timestamp = 0;
return 0;
}
#endif
static int virProcessNamespaceHelper(int errfd,
pid_t pid,
virProcessNamespaceCallback cb,
void *opaque)
{
char *path;
int fd = -1;
int ret = -1;
if (virAsprintf(&path, "/proc/%lld/ns/mnt", (long long) pid) < 0)
goto cleanup;
if ((fd = open(path, O_RDONLY)) < 0) {
virReportSystemError(errno, "%s",
_("Kernel does not provide mount namespace"));
goto cleanup;
}
if (setns(fd, 0) < 0) {
virReportSystemError(errno, "%s",
_("Unable to enter mount namespace"));
goto cleanup;
}
ret = cb(pid, opaque);
cleanup:
if (ret < 0) {
virErrorPtr err = virGetLastError();
if (err) {
size_t len = strlen(err->message) + 1;
ignore_value(safewrite(errfd, err->message, len));
}
}
VIR_FREE(path);
VIR_FORCE_CLOSE(fd);
return ret;
}
/* Run cb(opaque) in the mount namespace of pid. Return -1 with error
* message raised if we fail to run the child, if the child dies from
* a signal, or if the child has status EXIT_CANCELED; otherwise return
* the exit status of the child. The callback will be run in a child
* process so must be careful to only use async signal safe functions.
*/
int
virProcessRunInMountNamespace(pid_t pid,
virProcessNamespaceCallback cb,
void *opaque)
{
int ret = -1;
pid_t child = -1;
int errfd[2] = { -1, -1 };
if (pipe2(errfd, O_CLOEXEC) < 0) {
virReportSystemError(errno, "%s",
_("Cannot create pipe for child"));
return -1;
}
if ((child = virFork()) < 0)
goto cleanup;
if (child == 0) {
VIR_FORCE_CLOSE(errfd[0]);
ret = virProcessNamespaceHelper(errfd[1], pid,
cb, opaque);
VIR_FORCE_CLOSE(errfd[1]);
_exit(ret < 0 ? EXIT_CANCELED : ret);
} else {
char *buf = NULL;
int status;
VIR_FORCE_CLOSE(errfd[1]);
ignore_value(virFileReadHeaderFD(errfd[0], 1024, &buf));
ret = virProcessWait(child, &status, false);
if (!ret) {
ret = status == EXIT_CANCELED ? -1 : status;
if (ret) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("child reported: %s"),
NULLSTR(buf));
}
}
VIR_FREE(buf);
}
cleanup:
VIR_FORCE_CLOSE(errfd[0]);
VIR_FORCE_CLOSE(errfd[1]);
return ret;
}
#if defined(HAVE_SYS_MOUNT_H) && defined(HAVE_UNSHARE)
int
virProcessSetupPrivateMountNS(void)
{
int ret = -1;
if (unshare(CLONE_NEWNS) < 0) {
virReportSystemError(errno, "%s",
_("Cannot unshare mount namespace"));
goto cleanup;
}
if (mount("", "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) {
virReportSystemError(errno, "%s",
_("Failed to switch root mount into slave mode"));
goto cleanup;
}
ret = 0;
cleanup:
return ret;
}
#else /* !defined(HAVE_SYS_MOUNT_H) || !defined(HAVE_UNSHARE) */
int
virProcessSetupPrivateMountNS(void)
{
virReportSystemError(ENOSYS, "%s",
_("Namespaces are not supported on this platform."));
return -1;
}
#endif /* !defined(HAVE_SYS_MOUNT_H) || !defined(HAVE_UNSHARE) */
#if defined(__linux__)
ATTRIBUTE_NORETURN static int
virProcessDummyChild(void *argv ATTRIBUTE_UNUSED)
{
_exit(0);
}
/**
* virProcessNamespaceAvailable:
* @ns: what namespaces to check (bitwise-OR of virProcessNamespaceFlags)
*
* Check if given list of namespaces (@ns) is available.
* If not, appropriate error message is produced.
*
* Returns: 0 on success (all the namespaces from @flags are available),
* -1 on error (with error message reported).
*/
int
virProcessNamespaceAvailable(unsigned int ns)
{
int flags = 0;
int cpid;
char *childStack;
char *stack;
int stacksize = getpagesize() * 4;
if (ns & VIR_PROCESS_NAMESPACE_MNT)
flags |= CLONE_NEWNS;
if (ns & VIR_PROCESS_NAMESPACE_IPC)
flags |= CLONE_NEWIPC;
if (ns & VIR_PROCESS_NAMESPACE_NET)
flags |= CLONE_NEWNET;
if (ns & VIR_PROCESS_NAMESPACE_PID)
flags |= CLONE_NEWPID;
if (ns & VIR_PROCESS_NAMESPACE_USER)
flags |= CLONE_NEWUSER;
if (ns & VIR_PROCESS_NAMESPACE_UTS)
flags |= CLONE_NEWUTS;
/* Signal parent as soon as the child dies. RIP. */
flags |= SIGCHLD;
if (VIR_ALLOC_N(stack, stacksize) < 0)
return -1;
childStack = stack + stacksize;
cpid = clone(virProcessDummyChild, childStack, flags, NULL);
VIR_FREE(stack);
if (cpid < 0) {
char ebuf[1024] ATTRIBUTE_UNUSED;
VIR_DEBUG("clone call returned %s, container support is not enabled",
virStrerror(errno, ebuf, sizeof(ebuf)));
return -1;
} else if (virProcessWait(cpid, NULL, false) < 0) {
return -1;
}
VIR_DEBUG("All namespaces (%x) are enabled", ns);
return 0;
}
#else /* !defined(__linux__) */
int
virProcessNamespaceAvailable(unsigned int ns ATTRIBUTE_UNUSED)
{
virReportSystemError(ENOSYS, "%s",
_("Namespaces are not supported on this platform."));
return -1;
}
#endif /* !defined(__linux__) */
/**
* virProcessExitWithStatus:
* @status: raw status to be reproduced when this process dies
*
* Given a raw status obtained by waitpid() or similar, attempt to
* make this process exit in the same manner. If the child died by
* signal, reset that signal handler to default and raise the same
* signal; if that doesn't kill this process, then exit with 128 +
* signal number. If @status can't be deciphered, use
* EXIT_CANNOT_INVOKE.
*
* Never returns.
*/
void
virProcessExitWithStatus(int status)
{
int value = EXIT_CANNOT_INVOKE;
if (WIFEXITED(status)) {
value = WEXITSTATUS(status);
} else if (WIFSIGNALED(status)) {
struct sigaction act;
sigset_t sigs;
if (sigemptyset(&sigs) == 0 &&
sigaddset(&sigs, WTERMSIG(status)) == 0)
sigprocmask(SIG_UNBLOCK, &sigs, NULL);
memset(&act, 0, sizeof(act));
act.sa_handler = SIG_DFL;
sigfillset(&act.sa_mask);
sigaction(WTERMSIG(status), &act, NULL);
raise(WTERMSIG(status));
value = 128 + WTERMSIG(status);
}
exit(value);
}
#if HAVE_SCHED_SETSCHEDULER
static int
virProcessSchedTranslatePolicy(virProcessSchedPolicy policy)
{
switch (policy) {
case VIR_PROC_POLICY_NONE:
return SCHED_OTHER;
case VIR_PROC_POLICY_BATCH:
# ifdef SCHED_BATCH
return SCHED_BATCH;
# else
return -1;
# endif
case VIR_PROC_POLICY_IDLE:
# ifdef SCHED_IDLE
return SCHED_IDLE;
# else
return -1;
# endif
case VIR_PROC_POLICY_FIFO:
return SCHED_FIFO;
case VIR_PROC_POLICY_RR:
return SCHED_RR;
case VIR_PROC_POLICY_LAST:
/* nada */
break;
}
return -1;
}
int
virProcessSetScheduler(pid_t pid,
virProcessSchedPolicy policy,
int priority)
{
struct sched_param param = {0};
int pol = virProcessSchedTranslatePolicy(policy);
VIR_DEBUG("pid=%lld, policy=%d, priority=%u",
(long long) pid, policy, priority);
if (!policy)
return 0;
if (pol < 0) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("Scheduler '%s' is not supported on this platform"),
virProcessSchedPolicyTypeToString(policy));
return -1;
}
if (pol == SCHED_FIFO || pol == SCHED_RR) {
int min = 0;
int max = 0;
if ((min = sched_get_priority_min(pol)) < 0) {
virReportSystemError(errno, "%s",
_("Cannot get minimum scheduler "
"priority value"));
return -1;
}
if ((max = sched_get_priority_max(pol)) < 0) {
virReportSystemError(errno, "%s",
_("Cannot get maximum scheduler "
"priority value"));
return -1;
}
if (priority < min || priority > max) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("Scheduler priority %d out of range [%d, %d]"),
priority, min, max);
return -1;
}
param.sched_priority = priority;
}
if (sched_setscheduler(pid, pol, &param) < 0) {
virReportSystemError(errno,
_("Cannot set scheduler parameters for pid %lld"),
(long long) pid);
return -1;
}
return 0;
}
#else /* ! HAVE_SCHED_SETSCHEDULER */
int
virProcessSetScheduler(pid_t pid ATTRIBUTE_UNUSED,
virProcessSchedPolicy policy,
int priority ATTRIBUTE_UNUSED)
{
if (!policy)
return 0;
virReportSystemError(ENOSYS, "%s",
_("Process CPU scheduling is not supported "
"on this platform"));
return -1;
}
#endif /* !HAVE_SCHED_SETSCHEDULER */
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