freebsd-skq/sys/kern/p1003_1b.c
davidxu 77a76e9949 Don't allow non-root user to set a scheduler policy, otherwise this could
be a local DOS.

Submitted by: Diane Bruce at db at db.net
2006-05-21 00:40:38 +00:00

351 lines
7.7 KiB
C

/*-
* Copyright (c) 1996, 1997, 1998
* HD Associates, Inc. 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by HD Associates, Inc
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY HD ASSOCIATES 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 HD ASSOCIATES 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.
*/
/* p1003_1b: Real Time common code.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_posix.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
#include <sys/sysent.h>
#include <sys/syslog.h>
#include <sys/sysproto.h>
#include <posix4/posix4.h>
MALLOC_DEFINE(M_P31B, "p1003.1b", "Posix 1003.1B");
/* The system calls return ENOSYS if an entry is called that is
* not run-time supported. I am also logging since some programs
* start to use this when they shouldn't. That will be removed if annoying.
*/
int
syscall_not_present(struct thread *td, const char *s, struct nosys_args *uap)
{
log(LOG_ERR, "cmd %s pid %d tried to use non-present %s\n",
td->td_proc->p_comm, td->td_proc->p_pid, s);
/* a " return nosys(p, uap); " here causes a core dump.
*/
return ENOSYS;
}
#if !defined(_KPOSIX_PRIORITY_SCHEDULING)
/* Not configured but loadable via a module:
*/
static int
sched_attach(void)
{
return 0;
}
SYSCALL_NOT_PRESENT_GEN(sched_setparam)
SYSCALL_NOT_PRESENT_GEN(sched_getparam)
SYSCALL_NOT_PRESENT_GEN(sched_setscheduler)
SYSCALL_NOT_PRESENT_GEN(sched_getscheduler)
SYSCALL_NOT_PRESENT_GEN(sched_yield)
SYSCALL_NOT_PRESENT_GEN(sched_get_priority_max)
SYSCALL_NOT_PRESENT_GEN(sched_get_priority_min)
SYSCALL_NOT_PRESENT_GEN(sched_rr_get_interval)
#else
/* Configured in kernel version:
*/
static struct ksched *ksched;
static int
sched_attach(void)
{
int ret = ksched_attach(&ksched);
if (ret == 0)
p31b_setcfg(CTL_P1003_1B_PRIORITY_SCHEDULING, 1);
return ret;
}
/*
* MPSAFE
*/
int
sched_setparam(struct thread *td, struct sched_setparam_args *uap)
{
struct thread *targettd;
struct proc *targetp;
int e;
struct sched_param sched_param;
e = copyin(uap->param, &sched_param, sizeof(sched_param));
if (e)
return (e);
if (uap->pid == 0) {
targetp = td->td_proc;
targettd = td;
PROC_LOCK(targetp);
} else {
targetp = pfind(uap->pid);
if (targetp == NULL) {
e = ESRCH;
goto done2;
}
targettd = FIRST_THREAD_IN_PROC(targetp); /* XXXKSE */
}
e = p_cansched(td, targetp);
if (e == 0) {
e = ksched_setparam(&td->td_retval[0], ksched, targettd,
(const struct sched_param *)&sched_param);
}
PROC_UNLOCK(targetp);
done2:
return (e);
}
/*
* MPSAFE
*/
int
sched_getparam(struct thread *td, struct sched_getparam_args *uap)
{
int e;
struct sched_param sched_param;
struct thread *targettd;
struct proc *targetp;
if (uap->pid == 0) {
targetp = td->td_proc;
targettd = td;
PROC_LOCK(targetp);
} else {
targetp = pfind(uap->pid);
if (targetp == NULL) {
e = ESRCH;
goto done2;
}
targettd = FIRST_THREAD_IN_PROC(targetp); /* XXXKSE */
}
e = p_cansee(td, targetp);
if (e == 0) {
e = ksched_getparam(&td->td_retval[0], ksched, targettd,
&sched_param);
}
PROC_UNLOCK(targetp);
if (e == 0)
e = copyout(&sched_param, uap->param, sizeof(sched_param));
done2:
return (e);
}
/*
* MPSAFE
*/
int
sched_setscheduler(struct thread *td, struct sched_setscheduler_args *uap)
{
int e;
struct sched_param sched_param;
struct thread *targettd;
struct proc *targetp;
/* Don't allow non root user to set a scheduler policy */
if (suser(td) != 0)
return (EPERM);
e = copyin(uap->param, &sched_param, sizeof(sched_param));
if (e)
return (e);
if (uap->pid == 0) {
targetp = td->td_proc;
targettd = td;
PROC_LOCK(targetp);
} else {
targetp = pfind(uap->pid);
if (targetp == NULL) {
e = ESRCH;
goto done2;
}
targettd = FIRST_THREAD_IN_PROC(targetp); /* XXXKSE */
}
e = p_cansched(td, targetp);
if (e == 0) {
e = ksched_setscheduler(&td->td_retval[0], ksched, targettd,
uap->policy, (const struct sched_param *)&sched_param);
}
PROC_UNLOCK(targetp);
done2:
return (e);
}
/*
* MPSAFE
*/
int
sched_getscheduler(struct thread *td, struct sched_getscheduler_args *uap)
{
int e;
struct thread *targettd;
struct proc *targetp;
if (uap->pid == 0) {
targetp = td->td_proc;
targettd = td;
PROC_LOCK(targetp);
} else {
targetp = pfind(uap->pid);
if (targetp == NULL) {
e = ESRCH;
goto done2;
}
targettd = FIRST_THREAD_IN_PROC(targetp); /* XXXKSE */
}
e = p_cansee(td, targetp);
if (e == 0)
e = ksched_getscheduler(&td->td_retval[0], ksched, targettd);
PROC_UNLOCK(targetp);
done2:
return (e);
}
/*
* MPSAFE
*/
int
sched_yield(struct thread *td, struct sched_yield_args *uap)
{
int error;
error = ksched_yield(&td->td_retval[0], ksched);
return (error);
}
/*
* MPSAFE
*/
int
sched_get_priority_max(struct thread *td,
struct sched_get_priority_max_args *uap)
{
int error;
error = ksched_get_priority_max(&td->td_retval[0], ksched, uap->policy);
return (error);
}
/*
* MPSAFE
*/
int
sched_get_priority_min(struct thread *td,
struct sched_get_priority_min_args *uap)
{
int error;
error = ksched_get_priority_min(&td->td_retval[0], ksched, uap->policy);
return (error);
}
/*
* MPSAFE
*/
int
sched_rr_get_interval(struct thread *td,
struct sched_rr_get_interval_args *uap)
{
struct timespec timespec;
int error;
error = kern_sched_rr_get_interval(td, uap->pid, &timespec);
if (error == 0)
error = copyout(&timespec, uap->interval, sizeof(timespec));
return (error);
}
int
kern_sched_rr_get_interval(struct thread *td, pid_t pid,
struct timespec *ts)
{
int e;
struct thread *targettd;
struct proc *targetp;
if (pid == 0) {
targettd = td;
targetp = td->td_proc;
PROC_LOCK(targetp);
} else {
targetp = pfind(pid);
if (targetp == NULL)
return (ESRCH);
targettd = FIRST_THREAD_IN_PROC(targetp); /* XXXKSE */
}
e = p_cansee(td, targetp);
if (e == 0)
e = ksched_rr_get_interval(&td->td_retval[0], ksched, targettd,
ts);
PROC_UNLOCK(targetp);
return (e);
}
#endif
static void
p31binit(void *notused)
{
(void) sched_attach();
p31b_setcfg(CTL_P1003_1B_PAGESIZE, PAGE_SIZE);
}
SYSINIT(p31b, SI_SUB_P1003_1B, SI_ORDER_FIRST, p31binit, NULL);