freebsd-skq/sys/compat/linux/linux_signal.c
John Polstra 2116e6ab2f Fix a couple of out-of-bounds array references in mapping between
Linux and FreeBSD signal numbers.  Also, check signal numbers passed
in from application programs for validity.  Without these checks,
it is trivial to panic the system from a Linux program.
1998-10-11 04:54:16 +00:00

319 lines
8.5 KiB
C

/*-
* Copyright (c) 1994-1995 Søren Schmidt
* 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
* in this position and unchanged.
* 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. The name of the author may not be used to endorse or promote products
* derived from this software withough specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*
* $Id: linux_signal.c,v 1.12 1998/08/15 22:29:43 bde Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/proc.h>
#include <sys/signalvar.h>
#include <i386/linux/linux.h>
#include <i386/linux/linux_proto.h>
#include <i386/linux/linux_util.h>
static sigset_t
linux_to_bsd_sigset(linux_sigset_t mask) {
int b, l;
sigset_t new = 0;
for (l = 1; l < LINUX_NSIG; l++) {
if (mask & (1 << (l - 1))) {
if ((b = linux_to_bsd_signal[l]))
new |= (1 << (b - 1));
}
}
return new;
}
static linux_sigset_t
bsd_to_linux_sigset(sigset_t mask) {
int b, l;
sigset_t new = 0;
for (b = 1; b < NSIG; b++) {
if (mask & (1 << (b - 1))) {
if ((l = bsd_to_linux_signal[b]))
new |= (1 << (l - 1));
}
}
return new;
}
static void
linux_to_bsd_sigaction(linux_sigaction_t *lsa, struct sigaction *bsa)
{
bsa->sa_mask = linux_to_bsd_sigset(lsa->sa_mask);
bsa->sa_handler = lsa->sa_handler;
bsa->sa_flags = 0;
if (lsa->sa_flags & LINUX_SA_NOCLDSTOP)
bsa->sa_flags |= SA_NOCLDSTOP;
if (lsa->sa_flags & LINUX_SA_ONSTACK)
bsa->sa_flags |= SA_ONSTACK;
if (lsa->sa_flags & LINUX_SA_RESTART)
bsa->sa_flags |= SA_RESTART;
if (lsa->sa_flags & LINUX_SA_ONESHOT)
bsa->sa_flags |= SA_RESETHAND;
if (lsa->sa_flags & LINUX_SA_NOMASK)
bsa->sa_flags |= SA_NODEFER;
}
static void
bsd_to_linux_sigaction(struct sigaction *bsa, linux_sigaction_t *lsa)
{
lsa->sa_handler = bsa->sa_handler;
lsa->sa_restorer = NULL; /* unsupported */
lsa->sa_mask = bsd_to_linux_sigset(bsa->sa_mask);
lsa->sa_flags = 0;
if (bsa->sa_flags & SA_NOCLDSTOP)
lsa->sa_flags |= LINUX_SA_NOCLDSTOP;
if (bsa->sa_flags & SA_ONSTACK)
lsa->sa_flags |= LINUX_SA_ONSTACK;
if (bsa->sa_flags & SA_RESTART)
lsa->sa_flags |= LINUX_SA_RESTART;
if (bsa->sa_flags & SA_RESETHAND)
lsa->sa_flags |= LINUX_SA_ONESHOT;
if (bsa->sa_flags & SA_NODEFER)
lsa->sa_flags |= LINUX_SA_NOMASK;
}
int
linux_sigaction(struct proc *p, struct linux_sigaction_args *args)
{
linux_sigaction_t linux_sa;
struct sigaction *nsa = NULL, *osa = NULL, bsd_sa;
struct sigaction_args sa;
int error;
caddr_t sg = stackgap_init();
#ifdef DEBUG
printf("Linux-emul(%ld): sigaction(%d, %p, %p)\n",
(long)p->p_pid, args->sig, (void *)args->nsa, (void *)args->osa);
#endif
if (args->sig <= 0 || args->sig >= LINUX_NSIG)
return EINVAL;
if (args->osa)
osa = (struct sigaction *)stackgap_alloc(&sg, sizeof(struct sigaction));
if (args->nsa) {
nsa = (struct sigaction *)stackgap_alloc(&sg, sizeof(struct sigaction));
if (error = copyin(args->nsa, &linux_sa, sizeof(linux_sigaction_t)))
return error;
linux_to_bsd_sigaction(&linux_sa, &bsd_sa);
if (error = copyout(&bsd_sa, nsa, sizeof(struct sigaction)))
return error;
}
sa.signum = linux_to_bsd_signal[args->sig];
sa.nsa = nsa;
sa.osa = osa;
if ((error = sigaction(p, &sa)))
return error;
if (args->osa) {
if (error = copyin(osa, &bsd_sa, sizeof(struct sigaction)))
return error;
bsd_to_linux_sigaction(&bsd_sa, &linux_sa);
if (error = copyout(&linux_sa, args->osa, sizeof(linux_sigaction_t)))
return error;
}
return 0;
}
int
linux_signal(struct proc *p, struct linux_signal_args *args)
{
caddr_t sg;
struct sigaction_args sa_args;
struct sigaction *osa, *nsa, tmpsa;
int error;
#ifdef DEBUG
printf("Linux-emul(%ld): signal(%d, %p)\n",
(long)p->p_pid, args->sig, (void *)args->handler);
#endif
if (args->sig <= 0 || args->sig >= LINUX_NSIG)
return EINVAL;
sg = stackgap_init();
nsa = stackgap_alloc(&sg, sizeof *nsa);
osa = stackgap_alloc(&sg, sizeof *osa);
tmpsa.sa_handler = args->handler;
tmpsa.sa_mask = (sigset_t) 0;
tmpsa.sa_flags = SA_RESETHAND | SA_NODEFER;
if ((error = copyout(&tmpsa, nsa, sizeof tmpsa)))
return error;
sa_args.signum = linux_to_bsd_signal[args->sig];
sa_args.osa = osa;
sa_args.nsa = nsa;
if ((error = sigaction(p, &sa_args)))
return error;
if ((error = copyin(osa, &tmpsa, sizeof *osa)))
return error;
p->p_retval[0] = (int)tmpsa.sa_handler;
return 0;
}
int
linux_sigprocmask(struct proc *p, struct linux_sigprocmask_args *args)
{
int error, s;
sigset_t mask;
sigset_t omask;
#ifdef DEBUG
printf("Linux-emul(%d): sigprocmask(%d, *, *)\n", p->p_pid, args->how);
#endif
p->p_retval[0] = 0;
if (args->omask != NULL) {
omask = bsd_to_linux_sigset(p->p_sigmask);
if (error = copyout(&omask, args->omask, sizeof(sigset_t)))
return error;
}
if (!(args->mask))
return 0;
if (error = copyin(args->mask, &mask, sizeof(linux_sigset_t)))
return error;
mask = linux_to_bsd_sigset(mask);
s = splhigh();
switch (args->how) {
case LINUX_SIG_BLOCK:
p->p_sigmask |= (mask & ~sigcantmask);
break;
case LINUX_SIG_UNBLOCK:
p->p_sigmask &= ~mask;
break;
case LINUX_SIG_SETMASK:
p->p_sigmask = (mask & ~sigcantmask);
break;
default:
error = EINVAL;
break;
}
splx(s);
return error;
}
int
linux_siggetmask(struct proc *p, struct linux_siggetmask_args *args)
{
#ifdef DEBUG
printf("Linux-emul(%d): siggetmask()\n", p->p_pid);
#endif
p->p_retval[0] = bsd_to_linux_sigset(p->p_sigmask);
return 0;
}
int
linux_sigsetmask(struct proc *p, struct linux_sigsetmask_args *args)
{
int s;
sigset_t mask;
#ifdef DEBUG
printf("Linux-emul(%ld): sigsetmask(%08lx)\n",
(long)p->p_pid, (unsigned long)args->mask);
#endif
p->p_retval[0] = bsd_to_linux_sigset(p->p_sigmask);
mask = linux_to_bsd_sigset(args->mask);
s = splhigh();
p->p_sigmask = mask & ~sigcantmask;
splx(s);
return 0;
}
int
linux_sigpending(struct proc *p, struct linux_sigpending_args *args)
{
linux_sigset_t linux_sig;
#ifdef DEBUG
printf("Linux-emul(%d): sigpending(*)\n", p->p_pid);
#endif
linux_sig = bsd_to_linux_sigset(p->p_siglist & p->p_sigmask);
return copyout(&linux_sig, args->mask, sizeof(linux_sig));
}
/*
* Linux has two extra args, restart and oldmask. We dont use these,
* but it seems that "restart" is actually a context pointer that
* enables the signal to happen with a different register set.
*/
int
linux_sigsuspend(struct proc *p, struct linux_sigsuspend_args *args)
{
struct sigsuspend_args tmp;
#ifdef DEBUG
printf("Linux-emul(%ld): sigsuspend(%08lx)\n",
(long)p->p_pid, (unsigned long)args->mask);
#endif
tmp.mask = linux_to_bsd_sigset(args->mask);
return sigsuspend(p, &tmp);
}
int
linux_pause(struct proc *p, struct linux_pause_args *args)
{
struct sigsuspend_args tmp;
#ifdef DEBUG
printf("Linux-emul(%d): pause()\n", p->p_pid);
#endif
tmp.mask = p->p_sigmask;
return sigsuspend(p, &tmp);
}
int
linux_kill(struct proc *p, struct linux_kill_args *args)
{
struct kill_args /* {
int pid;
int signum;
} */ tmp;
#ifdef DEBUG
printf("Linux-emul(%d): kill(%d, %d)\n",
p->p_pid, args->pid, args->signum);
#endif
if (args->signum <= 0 || args->signum >= LINUX_NSIG)
return EINVAL;
tmp.pid = args->pid;
tmp.signum = linux_to_bsd_signal[args->signum];
return kill(p, &tmp);
}