xref: /freebsd/sys/amd64/ia32/ia32_signal.c (revision d184218c)
1 /*-
2  * Copyright (c) 2003 Peter Wemm
3  * Copyright (c) 1982, 1987, 1990 The Regents of the University of California.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * William Jolitz.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include "opt_compat.h"
38 
39 #include <sys/param.h>
40 #include <sys/exec.h>
41 #include <sys/fcntl.h>
42 #include <sys/imgact.h>
43 #include <sys/kernel.h>
44 #include <sys/lock.h>
45 #include <sys/malloc.h>
46 #include <sys/mutex.h>
47 #include <sys/mman.h>
48 #include <sys/namei.h>
49 #include <sys/pioctl.h>
50 #include <sys/proc.h>
51 #include <sys/procfs.h>
52 #include <sys/resourcevar.h>
53 #include <sys/systm.h>
54 #include <sys/signalvar.h>
55 #include <sys/stat.h>
56 #include <sys/sx.h>
57 #include <sys/syscall.h>
58 #include <sys/syscallsubr.h>
59 #include <sys/sysctl.h>
60 #include <sys/sysent.h>
61 #include <sys/vnode.h>
62 
63 #include <vm/vm.h>
64 #include <vm/vm_kern.h>
65 #include <vm/vm_param.h>
66 #include <vm/pmap.h>
67 #include <vm/vm_map.h>
68 #include <vm/vm_object.h>
69 #include <vm/vm_extern.h>
70 
71 #include <compat/freebsd32/freebsd32_signal.h>
72 #include <compat/freebsd32/freebsd32_util.h>
73 #include <compat/freebsd32/freebsd32_proto.h>
74 #include <compat/freebsd32/freebsd32.h>
75 #include <compat/ia32/ia32_signal.h>
76 #include <machine/psl.h>
77 #include <machine/segments.h>
78 #include <machine/specialreg.h>
79 #include <machine/frame.h>
80 #include <machine/md_var.h>
81 #include <machine/pcb.h>
82 #include <machine/cpufunc.h>
83 
84 #ifdef COMPAT_FREEBSD4
85 static void freebsd4_ia32_sendsig(sig_t, ksiginfo_t *, sigset_t *);
86 #endif
87 
88 #define	CS_SECURE(cs)		(ISPL(cs) == SEL_UPL)
89 #define	EFL_SECURE(ef, oef)	((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
90 
91 static void
92 ia32_get_fpcontext(struct thread *td, struct ia32_mcontext *mcp,
93     char *xfpusave, size_t xfpusave_len)
94 {
95 	size_t max_len, len;
96 
97 	/*
98 	 * XXX Format of 64bit and 32bit FXSAVE areas differs. FXSAVE
99 	 * in 32bit mode saves %cs and %ds, while on 64bit it saves
100 	 * 64bit instruction and data pointers. Ignore the difference
101 	 * for now, it should be irrelevant for most applications.
102 	 */
103 	mcp->mc_ownedfp = fpugetregs(td);
104 	bcopy(get_pcb_user_save_td(td), &mcp->mc_fpstate,
105 	    sizeof(mcp->mc_fpstate));
106 	mcp->mc_fpformat = fpuformat();
107 	if (!use_xsave || xfpusave_len == 0)
108 		return;
109 	max_len = cpu_max_ext_state_size - sizeof(struct savefpu);
110 	len = xfpusave_len;
111 	if (len > max_len) {
112 		len = max_len;
113 		bzero(xfpusave + max_len, len - max_len);
114 	}
115 	mcp->mc_flags |= _MC_HASFPXSTATE;
116 	mcp->mc_xfpustate_len = len;
117 	bcopy(get_pcb_user_save_td(td) + 1, xfpusave, len);
118 }
119 
120 static int
121 ia32_set_fpcontext(struct thread *td, const struct ia32_mcontext *mcp,
122     char *xfpustate, size_t xfpustate_len)
123 {
124 	int error;
125 
126 	if (mcp->mc_fpformat == _MC_FPFMT_NODEV)
127 		return (0);
128 	else if (mcp->mc_fpformat != _MC_FPFMT_XMM)
129 		return (EINVAL);
130 	else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE) {
131 		/* We don't care what state is left in the FPU or PCB. */
132 		fpstate_drop(td);
133 		error = 0;
134 	} else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU ||
135 	    mcp->mc_ownedfp == _MC_FPOWNED_PCB) {
136 		error = fpusetregs(td, (struct savefpu *)&mcp->mc_fpstate,
137 		    xfpustate, xfpustate_len);
138 	} else
139 		return (EINVAL);
140 	return (error);
141 }
142 
143 /*
144  * Get machine context.
145  */
146 static int
147 ia32_get_mcontext(struct thread *td, struct ia32_mcontext *mcp, int flags)
148 {
149 	struct pcb *pcb;
150 	struct trapframe *tp;
151 
152 	pcb = td->td_pcb;
153 	tp = td->td_frame;
154 
155 	PROC_LOCK(curthread->td_proc);
156 	mcp->mc_onstack = sigonstack(tp->tf_rsp);
157 	PROC_UNLOCK(curthread->td_proc);
158 	/* Entry into kernel always sets TF_HASSEGS */
159 	mcp->mc_gs = tp->tf_gs;
160 	mcp->mc_fs = tp->tf_fs;
161 	mcp->mc_es = tp->tf_es;
162 	mcp->mc_ds = tp->tf_ds;
163 	mcp->mc_edi = tp->tf_rdi;
164 	mcp->mc_esi = tp->tf_rsi;
165 	mcp->mc_ebp = tp->tf_rbp;
166 	mcp->mc_isp = tp->tf_rsp;
167 	mcp->mc_eflags = tp->tf_rflags;
168 	if (flags & GET_MC_CLEAR_RET) {
169 		mcp->mc_eax = 0;
170 		mcp->mc_edx = 0;
171 		mcp->mc_eflags &= ~PSL_C;
172 	} else {
173 		mcp->mc_eax = tp->tf_rax;
174 		mcp->mc_edx = tp->tf_rdx;
175 	}
176 	mcp->mc_ebx = tp->tf_rbx;
177 	mcp->mc_ecx = tp->tf_rcx;
178 	mcp->mc_eip = tp->tf_rip;
179 	mcp->mc_cs = tp->tf_cs;
180 	mcp->mc_esp = tp->tf_rsp;
181 	mcp->mc_ss = tp->tf_ss;
182 	mcp->mc_len = sizeof(*mcp);
183 	mcp->mc_flags = tp->tf_flags;
184 	ia32_get_fpcontext(td, mcp, NULL, 0);
185 	mcp->mc_fsbase = pcb->pcb_fsbase;
186 	mcp->mc_gsbase = pcb->pcb_gsbase;
187 	mcp->mc_xfpustate = 0;
188 	mcp->mc_xfpustate_len = 0;
189 	bzero(mcp->mc_spare2, sizeof(mcp->mc_spare2));
190 	set_pcb_flags(pcb, PCB_FULL_IRET);
191 	return (0);
192 }
193 
194 /*
195  * Set machine context.
196  *
197  * However, we don't set any but the user modifiable flags, and we won't
198  * touch the cs selector.
199  */
200 static int
201 ia32_set_mcontext(struct thread *td, const struct ia32_mcontext *mcp)
202 {
203 	struct trapframe *tp;
204 	char *xfpustate;
205 	long rflags;
206 	int ret;
207 
208 	tp = td->td_frame;
209 	if (mcp->mc_len != sizeof(*mcp))
210 		return (EINVAL);
211 	rflags = (mcp->mc_eflags & PSL_USERCHANGE) |
212 	    (tp->tf_rflags & ~PSL_USERCHANGE);
213 	if (mcp->mc_flags & _MC_IA32_HASFPXSTATE) {
214 		if (mcp->mc_xfpustate_len > cpu_max_ext_state_size -
215 		    sizeof(struct savefpu))
216 			return (EINVAL);
217 		xfpustate = __builtin_alloca(mcp->mc_xfpustate_len);
218 		ret = copyin(PTRIN(mcp->mc_xfpustate), xfpustate,
219 		    mcp->mc_xfpustate_len);
220 		if (ret != 0)
221 			return (ret);
222 	} else
223 		xfpustate = NULL;
224 	ret = ia32_set_fpcontext(td, mcp, xfpustate, mcp->mc_xfpustate_len);
225 	if (ret != 0)
226 		return (ret);
227 	tp->tf_gs = mcp->mc_gs;
228 	tp->tf_fs = mcp->mc_fs;
229 	tp->tf_es = mcp->mc_es;
230 	tp->tf_ds = mcp->mc_ds;
231 	tp->tf_flags = TF_HASSEGS;
232 	tp->tf_rdi = mcp->mc_edi;
233 	tp->tf_rsi = mcp->mc_esi;
234 	tp->tf_rbp = mcp->mc_ebp;
235 	tp->tf_rbx = mcp->mc_ebx;
236 	tp->tf_rdx = mcp->mc_edx;
237 	tp->tf_rcx = mcp->mc_ecx;
238 	tp->tf_rax = mcp->mc_eax;
239 	/* trapno, err */
240 	tp->tf_rip = mcp->mc_eip;
241 	tp->tf_rflags = rflags;
242 	tp->tf_rsp = mcp->mc_esp;
243 	tp->tf_ss = mcp->mc_ss;
244 	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
245 	return (0);
246 }
247 
248 /*
249  * The first two fields of a ucontext_t are the signal mask and
250  * the machine context.  The next field is uc_link; we want to
251  * avoid destroying the link when copying out contexts.
252  */
253 #define	UC_COPY_SIZE	offsetof(struct ia32_ucontext, uc_link)
254 
255 int
256 freebsd32_getcontext(struct thread *td, struct freebsd32_getcontext_args *uap)
257 {
258 	struct ia32_ucontext uc;
259 	int ret;
260 
261 	if (uap->ucp == NULL)
262 		ret = EINVAL;
263 	else {
264 		ia32_get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
265 		PROC_LOCK(td->td_proc);
266 		uc.uc_sigmask = td->td_sigmask;
267 		PROC_UNLOCK(td->td_proc);
268 		bzero(&uc.__spare__, sizeof(uc.__spare__));
269 		ret = copyout(&uc, uap->ucp, UC_COPY_SIZE);
270 	}
271 	return (ret);
272 }
273 
274 int
275 freebsd32_setcontext(struct thread *td, struct freebsd32_setcontext_args *uap)
276 {
277 	struct ia32_ucontext uc;
278 	int ret;
279 
280 	if (uap->ucp == NULL)
281 		ret = EINVAL;
282 	else {
283 		ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
284 		if (ret == 0) {
285 			ret = ia32_set_mcontext(td, &uc.uc_mcontext);
286 			if (ret == 0) {
287 				kern_sigprocmask(td, SIG_SETMASK,
288 				    &uc.uc_sigmask, NULL, 0);
289 			}
290 		}
291 	}
292 	return (ret == 0 ? EJUSTRETURN : ret);
293 }
294 
295 int
296 freebsd32_swapcontext(struct thread *td, struct freebsd32_swapcontext_args *uap)
297 {
298 	struct ia32_ucontext uc;
299 	int ret;
300 
301 	if (uap->oucp == NULL || uap->ucp == NULL)
302 		ret = EINVAL;
303 	else {
304 		ia32_get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
305 		PROC_LOCK(td->td_proc);
306 		uc.uc_sigmask = td->td_sigmask;
307 		PROC_UNLOCK(td->td_proc);
308 		ret = copyout(&uc, uap->oucp, UC_COPY_SIZE);
309 		if (ret == 0) {
310 			ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
311 			if (ret == 0) {
312 				ret = ia32_set_mcontext(td, &uc.uc_mcontext);
313 				if (ret == 0) {
314 					kern_sigprocmask(td, SIG_SETMASK,
315 					    &uc.uc_sigmask, NULL, 0);
316 				}
317 			}
318 		}
319 	}
320 	return (ret == 0 ? EJUSTRETURN : ret);
321 }
322 
323 /*
324  * Send an interrupt to process.
325  *
326  * Stack is set up to allow sigcode stored
327  * at top to call routine, followed by kcall
328  * to sigreturn routine below.  After sigreturn
329  * resets the signal mask, the stack, and the
330  * frame pointer, it returns to the user
331  * specified pc, psl.
332  */
333 
334 #ifdef COMPAT_43
335 static void
336 ia32_osendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
337 {
338 	struct ia32_sigframe3 sf, *fp;
339 	struct proc *p;
340 	struct thread *td;
341 	struct sigacts *psp;
342 	struct trapframe *regs;
343 	int sig;
344 	int oonstack;
345 
346 	td = curthread;
347 	p = td->td_proc;
348 	PROC_LOCK_ASSERT(p, MA_OWNED);
349 	sig = ksi->ksi_signo;
350 	psp = p->p_sigacts;
351 	mtx_assert(&psp->ps_mtx, MA_OWNED);
352 	regs = td->td_frame;
353 	oonstack = sigonstack(regs->tf_rsp);
354 
355 	/* Allocate space for the signal handler context. */
356 	if ((td->td_pflags & TDP_ALTSTACK) && !oonstack &&
357 	    SIGISMEMBER(psp->ps_sigonstack, sig)) {
358 		fp = (struct ia32_sigframe3 *)(td->td_sigstk.ss_sp +
359 		    td->td_sigstk.ss_size - sizeof(sf));
360 		td->td_sigstk.ss_flags |= SS_ONSTACK;
361 	} else
362 		fp = (struct ia32_sigframe3 *)regs->tf_rsp - 1;
363 
364 	/* Translate the signal if appropriate. */
365 	if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
366 		sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
367 
368 	/* Build the argument list for the signal handler. */
369 	sf.sf_signum = sig;
370 	sf.sf_scp = (register_t)&fp->sf_siginfo.si_sc;
371 	if (SIGISMEMBER(psp->ps_siginfo, sig)) {
372 		/* Signal handler installed with SA_SIGINFO. */
373 		sf.sf_arg2 = (register_t)&fp->sf_siginfo;
374 		sf.sf_siginfo.si_signo = sig;
375 		sf.sf_siginfo.si_code = ksi->ksi_code;
376 		sf.sf_ah = (uintptr_t)catcher;
377 	} else {
378 		/* Old FreeBSD-style arguments. */
379 		sf.sf_arg2 = ksi->ksi_code;
380 		sf.sf_addr = (register_t)ksi->ksi_addr;
381 		sf.sf_ah = (uintptr_t)catcher;
382 	}
383 	mtx_unlock(&psp->ps_mtx);
384 	PROC_UNLOCK(p);
385 
386 	/* Save most if not all of trap frame. */
387 	sf.sf_siginfo.si_sc.sc_eax = regs->tf_rax;
388 	sf.sf_siginfo.si_sc.sc_ebx = regs->tf_rbx;
389 	sf.sf_siginfo.si_sc.sc_ecx = regs->tf_rcx;
390 	sf.sf_siginfo.si_sc.sc_edx = regs->tf_rdx;
391 	sf.sf_siginfo.si_sc.sc_esi = regs->tf_rsi;
392 	sf.sf_siginfo.si_sc.sc_edi = regs->tf_rdi;
393 	sf.sf_siginfo.si_sc.sc_cs = regs->tf_cs;
394 	sf.sf_siginfo.si_sc.sc_ds = regs->tf_ds;
395 	sf.sf_siginfo.si_sc.sc_ss = regs->tf_ss;
396 	sf.sf_siginfo.si_sc.sc_es = regs->tf_es;
397 	sf.sf_siginfo.si_sc.sc_fs = regs->tf_fs;
398 	sf.sf_siginfo.si_sc.sc_gs = regs->tf_gs;
399 	sf.sf_siginfo.si_sc.sc_isp = regs->tf_rsp;
400 
401 	/* Build the signal context to be used by osigreturn(). */
402 	sf.sf_siginfo.si_sc.sc_onstack = (oonstack) ? 1 : 0;
403 	SIG2OSIG(*mask, sf.sf_siginfo.si_sc.sc_mask);
404 	sf.sf_siginfo.si_sc.sc_esp = regs->tf_rsp;
405 	sf.sf_siginfo.si_sc.sc_ebp = regs->tf_rbp;
406 	sf.sf_siginfo.si_sc.sc_eip = regs->tf_rip;
407 	sf.sf_siginfo.si_sc.sc_eflags = regs->tf_rflags;
408 	sf.sf_siginfo.si_sc.sc_trapno = regs->tf_trapno;
409 	sf.sf_siginfo.si_sc.sc_err = regs->tf_err;
410 
411 	/*
412 	 * Copy the sigframe out to the user's stack.
413 	 */
414 	if (copyout(&sf, fp, sizeof(*fp)) != 0) {
415 #ifdef DEBUG
416 		printf("process %ld has trashed its stack\n", (long)p->p_pid);
417 #endif
418 		PROC_LOCK(p);
419 		sigexit(td, SIGILL);
420 	}
421 
422 	regs->tf_rsp = (uintptr_t)fp;
423 	regs->tf_rip = p->p_sysent->sv_psstrings - sz_ia32_osigcode;
424 	regs->tf_rflags &= ~(PSL_T | PSL_D);
425 	regs->tf_cs = _ucode32sel;
426 	regs->tf_ds = _udatasel;
427 	regs->tf_es = _udatasel;
428 	regs->tf_fs = _udatasel;
429 	regs->tf_ss = _udatasel;
430 	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
431 	PROC_LOCK(p);
432 	mtx_lock(&psp->ps_mtx);
433 }
434 #endif
435 
436 #ifdef COMPAT_FREEBSD4
437 static void
438 freebsd4_ia32_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
439 {
440 	struct ia32_sigframe4 sf, *sfp;
441 	struct siginfo32 siginfo;
442 	struct proc *p;
443 	struct thread *td;
444 	struct sigacts *psp;
445 	struct trapframe *regs;
446 	int oonstack;
447 	int sig;
448 
449 	td = curthread;
450 	p = td->td_proc;
451 	siginfo_to_siginfo32(&ksi->ksi_info, &siginfo);
452 
453 	PROC_LOCK_ASSERT(p, MA_OWNED);
454 	sig = siginfo.si_signo;
455 	psp = p->p_sigacts;
456 	mtx_assert(&psp->ps_mtx, MA_OWNED);
457 	regs = td->td_frame;
458 	oonstack = sigonstack(regs->tf_rsp);
459 
460 	/* Save user context. */
461 	bzero(&sf, sizeof(sf));
462 	sf.sf_uc.uc_sigmask = *mask;
463 	sf.sf_uc.uc_stack.ss_sp = (uintptr_t)td->td_sigstk.ss_sp;
464 	sf.sf_uc.uc_stack.ss_size = td->td_sigstk.ss_size;
465 	sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
466 	    ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
467 	sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
468 	sf.sf_uc.uc_mcontext.mc_edi = regs->tf_rdi;
469 	sf.sf_uc.uc_mcontext.mc_esi = regs->tf_rsi;
470 	sf.sf_uc.uc_mcontext.mc_ebp = regs->tf_rbp;
471 	sf.sf_uc.uc_mcontext.mc_isp = regs->tf_rsp; /* XXX */
472 	sf.sf_uc.uc_mcontext.mc_ebx = regs->tf_rbx;
473 	sf.sf_uc.uc_mcontext.mc_edx = regs->tf_rdx;
474 	sf.sf_uc.uc_mcontext.mc_ecx = regs->tf_rcx;
475 	sf.sf_uc.uc_mcontext.mc_eax = regs->tf_rax;
476 	sf.sf_uc.uc_mcontext.mc_trapno = regs->tf_trapno;
477 	sf.sf_uc.uc_mcontext.mc_err = regs->tf_err;
478 	sf.sf_uc.uc_mcontext.mc_eip = regs->tf_rip;
479 	sf.sf_uc.uc_mcontext.mc_cs = regs->tf_cs;
480 	sf.sf_uc.uc_mcontext.mc_eflags = regs->tf_rflags;
481 	sf.sf_uc.uc_mcontext.mc_esp = regs->tf_rsp;
482 	sf.sf_uc.uc_mcontext.mc_ss = regs->tf_ss;
483 	sf.sf_uc.uc_mcontext.mc_ds = regs->tf_ds;
484 	sf.sf_uc.uc_mcontext.mc_es = regs->tf_es;
485 	sf.sf_uc.uc_mcontext.mc_fs = regs->tf_fs;
486 	sf.sf_uc.uc_mcontext.mc_gs = regs->tf_gs;
487 	bzero(sf.sf_uc.uc_mcontext.mc_fpregs,
488 	    sizeof(sf.sf_uc.uc_mcontext.mc_fpregs));
489 	bzero(sf.sf_uc.uc_mcontext.__spare__,
490 	    sizeof(sf.sf_uc.uc_mcontext.__spare__));
491 	bzero(sf.sf_uc.__spare__, sizeof(sf.sf_uc.__spare__));
492 
493 	/* Allocate space for the signal handler context. */
494 	if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
495 	    SIGISMEMBER(psp->ps_sigonstack, sig)) {
496 		sfp = (struct ia32_sigframe4 *)(td->td_sigstk.ss_sp +
497 		    td->td_sigstk.ss_size - sizeof(sf));
498 	} else
499 		sfp = (struct ia32_sigframe4 *)regs->tf_rsp - 1;
500 	PROC_UNLOCK(p);
501 
502 	/* Translate the signal if appropriate. */
503 	if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
504 		sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
505 
506 	/* Build the argument list for the signal handler. */
507 	sf.sf_signum = sig;
508 	sf.sf_ucontext = (register_t)&sfp->sf_uc;
509 	bzero(&sf.sf_si, sizeof(sf.sf_si));
510 	if (SIGISMEMBER(psp->ps_siginfo, sig)) {
511 		/* Signal handler installed with SA_SIGINFO. */
512 		sf.sf_siginfo = (u_int32_t)(uintptr_t)&sfp->sf_si;
513 		sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
514 
515 		/* Fill in POSIX parts */
516 		sf.sf_si = siginfo;
517 		sf.sf_si.si_signo = sig;
518 	} else {
519 		/* Old FreeBSD-style arguments. */
520 		sf.sf_siginfo = siginfo.si_code;
521 		sf.sf_addr = (u_int32_t)siginfo.si_addr;
522 		sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
523 	}
524 	mtx_unlock(&psp->ps_mtx);
525 
526 	/*
527 	 * Copy the sigframe out to the user's stack.
528 	 */
529 	if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
530 #ifdef DEBUG
531 		printf("process %ld has trashed its stack\n", (long)p->p_pid);
532 #endif
533 		PROC_LOCK(p);
534 		sigexit(td, SIGILL);
535 	}
536 
537 	regs->tf_rsp = (uintptr_t)sfp;
538 	regs->tf_rip = p->p_sysent->sv_sigcode_base + sz_ia32_sigcode -
539 	    sz_freebsd4_ia32_sigcode;
540 	regs->tf_rflags &= ~(PSL_T | PSL_D);
541 	regs->tf_cs = _ucode32sel;
542 	regs->tf_ss = _udatasel;
543 	regs->tf_ds = _udatasel;
544 	regs->tf_es = _udatasel;
545 	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
546 	/* leave user %fs and %gs untouched */
547 	PROC_LOCK(p);
548 	mtx_lock(&psp->ps_mtx);
549 }
550 #endif	/* COMPAT_FREEBSD4 */
551 
552 void
553 ia32_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
554 {
555 	struct ia32_sigframe sf, *sfp;
556 	struct siginfo32 siginfo;
557 	struct proc *p;
558 	struct thread *td;
559 	struct sigacts *psp;
560 	char *sp;
561 	struct trapframe *regs;
562 	char *xfpusave;
563 	size_t xfpusave_len;
564 	int oonstack;
565 	int sig;
566 
567 	siginfo_to_siginfo32(&ksi->ksi_info, &siginfo);
568 	td = curthread;
569 	p = td->td_proc;
570 	PROC_LOCK_ASSERT(p, MA_OWNED);
571 	sig = siginfo.si_signo;
572 	psp = p->p_sigacts;
573 #ifdef COMPAT_FREEBSD4
574 	if (SIGISMEMBER(psp->ps_freebsd4, sig)) {
575 		freebsd4_ia32_sendsig(catcher, ksi, mask);
576 		return;
577 	}
578 #endif
579 #ifdef COMPAT_43
580 	if (SIGISMEMBER(psp->ps_osigset, sig)) {
581 		ia32_osendsig(catcher, ksi, mask);
582 		return;
583 	}
584 #endif
585 	mtx_assert(&psp->ps_mtx, MA_OWNED);
586 	regs = td->td_frame;
587 	oonstack = sigonstack(regs->tf_rsp);
588 
589 	if (cpu_max_ext_state_size > sizeof(struct savefpu) && use_xsave) {
590 		xfpusave_len = cpu_max_ext_state_size - sizeof(struct savefpu);
591 		xfpusave = __builtin_alloca(xfpusave_len);
592 	} else {
593 		xfpusave_len = 0;
594 		xfpusave = NULL;
595 	}
596 
597 	/* Save user context. */
598 	bzero(&sf, sizeof(sf));
599 	sf.sf_uc.uc_sigmask = *mask;
600 	sf.sf_uc.uc_stack.ss_sp = (uintptr_t)td->td_sigstk.ss_sp;
601 	sf.sf_uc.uc_stack.ss_size = td->td_sigstk.ss_size;
602 	sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
603 	    ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
604 	sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
605 	sf.sf_uc.uc_mcontext.mc_edi = regs->tf_rdi;
606 	sf.sf_uc.uc_mcontext.mc_esi = regs->tf_rsi;
607 	sf.sf_uc.uc_mcontext.mc_ebp = regs->tf_rbp;
608 	sf.sf_uc.uc_mcontext.mc_isp = regs->tf_rsp; /* XXX */
609 	sf.sf_uc.uc_mcontext.mc_ebx = regs->tf_rbx;
610 	sf.sf_uc.uc_mcontext.mc_edx = regs->tf_rdx;
611 	sf.sf_uc.uc_mcontext.mc_ecx = regs->tf_rcx;
612 	sf.sf_uc.uc_mcontext.mc_eax = regs->tf_rax;
613 	sf.sf_uc.uc_mcontext.mc_trapno = regs->tf_trapno;
614 	sf.sf_uc.uc_mcontext.mc_err = regs->tf_err;
615 	sf.sf_uc.uc_mcontext.mc_eip = regs->tf_rip;
616 	sf.sf_uc.uc_mcontext.mc_cs = regs->tf_cs;
617 	sf.sf_uc.uc_mcontext.mc_eflags = regs->tf_rflags;
618 	sf.sf_uc.uc_mcontext.mc_esp = regs->tf_rsp;
619 	sf.sf_uc.uc_mcontext.mc_ss = regs->tf_ss;
620 	sf.sf_uc.uc_mcontext.mc_ds = regs->tf_ds;
621 	sf.sf_uc.uc_mcontext.mc_es = regs->tf_es;
622 	sf.sf_uc.uc_mcontext.mc_fs = regs->tf_fs;
623 	sf.sf_uc.uc_mcontext.mc_gs = regs->tf_gs;
624 	sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */
625 	ia32_get_fpcontext(td, &sf.sf_uc.uc_mcontext, xfpusave, xfpusave_len);
626 	fpstate_drop(td);
627 	sf.sf_uc.uc_mcontext.mc_fsbase = td->td_pcb->pcb_fsbase;
628 	sf.sf_uc.uc_mcontext.mc_gsbase = td->td_pcb->pcb_gsbase;
629 	bzero(sf.sf_uc.__spare__, sizeof(sf.sf_uc.__spare__));
630 
631 	/* Allocate space for the signal handler context. */
632 	if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
633 	    SIGISMEMBER(psp->ps_sigonstack, sig))
634 		sp = td->td_sigstk.ss_sp + td->td_sigstk.ss_size;
635 	else
636 		sp = (char *)regs->tf_rsp;
637 	if (xfpusave != NULL) {
638 		sp -= xfpusave_len;
639 		sp = (char *)((unsigned long)sp & ~0x3Ful);
640 		sf.sf_uc.uc_mcontext.mc_xfpustate = (register_t)sp;
641 	}
642 	sp -= sizeof(sf);
643 	/* Align to 16 bytes. */
644 	sfp = (struct ia32_sigframe *)((uintptr_t)sp & ~0xF);
645 	PROC_UNLOCK(p);
646 
647 	/* Translate the signal if appropriate. */
648 	if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
649 		sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
650 
651 	/* Build the argument list for the signal handler. */
652 	sf.sf_signum = sig;
653 	sf.sf_ucontext = (register_t)&sfp->sf_uc;
654 	bzero(&sf.sf_si, sizeof(sf.sf_si));
655 	if (SIGISMEMBER(psp->ps_siginfo, sig)) {
656 		/* Signal handler installed with SA_SIGINFO. */
657 		sf.sf_siginfo = (u_int32_t)(uintptr_t)&sfp->sf_si;
658 		sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
659 
660 		/* Fill in POSIX parts */
661 		sf.sf_si = siginfo;
662 		sf.sf_si.si_signo = sig;
663 	} else {
664 		/* Old FreeBSD-style arguments. */
665 		sf.sf_siginfo = siginfo.si_code;
666 		sf.sf_addr = (u_int32_t)siginfo.si_addr;
667 		sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
668 	}
669 	mtx_unlock(&psp->ps_mtx);
670 
671 	/*
672 	 * Copy the sigframe out to the user's stack.
673 	 */
674 	if (copyout(&sf, sfp, sizeof(*sfp)) != 0 ||
675 	    (xfpusave != NULL && copyout(xfpusave,
676 	    PTRIN(sf.sf_uc.uc_mcontext.mc_xfpustate), xfpusave_len)
677 	    != 0)) {
678 #ifdef DEBUG
679 		printf("process %ld has trashed its stack\n", (long)p->p_pid);
680 #endif
681 		PROC_LOCK(p);
682 		sigexit(td, SIGILL);
683 	}
684 
685 	regs->tf_rsp = (uintptr_t)sfp;
686 	regs->tf_rip = p->p_sysent->sv_sigcode_base;
687 	regs->tf_rflags &= ~(PSL_T | PSL_D);
688 	regs->tf_cs = _ucode32sel;
689 	regs->tf_ss = _udatasel;
690 	regs->tf_ds = _udatasel;
691 	regs->tf_es = _udatasel;
692 	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
693 	/* XXXKIB leave user %fs and %gs untouched */
694 	PROC_LOCK(p);
695 	mtx_lock(&psp->ps_mtx);
696 }
697 
698 /*
699  * System call to cleanup state after a signal
700  * has been taken.  Reset signal mask and
701  * stack state from context left by sendsig (above).
702  * Return to previous pc and psl as specified by
703  * context left by sendsig. Check carefully to
704  * make sure that the user has not modified the
705  * state to gain improper privileges.
706  */
707 
708 #ifdef COMPAT_43
709 int
710 ofreebsd32_sigreturn(struct thread *td, struct ofreebsd32_sigreturn_args *uap)
711 {
712 	struct ia32_sigcontext3 sc, *scp;
713 	struct trapframe *regs;
714 	int eflags, error;
715 	ksiginfo_t ksi;
716 
717 	regs = td->td_frame;
718 	error = copyin(uap->sigcntxp, &sc, sizeof(sc));
719 	if (error != 0)
720 		return (error);
721 	scp = &sc;
722 	eflags = scp->sc_eflags;
723 	if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) {
724 		return (EINVAL);
725 	}
726 	if (!CS_SECURE(scp->sc_cs)) {
727 		ksiginfo_init_trap(&ksi);
728 		ksi.ksi_signo = SIGBUS;
729 		ksi.ksi_code = BUS_OBJERR;
730 		ksi.ksi_trapno = T_PROTFLT;
731 		ksi.ksi_addr = (void *)regs->tf_rip;
732 		trapsignal(td, &ksi);
733 		return (EINVAL);
734 	}
735 	regs->tf_ds = scp->sc_ds;
736 	regs->tf_es = scp->sc_es;
737 	regs->tf_fs = scp->sc_fs;
738 	regs->tf_gs = scp->sc_gs;
739 
740 	regs->tf_rax = scp->sc_eax;
741 	regs->tf_rbx = scp->sc_ebx;
742 	regs->tf_rcx = scp->sc_ecx;
743 	regs->tf_rdx = scp->sc_edx;
744 	regs->tf_rsi = scp->sc_esi;
745 	regs->tf_rdi = scp->sc_edi;
746 	regs->tf_cs = scp->sc_cs;
747 	regs->tf_ss = scp->sc_ss;
748 	regs->tf_rbp = scp->sc_ebp;
749 	regs->tf_rsp = scp->sc_esp;
750 	regs->tf_rip = scp->sc_eip;
751 	regs->tf_rflags = eflags;
752 
753 	if (scp->sc_onstack & 1)
754 		td->td_sigstk.ss_flags |= SS_ONSTACK;
755 	else
756 		td->td_sigstk.ss_flags &= ~SS_ONSTACK;
757 
758 	kern_sigprocmask(td, SIG_SETMASK, (sigset_t *)&scp->sc_mask, NULL,
759 	    SIGPROCMASK_OLD);
760 	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
761 	return (EJUSTRETURN);
762 }
763 #endif
764 
765 #ifdef COMPAT_FREEBSD4
766 /*
767  * MPSAFE
768  */
769 int
770 freebsd4_freebsd32_sigreturn(td, uap)
771 	struct thread *td;
772 	struct freebsd4_freebsd32_sigreturn_args /* {
773 		const struct freebsd4_freebsd32_ucontext *sigcntxp;
774 	} */ *uap;
775 {
776 	struct ia32_ucontext4 uc;
777 	struct trapframe *regs;
778 	struct ia32_ucontext4 *ucp;
779 	int cs, eflags, error;
780 	ksiginfo_t ksi;
781 
782 	error = copyin(uap->sigcntxp, &uc, sizeof(uc));
783 	if (error != 0)
784 		return (error);
785 	ucp = &uc;
786 	regs = td->td_frame;
787 	eflags = ucp->uc_mcontext.mc_eflags;
788 	/*
789 	 * Don't allow users to change privileged or reserved flags.
790 	 */
791 	/*
792 	 * XXX do allow users to change the privileged flag PSL_RF.
793 	 * The cpu sets PSL_RF in tf_eflags for faults.  Debuggers
794 	 * should sometimes set it there too.  tf_eflags is kept in
795 	 * the signal context during signal handling and there is no
796 	 * other place to remember it, so the PSL_RF bit may be
797 	 * corrupted by the signal handler without us knowing.
798 	 * Corruption of the PSL_RF bit at worst causes one more or
799 	 * one less debugger trap, so allowing it is fairly harmless.
800 	 */
801 	if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) {
802 		uprintf("pid %d (%s): freebsd4_freebsd32_sigreturn eflags = 0x%x\n",
803 		    td->td_proc->p_pid, td->td_name, eflags);
804 		return (EINVAL);
805 	}
806 
807 	/*
808 	 * Don't allow users to load a valid privileged %cs.  Let the
809 	 * hardware check for invalid selectors, excess privilege in
810 	 * other selectors, invalid %eip's and invalid %esp's.
811 	 */
812 	cs = ucp->uc_mcontext.mc_cs;
813 	if (!CS_SECURE(cs)) {
814 		uprintf("pid %d (%s): freebsd4_sigreturn cs = 0x%x\n",
815 		    td->td_proc->p_pid, td->td_name, cs);
816 		ksiginfo_init_trap(&ksi);
817 		ksi.ksi_signo = SIGBUS;
818 		ksi.ksi_code = BUS_OBJERR;
819 		ksi.ksi_trapno = T_PROTFLT;
820 		ksi.ksi_addr = (void *)regs->tf_rip;
821 		trapsignal(td, &ksi);
822 		return (EINVAL);
823 	}
824 
825 	regs->tf_rdi = ucp->uc_mcontext.mc_edi;
826 	regs->tf_rsi = ucp->uc_mcontext.mc_esi;
827 	regs->tf_rbp = ucp->uc_mcontext.mc_ebp;
828 	regs->tf_rbx = ucp->uc_mcontext.mc_ebx;
829 	regs->tf_rdx = ucp->uc_mcontext.mc_edx;
830 	regs->tf_rcx = ucp->uc_mcontext.mc_ecx;
831 	regs->tf_rax = ucp->uc_mcontext.mc_eax;
832 	regs->tf_trapno = ucp->uc_mcontext.mc_trapno;
833 	regs->tf_err = ucp->uc_mcontext.mc_err;
834 	regs->tf_rip = ucp->uc_mcontext.mc_eip;
835 	regs->tf_cs = cs;
836 	regs->tf_rflags = ucp->uc_mcontext.mc_eflags;
837 	regs->tf_rsp = ucp->uc_mcontext.mc_esp;
838 	regs->tf_ss = ucp->uc_mcontext.mc_ss;
839 	regs->tf_ds = ucp->uc_mcontext.mc_ds;
840 	regs->tf_es = ucp->uc_mcontext.mc_es;
841 	regs->tf_fs = ucp->uc_mcontext.mc_fs;
842 	regs->tf_gs = ucp->uc_mcontext.mc_gs;
843 
844 	kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0);
845 	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
846 	return (EJUSTRETURN);
847 }
848 #endif	/* COMPAT_FREEBSD4 */
849 
850 /*
851  * MPSAFE
852  */
853 int
854 freebsd32_sigreturn(td, uap)
855 	struct thread *td;
856 	struct freebsd32_sigreturn_args /* {
857 		const struct freebsd32_ucontext *sigcntxp;
858 	} */ *uap;
859 {
860 	struct ia32_ucontext uc;
861 	struct trapframe *regs;
862 	struct ia32_ucontext *ucp;
863 	char *xfpustate;
864 	size_t xfpustate_len;
865 	int cs, eflags, error, ret;
866 	ksiginfo_t ksi;
867 
868 	error = copyin(uap->sigcntxp, &uc, sizeof(uc));
869 	if (error != 0)
870 		return (error);
871 	ucp = &uc;
872 	regs = td->td_frame;
873 	eflags = ucp->uc_mcontext.mc_eflags;
874 	/*
875 	 * Don't allow users to change privileged or reserved flags.
876 	 */
877 	/*
878 	 * XXX do allow users to change the privileged flag PSL_RF.
879 	 * The cpu sets PSL_RF in tf_eflags for faults.  Debuggers
880 	 * should sometimes set it there too.  tf_eflags is kept in
881 	 * the signal context during signal handling and there is no
882 	 * other place to remember it, so the PSL_RF bit may be
883 	 * corrupted by the signal handler without us knowing.
884 	 * Corruption of the PSL_RF bit at worst causes one more or
885 	 * one less debugger trap, so allowing it is fairly harmless.
886 	 */
887 	if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) {
888 		uprintf("pid %d (%s): freebsd32_sigreturn eflags = 0x%x\n",
889 		    td->td_proc->p_pid, td->td_name, eflags);
890 		return (EINVAL);
891 	}
892 
893 	/*
894 	 * Don't allow users to load a valid privileged %cs.  Let the
895 	 * hardware check for invalid selectors, excess privilege in
896 	 * other selectors, invalid %eip's and invalid %esp's.
897 	 */
898 	cs = ucp->uc_mcontext.mc_cs;
899 	if (!CS_SECURE(cs)) {
900 		uprintf("pid %d (%s): sigreturn cs = 0x%x\n",
901 		    td->td_proc->p_pid, td->td_name, cs);
902 		ksiginfo_init_trap(&ksi);
903 		ksi.ksi_signo = SIGBUS;
904 		ksi.ksi_code = BUS_OBJERR;
905 		ksi.ksi_trapno = T_PROTFLT;
906 		ksi.ksi_addr = (void *)regs->tf_rip;
907 		trapsignal(td, &ksi);
908 		return (EINVAL);
909 	}
910 
911 	if ((ucp->uc_mcontext.mc_flags & _MC_HASFPXSTATE) != 0) {
912 		xfpustate_len = uc.uc_mcontext.mc_xfpustate_len;
913 		if (xfpustate_len > cpu_max_ext_state_size -
914 		    sizeof(struct savefpu)) {
915 			uprintf("pid %d (%s): sigreturn xfpusave_len = 0x%zx\n",
916 			    td->td_proc->p_pid, td->td_name, xfpustate_len);
917 			return (EINVAL);
918 		}
919 		xfpustate = __builtin_alloca(xfpustate_len);
920 		error = copyin(PTRIN(ucp->uc_mcontext.mc_xfpustate),
921 		    xfpustate, xfpustate_len);
922 		if (error != 0) {
923 			uprintf(
924 	"pid %d (%s): sigreturn copying xfpustate failed\n",
925 			    td->td_proc->p_pid, td->td_name);
926 			return (error);
927 		}
928 	} else {
929 		xfpustate = NULL;
930 		xfpustate_len = 0;
931 	}
932 	ret = ia32_set_fpcontext(td, &ucp->uc_mcontext, xfpustate,
933 	    xfpustate_len);
934 	if (ret != 0) {
935 		uprintf("pid %d (%s): sigreturn set_fpcontext err %d\n",
936 		    td->td_proc->p_pid, td->td_name, ret);
937 		return (ret);
938 	}
939 
940 	regs->tf_rdi = ucp->uc_mcontext.mc_edi;
941 	regs->tf_rsi = ucp->uc_mcontext.mc_esi;
942 	regs->tf_rbp = ucp->uc_mcontext.mc_ebp;
943 	regs->tf_rbx = ucp->uc_mcontext.mc_ebx;
944 	regs->tf_rdx = ucp->uc_mcontext.mc_edx;
945 	regs->tf_rcx = ucp->uc_mcontext.mc_ecx;
946 	regs->tf_rax = ucp->uc_mcontext.mc_eax;
947 	regs->tf_trapno = ucp->uc_mcontext.mc_trapno;
948 	regs->tf_err = ucp->uc_mcontext.mc_err;
949 	regs->tf_rip = ucp->uc_mcontext.mc_eip;
950 	regs->tf_cs = cs;
951 	regs->tf_rflags = ucp->uc_mcontext.mc_eflags;
952 	regs->tf_rsp = ucp->uc_mcontext.mc_esp;
953 	regs->tf_ss = ucp->uc_mcontext.mc_ss;
954 	regs->tf_ds = ucp->uc_mcontext.mc_ds;
955 	regs->tf_es = ucp->uc_mcontext.mc_es;
956 	regs->tf_fs = ucp->uc_mcontext.mc_fs;
957 	regs->tf_gs = ucp->uc_mcontext.mc_gs;
958 	regs->tf_flags = TF_HASSEGS;
959 
960 	kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0);
961 	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
962 	return (EJUSTRETURN);
963 }
964 
965 /*
966  * Clear registers on exec
967  */
968 void
969 ia32_setregs(struct thread *td, struct image_params *imgp, u_long stack)
970 {
971 	struct trapframe *regs = td->td_frame;
972 	struct pcb *pcb = td->td_pcb;
973 
974 	mtx_lock(&dt_lock);
975 	if (td->td_proc->p_md.md_ldt != NULL)
976 		user_ldt_free(td);
977 	else
978 		mtx_unlock(&dt_lock);
979 #ifdef COMPAT_43
980 	setup_lcall_gate();
981 #endif
982 
983 	pcb->pcb_fsbase = 0;
984 	pcb->pcb_gsbase = 0;
985 	pcb->pcb_initial_fpucw = __INITIAL_FPUCW_I386__;
986 
987 	bzero((char *)regs, sizeof(struct trapframe));
988 	regs->tf_rip = imgp->entry_addr;
989 	regs->tf_rsp = stack;
990 	regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T);
991 	regs->tf_ss = _udatasel;
992 	regs->tf_cs = _ucode32sel;
993 	regs->tf_rbx = imgp->ps_strings;
994 	regs->tf_ds = _udatasel;
995 	regs->tf_es = _udatasel;
996 	regs->tf_fs = _ufssel;
997 	regs->tf_gs = _ugssel;
998 	regs->tf_flags = TF_HASSEGS;
999 
1000 	fpstate_drop(td);
1001 
1002 	/* Return via doreti so that we can change to a different %cs */
1003 	set_pcb_flags(pcb, PCB_32BIT | PCB_FULL_IRET);
1004 	clear_pcb_flags(pcb, PCB_GS32BIT);
1005 	td->td_retval[1] = 0;
1006 }
1007