1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2003 Peter Wemm
5 * Copyright (c) 1982, 1987, 1990 The Regents of the University of California.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * William Jolitz.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD$");
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#include <machine/trap.h>
84
85#ifdef COMPAT_FREEBSD4
86static void freebsd4_ia32_sendsig(sig_t, ksiginfo_t *, sigset_t *);
87#endif
88
89#define	CS_SECURE(cs)		(ISPL(cs) == SEL_UPL)
90#define	EFL_SECURE(ef, oef)	((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
91
92static void
93ia32_get_fpcontext(struct thread *td, struct ia32_mcontext *mcp,
94    char *xfpusave, size_t xfpusave_len)
95{
96	size_t max_len, len;
97
98	/*
99	 * XXX Format of 64bit and 32bit FXSAVE areas differs. FXSAVE
100	 * in 32bit mode saves %cs and %ds, while on 64bit it saves
101	 * 64bit instruction and data pointers. Ignore the difference
102	 * for now, it should be irrelevant for most applications.
103	 */
104	mcp->mc_ownedfp = fpugetregs(td);
105	bcopy(get_pcb_user_save_td(td), &mcp->mc_fpstate[0],
106	    sizeof(mcp->mc_fpstate));
107	mcp->mc_fpformat = fpuformat();
108	if (!use_xsave || xfpusave_len == 0)
109		return;
110	max_len = cpu_max_ext_state_size - sizeof(struct savefpu);
111	len = xfpusave_len;
112	if (len > max_len) {
113		len = max_len;
114		bzero(xfpusave + max_len, len - max_len);
115	}
116	mcp->mc_flags |= _MC_IA32_HASFPXSTATE;
117	mcp->mc_xfpustate_len = len;
118	bcopy(get_pcb_user_save_td(td) + 1, xfpusave, len);
119}
120
121static int
122ia32_set_fpcontext(struct thread *td, struct ia32_mcontext *mcp,
123    char *xfpustate, size_t xfpustate_len)
124{
125	int error;
126
127	if (mcp->mc_fpformat == _MC_FPFMT_NODEV)
128		return (0);
129	else if (mcp->mc_fpformat != _MC_FPFMT_XMM)
130		return (EINVAL);
131	else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE) {
132		/* We don't care what state is left in the FPU or PCB. */
133		fpstate_drop(td);
134		error = 0;
135	} else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU ||
136	    mcp->mc_ownedfp == _MC_FPOWNED_PCB) {
137		error = fpusetregs(td, (struct savefpu *)&mcp->mc_fpstate,
138		    xfpustate, xfpustate_len);
139	} else
140		return (EINVAL);
141	return (error);
142}
143
144/*
145 * Get machine context.
146 */
147static int
148ia32_get_mcontext(struct thread *td, struct ia32_mcontext *mcp, int flags)
149{
150	struct pcb *pcb;
151	struct trapframe *tp;
152
153	pcb = td->td_pcb;
154	tp = td->td_frame;
155
156	PROC_LOCK(curthread->td_proc);
157	mcp->mc_onstack = sigonstack(tp->tf_rsp);
158	PROC_UNLOCK(curthread->td_proc);
159	/* Entry into kernel always sets TF_HASSEGS */
160	mcp->mc_gs = tp->tf_gs;
161	mcp->mc_fs = tp->tf_fs;
162	mcp->mc_es = tp->tf_es;
163	mcp->mc_ds = tp->tf_ds;
164	mcp->mc_edi = tp->tf_rdi;
165	mcp->mc_esi = tp->tf_rsi;
166	mcp->mc_ebp = tp->tf_rbp;
167	mcp->mc_isp = tp->tf_rsp;
168	mcp->mc_eflags = tp->tf_rflags;
169	if (flags & GET_MC_CLEAR_RET) {
170		mcp->mc_eax = 0;
171		mcp->mc_edx = 0;
172		mcp->mc_eflags &= ~PSL_C;
173	} else {
174		mcp->mc_eax = tp->tf_rax;
175		mcp->mc_edx = tp->tf_rdx;
176	}
177	mcp->mc_ebx = tp->tf_rbx;
178	mcp->mc_ecx = tp->tf_rcx;
179	mcp->mc_eip = tp->tf_rip;
180	mcp->mc_cs = tp->tf_cs;
181	mcp->mc_esp = tp->tf_rsp;
182	mcp->mc_ss = tp->tf_ss;
183	mcp->mc_len = sizeof(*mcp);
184	mcp->mc_flags = tp->tf_flags;
185	ia32_get_fpcontext(td, mcp, NULL, 0);
186	mcp->mc_fsbase = pcb->pcb_fsbase;
187	mcp->mc_gsbase = pcb->pcb_gsbase;
188	mcp->mc_xfpustate = 0;
189	mcp->mc_xfpustate_len = 0;
190	bzero(mcp->mc_spare2, sizeof(mcp->mc_spare2));
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 */
200static int
201ia32_set_mcontext(struct thread *td, 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
255int
256freebsd32_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		bzero(&uc, sizeof(uc));
265		ia32_get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
266		PROC_LOCK(td->td_proc);
267		uc.uc_sigmask = td->td_sigmask;
268		PROC_UNLOCK(td->td_proc);
269		bzero(&uc.__spare__, sizeof(uc.__spare__));
270		ret = copyout(&uc, uap->ucp, UC_COPY_SIZE);
271	}
272	return (ret);
273}
274
275int
276freebsd32_setcontext(struct thread *td, struct freebsd32_setcontext_args *uap)
277{
278	struct ia32_ucontext uc;
279	int ret;
280
281	if (uap->ucp == NULL)
282		ret = EINVAL;
283	else {
284		ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
285		if (ret == 0) {
286			ret = ia32_set_mcontext(td, &uc.uc_mcontext);
287			if (ret == 0) {
288				kern_sigprocmask(td, SIG_SETMASK,
289				    &uc.uc_sigmask, NULL, 0);
290			}
291		}
292	}
293	return (ret == 0 ? EJUSTRETURN : ret);
294}
295
296int
297freebsd32_swapcontext(struct thread *td, struct freebsd32_swapcontext_args *uap)
298{
299	struct ia32_ucontext uc;
300	int ret;
301
302	if (uap->oucp == NULL || uap->ucp == NULL)
303		ret = EINVAL;
304	else {
305		bzero(&uc, sizeof(uc));
306		ia32_get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
307		PROC_LOCK(td->td_proc);
308		uc.uc_sigmask = td->td_sigmask;
309		PROC_UNLOCK(td->td_proc);
310		ret = copyout(&uc, uap->oucp, UC_COPY_SIZE);
311		if (ret == 0) {
312			ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
313			if (ret == 0) {
314				ret = ia32_set_mcontext(td, &uc.uc_mcontext);
315				if (ret == 0) {
316					kern_sigprocmask(td, SIG_SETMASK,
317					    &uc.uc_sigmask, NULL, 0);
318				}
319			}
320		}
321	}
322	return (ret == 0 ? EJUSTRETURN : ret);
323}
324
325/*
326 * Send an interrupt to process.
327 *
328 * Stack is set up to allow sigcode stored
329 * at top to call routine, followed by kcall
330 * to sigreturn routine below.  After sigreturn
331 * resets the signal mask, the stack, and the
332 * frame pointer, it returns to the user
333 * specified pc, psl.
334 */
335
336#ifdef COMPAT_43
337static void
338ia32_osendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
339{
340	struct ia32_sigframe3 sf, *fp;
341	struct proc *p;
342	struct thread *td;
343	struct sigacts *psp;
344	struct trapframe *regs;
345	int sig;
346	int oonstack;
347
348	td = curthread;
349	p = td->td_proc;
350	PROC_LOCK_ASSERT(p, MA_OWNED);
351	sig = ksi->ksi_signo;
352	psp = p->p_sigacts;
353	mtx_assert(&psp->ps_mtx, MA_OWNED);
354	regs = td->td_frame;
355	oonstack = sigonstack(regs->tf_rsp);
356
357	/* Allocate space for the signal handler context. */
358	if ((td->td_pflags & TDP_ALTSTACK) && !oonstack &&
359	    SIGISMEMBER(psp->ps_sigonstack, sig)) {
360		fp = (struct ia32_sigframe3 *)((uintptr_t)td->td_sigstk.ss_sp +
361		    td->td_sigstk.ss_size - sizeof(sf));
362		td->td_sigstk.ss_flags |= SS_ONSTACK;
363	} else
364		fp = (struct ia32_sigframe3 *)regs->tf_rsp - 1;
365
366	/* Build the argument list for the signal handler. */
367	sf.sf_signum = sig;
368	sf.sf_scp = (register_t)&fp->sf_siginfo.si_sc;
369	bzero(&sf.sf_siginfo, sizeof(sf.sf_siginfo));
370	if (SIGISMEMBER(psp->ps_siginfo, sig)) {
371		/* Signal handler installed with SA_SIGINFO. */
372		sf.sf_arg2 = (register_t)&fp->sf_siginfo;
373		sf.sf_siginfo.si_signo = sig;
374		sf.sf_siginfo.si_code = ksi->ksi_code;
375		sf.sf_ah = (uintptr_t)catcher;
376		sf.sf_addr = 0;
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
437static void
438freebsd4_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 *)((uintptr_t)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	/* Build the argument list for the signal handler. */
503	sf.sf_signum = sig;
504	sf.sf_ucontext = (register_t)&sfp->sf_uc;
505	bzero(&sf.sf_si, sizeof(sf.sf_si));
506	if (SIGISMEMBER(psp->ps_siginfo, sig)) {
507		/* Signal handler installed with SA_SIGINFO. */
508		sf.sf_siginfo = (u_int32_t)(uintptr_t)&sfp->sf_si;
509		sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
510
511		/* Fill in POSIX parts */
512		sf.sf_si = siginfo;
513		sf.sf_si.si_signo = sig;
514	} else {
515		/* Old FreeBSD-style arguments. */
516		sf.sf_siginfo = siginfo.si_code;
517		sf.sf_addr = (u_int32_t)siginfo.si_addr;
518		sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
519	}
520	mtx_unlock(&psp->ps_mtx);
521
522	/*
523	 * Copy the sigframe out to the user's stack.
524	 */
525	if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
526#ifdef DEBUG
527		printf("process %ld has trashed its stack\n", (long)p->p_pid);
528#endif
529		PROC_LOCK(p);
530		sigexit(td, SIGILL);
531	}
532
533	regs->tf_rsp = (uintptr_t)sfp;
534	regs->tf_rip = p->p_sysent->sv_sigcode_base + sz_ia32_sigcode -
535	    sz_freebsd4_ia32_sigcode;
536	regs->tf_rflags &= ~(PSL_T | PSL_D);
537	regs->tf_cs = _ucode32sel;
538	regs->tf_ss = _udatasel;
539	regs->tf_ds = _udatasel;
540	regs->tf_es = _udatasel;
541	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
542	/* leave user %fs and %gs untouched */
543	PROC_LOCK(p);
544	mtx_lock(&psp->ps_mtx);
545}
546#endif	/* COMPAT_FREEBSD4 */
547
548void
549ia32_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
550{
551	struct ia32_sigframe sf, *sfp;
552	struct siginfo32 siginfo;
553	struct proc *p;
554	struct thread *td;
555	struct sigacts *psp;
556	char *sp;
557	struct trapframe *regs;
558	char *xfpusave;
559	size_t xfpusave_len;
560	int oonstack;
561	int sig;
562
563	siginfo_to_siginfo32(&ksi->ksi_info, &siginfo);
564	td = curthread;
565	p = td->td_proc;
566	PROC_LOCK_ASSERT(p, MA_OWNED);
567	sig = siginfo.si_signo;
568	psp = p->p_sigacts;
569#ifdef COMPAT_FREEBSD4
570	if (SIGISMEMBER(psp->ps_freebsd4, sig)) {
571		freebsd4_ia32_sendsig(catcher, ksi, mask);
572		return;
573	}
574#endif
575#ifdef COMPAT_43
576	if (SIGISMEMBER(psp->ps_osigset, sig)) {
577		ia32_osendsig(catcher, ksi, mask);
578		return;
579	}
580#endif
581	mtx_assert(&psp->ps_mtx, MA_OWNED);
582	regs = td->td_frame;
583	oonstack = sigonstack(regs->tf_rsp);
584
585	if (cpu_max_ext_state_size > sizeof(struct savefpu) && use_xsave) {
586		xfpusave_len = cpu_max_ext_state_size - sizeof(struct savefpu);
587		xfpusave = __builtin_alloca(xfpusave_len);
588	} else {
589		xfpusave_len = 0;
590		xfpusave = NULL;
591	}
592
593	/* Save user context. */
594	bzero(&sf, sizeof(sf));
595	sf.sf_uc.uc_sigmask = *mask;
596	sf.sf_uc.uc_stack.ss_sp = (uintptr_t)td->td_sigstk.ss_sp;
597	sf.sf_uc.uc_stack.ss_size = td->td_sigstk.ss_size;
598	sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
599	    ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
600	sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
601	sf.sf_uc.uc_mcontext.mc_edi = regs->tf_rdi;
602	sf.sf_uc.uc_mcontext.mc_esi = regs->tf_rsi;
603	sf.sf_uc.uc_mcontext.mc_ebp = regs->tf_rbp;
604	sf.sf_uc.uc_mcontext.mc_isp = regs->tf_rsp; /* XXX */
605	sf.sf_uc.uc_mcontext.mc_ebx = regs->tf_rbx;
606	sf.sf_uc.uc_mcontext.mc_edx = regs->tf_rdx;
607	sf.sf_uc.uc_mcontext.mc_ecx = regs->tf_rcx;
608	sf.sf_uc.uc_mcontext.mc_eax = regs->tf_rax;
609	sf.sf_uc.uc_mcontext.mc_trapno = regs->tf_trapno;
610	sf.sf_uc.uc_mcontext.mc_err = regs->tf_err;
611	sf.sf_uc.uc_mcontext.mc_eip = regs->tf_rip;
612	sf.sf_uc.uc_mcontext.mc_cs = regs->tf_cs;
613	sf.sf_uc.uc_mcontext.mc_eflags = regs->tf_rflags;
614	sf.sf_uc.uc_mcontext.mc_esp = regs->tf_rsp;
615	sf.sf_uc.uc_mcontext.mc_ss = regs->tf_ss;
616	sf.sf_uc.uc_mcontext.mc_ds = regs->tf_ds;
617	sf.sf_uc.uc_mcontext.mc_es = regs->tf_es;
618	sf.sf_uc.uc_mcontext.mc_fs = regs->tf_fs;
619	sf.sf_uc.uc_mcontext.mc_gs = regs->tf_gs;
620	sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */
621	ia32_get_fpcontext(td, &sf.sf_uc.uc_mcontext, xfpusave, xfpusave_len);
622	fpstate_drop(td);
623	sf.sf_uc.uc_mcontext.mc_fsbase = td->td_pcb->pcb_fsbase;
624	sf.sf_uc.uc_mcontext.mc_gsbase = td->td_pcb->pcb_gsbase;
625	bzero(sf.sf_uc.__spare__, sizeof(sf.sf_uc.__spare__));
626
627	/* Allocate space for the signal handler context. */
628	if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
629	    SIGISMEMBER(psp->ps_sigonstack, sig))
630		sp = (char *)td->td_sigstk.ss_sp + td->td_sigstk.ss_size;
631	else
632		sp = (char *)regs->tf_rsp;
633	if (xfpusave != NULL) {
634		sp -= xfpusave_len;
635		sp = (char *)((unsigned long)sp & ~0x3Ful);
636		sf.sf_uc.uc_mcontext.mc_xfpustate = (register_t)sp;
637	}
638	sp -= sizeof(sf);
639	/* Align to 16 bytes. */
640	sfp = (struct ia32_sigframe *)((uintptr_t)sp & ~0xF);
641	PROC_UNLOCK(p);
642
643	/* Build the argument list for the signal handler. */
644	sf.sf_signum = sig;
645	sf.sf_ucontext = (register_t)&sfp->sf_uc;
646	bzero(&sf.sf_si, sizeof(sf.sf_si));
647	if (SIGISMEMBER(psp->ps_siginfo, sig)) {
648		/* Signal handler installed with SA_SIGINFO. */
649		sf.sf_siginfo = (u_int32_t)(uintptr_t)&sfp->sf_si;
650		sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
651
652		/* Fill in POSIX parts */
653		sf.sf_si = siginfo;
654		sf.sf_si.si_signo = sig;
655	} else {
656		/* Old FreeBSD-style arguments. */
657		sf.sf_siginfo = siginfo.si_code;
658		sf.sf_addr = (u_int32_t)siginfo.si_addr;
659		sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
660	}
661	mtx_unlock(&psp->ps_mtx);
662
663	/*
664	 * Copy the sigframe out to the user's stack.
665	 */
666	if (copyout(&sf, sfp, sizeof(*sfp)) != 0 ||
667	    (xfpusave != NULL && copyout(xfpusave,
668	    PTRIN(sf.sf_uc.uc_mcontext.mc_xfpustate), xfpusave_len)
669	    != 0)) {
670#ifdef DEBUG
671		printf("process %ld has trashed its stack\n", (long)p->p_pid);
672#endif
673		PROC_LOCK(p);
674		sigexit(td, SIGILL);
675	}
676
677	regs->tf_rsp = (uintptr_t)sfp;
678	regs->tf_rip = p->p_sysent->sv_sigcode_base;
679	regs->tf_rflags &= ~(PSL_T | PSL_D);
680	regs->tf_cs = _ucode32sel;
681	regs->tf_ss = _udatasel;
682	regs->tf_ds = _udatasel;
683	regs->tf_es = _udatasel;
684	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
685	/* XXXKIB leave user %fs and %gs untouched */
686	PROC_LOCK(p);
687	mtx_lock(&psp->ps_mtx);
688}
689
690/*
691 * System call to cleanup state after a signal
692 * has been taken.  Reset signal mask and
693 * stack state from context left by sendsig (above).
694 * Return to previous pc and psl as specified by
695 * context left by sendsig. Check carefully to
696 * make sure that the user has not modified the
697 * state to gain improper privileges.
698 */
699
700#ifdef COMPAT_43
701int
702ofreebsd32_sigreturn(struct thread *td, struct ofreebsd32_sigreturn_args *uap)
703{
704	struct ia32_sigcontext3 sc, *scp;
705	struct trapframe *regs;
706	int eflags, error;
707	ksiginfo_t ksi;
708
709	regs = td->td_frame;
710	error = copyin(uap->sigcntxp, &sc, sizeof(sc));
711	if (error != 0)
712		return (error);
713	scp = &sc;
714	eflags = scp->sc_eflags;
715	if (!EFL_SECURE(eflags, regs->tf_rflags)) {
716		return (EINVAL);
717	}
718	if (!CS_SECURE(scp->sc_cs)) {
719		ksiginfo_init_trap(&ksi);
720		ksi.ksi_signo = SIGBUS;
721		ksi.ksi_code = BUS_OBJERR;
722		ksi.ksi_trapno = T_PROTFLT;
723		ksi.ksi_addr = (void *)regs->tf_rip;
724		trapsignal(td, &ksi);
725		return (EINVAL);
726	}
727	regs->tf_ds = scp->sc_ds;
728	regs->tf_es = scp->sc_es;
729	regs->tf_fs = scp->sc_fs;
730	regs->tf_gs = scp->sc_gs;
731
732	regs->tf_rax = scp->sc_eax;
733	regs->tf_rbx = scp->sc_ebx;
734	regs->tf_rcx = scp->sc_ecx;
735	regs->tf_rdx = scp->sc_edx;
736	regs->tf_rsi = scp->sc_esi;
737	regs->tf_rdi = scp->sc_edi;
738	regs->tf_cs = scp->sc_cs;
739	regs->tf_ss = scp->sc_ss;
740	regs->tf_rbp = scp->sc_ebp;
741	regs->tf_rsp = scp->sc_esp;
742	regs->tf_rip = scp->sc_eip;
743	regs->tf_rflags = eflags;
744
745	if (scp->sc_onstack & 1)
746		td->td_sigstk.ss_flags |= SS_ONSTACK;
747	else
748		td->td_sigstk.ss_flags &= ~SS_ONSTACK;
749
750	kern_sigprocmask(td, SIG_SETMASK, (sigset_t *)&scp->sc_mask, NULL,
751	    SIGPROCMASK_OLD);
752	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
753	return (EJUSTRETURN);
754}
755#endif
756
757#ifdef COMPAT_FREEBSD4
758/*
759 * MPSAFE
760 */
761int
762freebsd4_freebsd32_sigreturn(td, uap)
763	struct thread *td;
764	struct freebsd4_freebsd32_sigreturn_args /* {
765		const struct freebsd4_freebsd32_ucontext *sigcntxp;
766	} */ *uap;
767{
768	struct ia32_ucontext4 uc;
769	struct trapframe *regs;
770	struct ia32_ucontext4 *ucp;
771	int cs, eflags, error;
772	ksiginfo_t ksi;
773
774	error = copyin(uap->sigcntxp, &uc, sizeof(uc));
775	if (error != 0)
776		return (error);
777	ucp = &uc;
778	regs = td->td_frame;
779	eflags = ucp->uc_mcontext.mc_eflags;
780	/*
781	 * Don't allow users to change privileged or reserved flags.
782	 */
783	if (!EFL_SECURE(eflags, regs->tf_rflags)) {
784		uprintf("pid %d (%s): freebsd4_freebsd32_sigreturn eflags = 0x%x\n",
785		    td->td_proc->p_pid, td->td_name, eflags);
786		return (EINVAL);
787	}
788
789	/*
790	 * Don't allow users to load a valid privileged %cs.  Let the
791	 * hardware check for invalid selectors, excess privilege in
792	 * other selectors, invalid %eip's and invalid %esp's.
793	 */
794	cs = ucp->uc_mcontext.mc_cs;
795	if (!CS_SECURE(cs)) {
796		uprintf("pid %d (%s): freebsd4_sigreturn cs = 0x%x\n",
797		    td->td_proc->p_pid, td->td_name, cs);
798		ksiginfo_init_trap(&ksi);
799		ksi.ksi_signo = SIGBUS;
800		ksi.ksi_code = BUS_OBJERR;
801		ksi.ksi_trapno = T_PROTFLT;
802		ksi.ksi_addr = (void *)regs->tf_rip;
803		trapsignal(td, &ksi);
804		return (EINVAL);
805	}
806
807	regs->tf_rdi = ucp->uc_mcontext.mc_edi;
808	regs->tf_rsi = ucp->uc_mcontext.mc_esi;
809	regs->tf_rbp = ucp->uc_mcontext.mc_ebp;
810	regs->tf_rbx = ucp->uc_mcontext.mc_ebx;
811	regs->tf_rdx = ucp->uc_mcontext.mc_edx;
812	regs->tf_rcx = ucp->uc_mcontext.mc_ecx;
813	regs->tf_rax = ucp->uc_mcontext.mc_eax;
814	regs->tf_trapno = ucp->uc_mcontext.mc_trapno;
815	regs->tf_err = ucp->uc_mcontext.mc_err;
816	regs->tf_rip = ucp->uc_mcontext.mc_eip;
817	regs->tf_cs = cs;
818	regs->tf_rflags = ucp->uc_mcontext.mc_eflags;
819	regs->tf_rsp = ucp->uc_mcontext.mc_esp;
820	regs->tf_ss = ucp->uc_mcontext.mc_ss;
821	regs->tf_ds = ucp->uc_mcontext.mc_ds;
822	regs->tf_es = ucp->uc_mcontext.mc_es;
823	regs->tf_fs = ucp->uc_mcontext.mc_fs;
824	regs->tf_gs = ucp->uc_mcontext.mc_gs;
825
826	kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0);
827	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
828	return (EJUSTRETURN);
829}
830#endif	/* COMPAT_FREEBSD4 */
831
832/*
833 * MPSAFE
834 */
835int
836freebsd32_sigreturn(td, uap)
837	struct thread *td;
838	struct freebsd32_sigreturn_args /* {
839		const struct freebsd32_ucontext *sigcntxp;
840	} */ *uap;
841{
842	struct ia32_ucontext uc;
843	struct trapframe *regs;
844	struct ia32_ucontext *ucp;
845	char *xfpustate;
846	size_t xfpustate_len;
847	int cs, eflags, error, ret;
848	ksiginfo_t ksi;
849
850	error = copyin(uap->sigcntxp, &uc, sizeof(uc));
851	if (error != 0)
852		return (error);
853	ucp = &uc;
854	regs = td->td_frame;
855	eflags = ucp->uc_mcontext.mc_eflags;
856	/*
857	 * Don't allow users to change privileged or reserved flags.
858	 */
859	if (!EFL_SECURE(eflags, regs->tf_rflags)) {
860		uprintf("pid %d (%s): freebsd32_sigreturn eflags = 0x%x\n",
861		    td->td_proc->p_pid, td->td_name, eflags);
862		return (EINVAL);
863	}
864
865	/*
866	 * Don't allow users to load a valid privileged %cs.  Let the
867	 * hardware check for invalid selectors, excess privilege in
868	 * other selectors, invalid %eip's and invalid %esp's.
869	 */
870	cs = ucp->uc_mcontext.mc_cs;
871	if (!CS_SECURE(cs)) {
872		uprintf("pid %d (%s): sigreturn cs = 0x%x\n",
873		    td->td_proc->p_pid, td->td_name, cs);
874		ksiginfo_init_trap(&ksi);
875		ksi.ksi_signo = SIGBUS;
876		ksi.ksi_code = BUS_OBJERR;
877		ksi.ksi_trapno = T_PROTFLT;
878		ksi.ksi_addr = (void *)regs->tf_rip;
879		trapsignal(td, &ksi);
880		return (EINVAL);
881	}
882
883	if ((ucp->uc_mcontext.mc_flags & _MC_HASFPXSTATE) != 0) {
884		xfpustate_len = uc.uc_mcontext.mc_xfpustate_len;
885		if (xfpustate_len > cpu_max_ext_state_size -
886		    sizeof(struct savefpu)) {
887			uprintf("pid %d (%s): sigreturn xfpusave_len = 0x%zx\n",
888			    td->td_proc->p_pid, td->td_name, xfpustate_len);
889			return (EINVAL);
890		}
891		xfpustate = __builtin_alloca(xfpustate_len);
892		error = copyin(PTRIN(ucp->uc_mcontext.mc_xfpustate),
893		    xfpustate, xfpustate_len);
894		if (error != 0) {
895			uprintf(
896	"pid %d (%s): sigreturn copying xfpustate failed\n",
897			    td->td_proc->p_pid, td->td_name);
898			return (error);
899		}
900	} else {
901		xfpustate = NULL;
902		xfpustate_len = 0;
903	}
904	ret = ia32_set_fpcontext(td, &ucp->uc_mcontext, xfpustate,
905	    xfpustate_len);
906	if (ret != 0) {
907		uprintf("pid %d (%s): sigreturn set_fpcontext err %d\n",
908		    td->td_proc->p_pid, td->td_name, ret);
909		return (ret);
910	}
911
912	regs->tf_rdi = ucp->uc_mcontext.mc_edi;
913	regs->tf_rsi = ucp->uc_mcontext.mc_esi;
914	regs->tf_rbp = ucp->uc_mcontext.mc_ebp;
915	regs->tf_rbx = ucp->uc_mcontext.mc_ebx;
916	regs->tf_rdx = ucp->uc_mcontext.mc_edx;
917	regs->tf_rcx = ucp->uc_mcontext.mc_ecx;
918	regs->tf_rax = ucp->uc_mcontext.mc_eax;
919	regs->tf_trapno = ucp->uc_mcontext.mc_trapno;
920	regs->tf_err = ucp->uc_mcontext.mc_err;
921	regs->tf_rip = ucp->uc_mcontext.mc_eip;
922	regs->tf_cs = cs;
923	regs->tf_rflags = ucp->uc_mcontext.mc_eflags;
924	regs->tf_rsp = ucp->uc_mcontext.mc_esp;
925	regs->tf_ss = ucp->uc_mcontext.mc_ss;
926	regs->tf_ds = ucp->uc_mcontext.mc_ds;
927	regs->tf_es = ucp->uc_mcontext.mc_es;
928	regs->tf_fs = ucp->uc_mcontext.mc_fs;
929	regs->tf_gs = ucp->uc_mcontext.mc_gs;
930	regs->tf_flags = TF_HASSEGS;
931
932	kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0);
933	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
934	return (EJUSTRETURN);
935}
936
937/*
938 * Clear registers on exec
939 */
940void
941ia32_setregs(struct thread *td, struct image_params *imgp, u_long stack)
942{
943	struct trapframe *regs;
944	struct pcb *pcb;
945	register_t saved_rflags;
946
947	regs = td->td_frame;
948	pcb = td->td_pcb;
949
950	if (td->td_proc->p_md.md_ldt != NULL)
951		user_ldt_free(td);
952#ifdef COMPAT_43
953	setup_lcall_gate();
954#endif
955
956	pcb->pcb_fsbase = 0;
957	pcb->pcb_gsbase = 0;
958	pcb->pcb_initial_fpucw = __INITIAL_FPUCW_I386__;
959
960	saved_rflags = regs->tf_rflags & PSL_T;
961	bzero((char *)regs, sizeof(struct trapframe));
962	regs->tf_rip = imgp->entry_addr;
963	regs->tf_rsp = stack;
964	regs->tf_rflags = PSL_USER | saved_rflags;
965	regs->tf_ss = _udatasel;
966	regs->tf_cs = _ucode32sel;
967	regs->tf_rbx = imgp->ps_strings;
968	regs->tf_ds = _udatasel;
969	regs->tf_es = _udatasel;
970	regs->tf_fs = _ufssel;
971	regs->tf_gs = _ugssel;
972	regs->tf_flags = TF_HASSEGS;
973
974	x86_clear_dbregs(pcb);
975
976	fpstate_drop(td);
977
978	/* Return via doreti so that we can change to a different %cs */
979	set_pcb_flags(pcb, PCB_32BIT | PCB_FULL_IRET);
980}
981