1 /*	$NetBSD: linux32_machdep.c,v 1.35 2014/02/15 10:11:15 dsl Exp $ */
2 
3 /*-
4  * Copyright (c) 2006 Emmanuel Dreyfus, all rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Emmanuel Dreyfus
17  * 4. The name of the author may not be used to endorse or promote
18  *    products derived from this software without specific prior written
19  *    permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE THE AUTHOR AND CONTRIBUTORS ``AS IS''
22  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: linux32_machdep.c,v 1.35 2014/02/15 10:11:15 dsl Exp $");
35 
36 #include <sys/param.h>
37 #include <sys/proc.h>
38 #include <sys/exec.h>
39 
40 #include <machine/vmparam.h>
41 #include <machine/cpufunc.h>
42 #include <machine/netbsd32_machdep.h>
43 
44 #include <compat/netbsd32/netbsd32.h>
45 #include <compat/netbsd32/netbsd32_syscallargs.h>
46 
47 #include <compat/linux/common/linux_types.h>
48 #include <compat/linux/common/linux_emuldata.h>
49 #include <compat/linux/common/linux_signal.h>
50 #include <compat/linux/common/linux_errno.h>
51 #include <compat/linux/common/linux_exec.h>
52 #include <compat/linux/common/linux_ipc.h>
53 #include <compat/linux/common/linux_sem.h>
54 #include <compat/linux/linux_syscallargs.h>
55 
56 #include <compat/linux32/common/linux32_types.h>
57 #include <compat/linux32/common/linux32_errno.h>
58 #include <compat/linux32/common/linux32_machdep.h>
59 #include <compat/linux32/common/linux32_signal.h>
60 #include <compat/linux32/common/linux32_exec.h>
61 #include <compat/linux32/common/linux32_ipc.h>
62 #include <compat/linux32/common/linux32_sem.h>
63 #include <compat/linux32/linux32_syscallargs.h>
64 
65 #ifdef DEBUG_LINUX
66 #define DPRINTF(a) uprintf a
67 #else
68 #define DPRINTF(a)
69 #endif
70 
71 extern char linux32_sigcode[];
72 extern char linux32_rt_sigcode[];
73 extern char linux32_esigcode[];
74 
75 static void linux32_save_ucontext(struct lwp *, struct trapframe *,
76     const sigset_t *, struct sigaltstack *, struct linux32_ucontext *);
77 static void linux32_save_sigcontext(struct lwp *, struct trapframe *,
78     const sigset_t *, struct linux32_sigcontext *);
79 static void linux32_rt_sendsig(const ksiginfo_t *, const sigset_t *);
80 static void linux32_old_sendsig(const ksiginfo_t *, const sigset_t *);
81 static int linux32_restore_sigcontext(struct lwp *,
82     struct linux32_sigcontext *, register_t *);
83 
84 void
85 linux32_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
86 {
87 	if (SIGACTION(curproc, ksi->ksi_signo).sa_flags & SA_SIGINFO)
88 		linux32_rt_sendsig(ksi, mask);
89 	else
90 		linux32_old_sendsig(ksi, mask);
91 	return;
92 }
93 
94 void
95 linux32_old_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
96 {
97 	struct lwp *l = curlwp;
98 	struct proc *p = l->l_proc;
99 	struct trapframe *tf;
100 	struct linux32_sigframe *fp, frame;
101 	int onstack, error;
102 	int sig = ksi->ksi_signo;
103 	sig_t catcher = SIGACTION(p, sig).sa_handler;
104 	struct sigaltstack *sas = &l->l_sigstk;
105 
106 	tf = l->l_md.md_regs;
107 	/* Do we need to jump onto the signal stack? */
108 	onstack = (sas->ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
109 	    (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
110 
111 
112 	/* Allocate space for the signal handler context. */
113 	if (onstack)
114 		fp = (struct linux32_sigframe *)((char *)sas->ss_sp +
115 		    sas->ss_size);
116 	else
117 		fp = (struct linux32_sigframe *)tf->tf_rsp;
118 	fp--;
119 
120 	DPRINTF(("old: onstack = %d, fp = %p sig = %d rip = 0x%lx\n",
121 	    onstack, fp, sig, tf->tf_rip));
122 
123 	/* Build stack frame for signal trampoline. */
124 	NETBSD32PTR32(frame.sf_handler, catcher);
125 	frame.sf_sig = native_to_linux32_signo[sig];
126 
127 	linux32_save_sigcontext(l, tf, mask, &frame.sf_sc);
128 
129 	sendsig_reset(l, sig);
130 	mutex_exit(p->p_lock);
131 	error = copyout(&frame, fp, sizeof(frame));
132 	mutex_enter(p->p_lock);
133 
134 	if (error != 0) {
135 		/*
136 		 * Process has trashed its stack; give it an illegal
137 		 * instruction to halt it in its tracks.
138 		 */
139 		sigexit(l, SIGILL);
140 		/* NOTREACHED */
141 	}
142 
143 	/*
144 	 * Build context to run handler in.
145 	 */
146 	tf->tf_fs = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
147 	tf->tf_es = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
148 	tf->tf_ds = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
149 	tf->tf_rip = ((long)p->p_sigctx.ps_sigcode) & 0xffffffff;
150 	tf->tf_cs = GSEL(GUCODE32_SEL, SEL_UPL) & 0xffffffff;
151 	tf->tf_rflags &= ~PSL_CLEARSIG & 0xffffffff;
152 	tf->tf_rsp = (long)fp & 0xffffffff;
153 	tf->tf_ss = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
154 
155 	/* Remember that we're now on the signal stack. */
156 	if (onstack)
157 		sas->ss_flags |= SS_ONSTACK;
158 
159 	return;
160 }
161 
162 void
163 linux32_rt_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
164 {
165 	struct lwp *l = curlwp;
166 	struct proc *p = l->l_proc;
167 	struct trapframe *tf;
168 	struct linux32_rt_sigframe *fp, frame;
169 	int onstack, error;
170 	linux32_siginfo_t *lsi;
171 	int sig = ksi->ksi_signo;
172 	sig_t catcher = SIGACTION(p, sig).sa_handler;
173 	struct sigaltstack *sas = &l->l_sigstk;
174 
175 	tf = l->l_md.md_regs;
176 	/* Do we need to jump onto the signal stack? */
177 	onstack = (sas->ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
178 	    (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
179 
180 
181 	/* Allocate space for the signal handler context. */
182 	if (onstack)
183 		fp = (struct linux32_rt_sigframe *)((char *)sas->ss_sp +
184 		    sas->ss_size);
185 	else
186 		fp = (struct linux32_rt_sigframe *)tf->tf_rsp;
187 	fp--;
188 
189 	/* Build stack frame for signal trampoline. */
190 	NETBSD32PTR32(frame.sf_handler, catcher);
191 	frame.sf_sig = native_to_linux32_signo[sig];
192 	NETBSD32PTR32(frame.sf_sip, &fp->sf_si);
193 	NETBSD32PTR32(frame.sf_ucp, &fp->sf_uc);
194 
195 	DPRINTF(("rt: onstack = %d, fp = %p sig = %d rip = 0x%lx\n",
196 	    onstack, fp, sig, tf->tf_rip));
197 
198 	lsi = &frame.sf_si;
199 	(void)memset(lsi, 0, sizeof(frame.sf_si));
200 	lsi->lsi_errno = native_to_linux32_errno[ksi->ksi_errno];
201 	lsi->lsi_code = native_to_linux_si_code(ksi->ksi_code);
202 	lsi->lsi_signo = frame.sf_sig;
203 	switch (lsi->lsi_signo) {
204 	case LINUX32_SIGILL:
205 	case LINUX32_SIGFPE:
206 	case LINUX32_SIGSEGV:
207 	case LINUX32_SIGBUS:
208 	case LINUX32_SIGTRAP:
209 		NETBSD32PTR32(lsi->lsi_addr, ksi->ksi_addr);
210 		break;
211 	case LINUX32_SIGCHLD:
212 		lsi->lsi_uid = ksi->ksi_uid;
213 		lsi->lsi_pid = ksi->ksi_pid;
214 		lsi->lsi_utime = ksi->ksi_utime;
215 		lsi->lsi_stime = ksi->ksi_stime;
216 		lsi->lsi_status = native_to_linux_si_status(ksi->ksi_code,
217 		    ksi->ksi_status);
218 		break;
219 	case LINUX32_SIGIO:
220 		lsi->lsi_band = ksi->ksi_band;
221 		lsi->lsi_fd = ksi->ksi_fd;
222 		break;
223 	default:
224 		lsi->lsi_uid = ksi->ksi_uid;
225 		lsi->lsi_pid = ksi->ksi_pid;
226 		if (lsi->lsi_signo == LINUX32_SIGALRM ||
227 		    lsi->lsi_signo >= LINUX32_SIGRTMIN)
228 			NETBSD32PTR32(lsi->lsi_value.sival_ptr,
229 			     ksi->ksi_value.sival_ptr);
230 		break;
231 	}
232 
233 	/* Save register context. */
234 	linux32_save_ucontext(l, tf, mask, sas, &frame.sf_uc);
235 	sendsig_reset(l, sig);
236 	mutex_exit(p->p_lock);
237 	error = copyout(&frame, fp, sizeof(frame));
238 	mutex_enter(p->p_lock);
239 
240 	if (error != 0) {
241 		/*
242 		 * Process has trashed its stack; give it an illegal
243 		 * instruction to halt it in its tracks.
244 		 */
245 		sigexit(l, SIGILL);
246 		/* NOTREACHED */
247 	}
248 
249 	/*
250 	 * Build context to run handler in.
251 	 */
252 	tf->tf_fs = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
253 	tf->tf_es = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
254 	tf->tf_ds = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
255 	tf->tf_rip = (((long)p->p_sigctx.ps_sigcode) +
256 	    (linux32_rt_sigcode - linux32_sigcode)) & 0xffffffff;
257 	tf->tf_cs = GSEL(GUCODE32_SEL, SEL_UPL) & 0xffffffff;
258 	tf->tf_rflags &= ~PSL_CLEARSIG & 0xffffffff;
259 	tf->tf_rsp = (long)fp & 0xffffffff;
260 	tf->tf_ss = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
261 
262 	/* Remember that we're now on the signal stack. */
263 	if (onstack)
264 		sas->ss_flags |= SS_ONSTACK;
265 
266 	return;
267 }
268 
269 void
270 linux32_setregs(struct lwp *l, struct exec_package *pack, u_long stack)
271 {
272 	struct pcb *pcb = lwp_getpcb(l);
273 	struct trapframe *tf;
274 	struct proc *p = l->l_proc;
275 
276 #if defined(USER_LDT) && 0
277 	pmap_ldt_cleanup(p);
278 #endif
279 
280 	netbsd32_adjust_limits(p);
281 
282 	fpu_save_area_clear(l, __Linux_NPXCW__);
283 
284 	l->l_md.md_flags |= MDL_COMPAT32;	/* Forces iret not sysret */
285 	pcb->pcb_flags = PCB_COMPAT32;
286 
287 	p->p_flag |= PK_32;
288 
289 	tf = l->l_md.md_regs;
290 	tf->tf_rax = 0;
291 	tf->tf_rbx = (u_int32_t)p->p_psstrp;
292 	tf->tf_rcx = pack->ep_entry & 0xffffffff;
293 	tf->tf_rdx = 0;
294 	tf->tf_rsi = 0;
295 	tf->tf_rdi = 0;
296 	tf->tf_rbp = 0;
297 	tf->tf_rsp = stack & 0xffffffff;
298 	tf->tf_r8 = 0;
299 	tf->tf_r9 = 0;
300 	tf->tf_r10 = 0;
301 	tf->tf_r11 = 0;
302 	tf->tf_r12 = 0;
303 	tf->tf_r13 = 0;
304 	tf->tf_r14 = 0;
305 	tf->tf_r15 = 0;
306 	tf->tf_rip = pack->ep_entry & 0xffffffff;
307 	tf->tf_rflags = PSL_USERSET;
308 	tf->tf_cs = GSEL(GUCODE32_SEL, SEL_UPL);
309 	tf->tf_ss = GSEL(GUDATA32_SEL, SEL_UPL);
310 	tf->tf_ds = GSEL(GUDATA32_SEL, SEL_UPL);
311 	tf->tf_es = GSEL(GUDATA32_SEL, SEL_UPL);
312 	cpu_fsgs_zero(l);
313 	cpu_fsgs_reload(l, GSEL(GUDATA32_SEL, SEL_UPL), GSEL(GUDATA32_SEL, SEL_UPL));
314 }
315 
316 static void
317 linux32_save_ucontext(struct lwp *l, struct trapframe *tf,
318     const sigset_t *mask, struct sigaltstack *sas, struct linux32_ucontext *uc)
319 {
320 
321 	uc->uc_flags = 0;
322 	NETBSD32PTR32(uc->uc_link, NULL);
323 	native_to_linux32_sigaltstack(&uc->uc_stack, sas);
324 	linux32_save_sigcontext(l, tf, mask, &uc->uc_mcontext);
325 	native_to_linux32_sigset(&uc->uc_sigmask, mask);
326 	(void)memset(&uc->uc_fpregs_mem, 0, sizeof(uc->uc_fpregs_mem));
327 }
328 
329 static void
330 linux32_save_sigcontext(struct lwp *l, struct trapframe *tf,
331 			const sigset_t *mask, struct linux32_sigcontext *sc)
332 {
333 	struct pcb *pcb = lwp_getpcb(l);
334 
335 	/* Save register context. */
336 	sc->sc_gs = tf->tf_gs;
337 	sc->sc_fs = tf->tf_fs;
338 	sc->sc_es = tf->tf_es;
339 	sc->sc_ds = tf->tf_ds;
340 	sc->sc_eflags = tf->tf_rflags;
341 	sc->sc_edi = tf->tf_rdi;
342 	sc->sc_esi = tf->tf_rsi;
343 	sc->sc_esp = tf->tf_rsp;
344 	sc->sc_ebp = tf->tf_rbp;
345 	sc->sc_ebx = tf->tf_rbx;
346 	sc->sc_edx = tf->tf_rdx;
347 	sc->sc_ecx = tf->tf_rcx;
348 	sc->sc_eax = tf->tf_rax;
349 	sc->sc_eip = tf->tf_rip;
350 	sc->sc_cs = tf->tf_cs;
351 	sc->sc_esp_at_signal = tf->tf_rsp;
352 	sc->sc_ss = tf->tf_ss;
353 	sc->sc_err = tf->tf_err;
354 	sc->sc_trapno = tf->tf_trapno;
355 	sc->sc_cr2 = pcb->pcb_cr2;
356 	NETBSD32PTR32(sc->sc_387, NULL);
357 
358 	/* Save signal stack. */
359 	/* Linux doesn't save the onstack flag in sigframe */
360 
361 	/* Save signal mask. */
362 	native_to_linux32_old_sigset(&sc->sc_mask, mask);
363 }
364 
365 int
366 linux32_sys_sigreturn(struct lwp *l,
367     const struct linux32_sys_sigreturn_args *uap, register_t *retval)
368 {
369 	/* {
370 		syscallarg(linux32_sigcontextp_t) scp;
371 	} */
372 	struct linux32_sigcontext ctx;
373 	int error;
374 
375 	if ((error = copyin(SCARG_P32(uap, scp), &ctx, sizeof(ctx))) != 0)
376 		return error;
377 
378 	return linux32_restore_sigcontext(l, &ctx, retval);
379 }
380 
381 int
382 linux32_sys_rt_sigreturn(struct lwp *l,
383     const struct linux32_sys_rt_sigreturn_args *uap, register_t *retval)
384 {
385 	/* {
386 		syscallarg(linux32_ucontextp_t) ucp;
387 	} */
388 	struct linux32_ucontext ctx;
389 	int error;
390 
391 	if ((error = copyin(SCARG_P32(uap, ucp), &ctx, sizeof(ctx))) != 0)
392 		return error;
393 
394 	return linux32_restore_sigcontext(l, &ctx.uc_mcontext, retval);
395 }
396 
397 static int
398 linux32_restore_sigcontext(struct lwp *l, struct linux32_sigcontext *scp,
399 			register_t *retval)
400 {
401 	struct trapframe *tf;
402 	struct proc *p = l->l_proc;
403 	struct sigaltstack *sas = &l->l_sigstk;
404 	struct pcb *pcb;
405 	sigset_t mask;
406 	ssize_t ss_gap;
407 	register_t fssel, gssel;
408 
409 	/* Restore register context. */
410 	tf = l->l_md.md_regs;
411 	pcb = lwp_getpcb(l);
412 	DPRINTF(("sigreturn enter rsp=0x%lx rip=0x%lx\n", tf->tf_rsp,
413 		 tf->tf_rip));
414 
415 	/*
416 	 * Check for security violations.
417 	 */
418 	if (((scp->sc_eflags ^ tf->tf_rflags) & PSL_USERSTATIC) != 0 ||
419 	    !USERMODE(scp->sc_cs, scp->sc_eflags))
420 		return EINVAL;
421 
422 	if (scp->sc_fs != 0 && !VALID_USER_DSEL32(scp->sc_fs) &&
423 	    !(VALID_USER_FSEL32(scp->sc_fs) && pcb->pcb_fs != 0))
424 		return EINVAL;
425 
426 	if (scp->sc_gs != 0 && !VALID_USER_DSEL32(scp->sc_gs) &&
427 	    !(VALID_USER_GSEL32(scp->sc_gs) && pcb->pcb_gs != 0))
428 		return EINVAL;
429 
430 	if (scp->sc_es != 0 && !VALID_USER_DSEL32(scp->sc_es))
431 		return EINVAL;
432 
433 	if (!VALID_USER_DSEL32(scp->sc_ds) ||
434 	    !VALID_USER_DSEL32(scp->sc_ss))
435 		return EINVAL;
436 
437 	if (scp->sc_eip >= VM_MAXUSER_ADDRESS32)
438 		return EINVAL;
439 
440 	gssel = (register_t)scp->sc_gs & 0xffff;
441 	fssel = (register_t)scp->sc_fs & 0xffff;
442 	cpu_fsgs_reload(l, fssel, gssel);
443 	tf->tf_es = (register_t)scp->sc_es & 0xffff;
444 	tf->tf_ds = (register_t)scp->sc_ds & 0xffff;
445 	tf->tf_rflags &= ~PSL_USER;
446 	tf->tf_rflags |= ((register_t)scp->sc_eflags & PSL_USER);
447 	tf->tf_rdi = (register_t)scp->sc_edi & 0xffffffff;
448 	tf->tf_rsi = (register_t)scp->sc_esi & 0xffffffff;
449 	tf->tf_rbp = (register_t)scp->sc_ebp & 0xffffffff;
450 	tf->tf_rbx = (register_t)scp->sc_ebx & 0xffffffff;
451 	tf->tf_rdx = (register_t)scp->sc_edx & 0xffffffff;
452 	tf->tf_rcx = (register_t)scp->sc_ecx & 0xffffffff;
453 	tf->tf_rax = (register_t)scp->sc_eax & 0xffffffff;
454 	tf->tf_rip = (register_t)scp->sc_eip & 0xffffffff;
455 	tf->tf_cs = (register_t)scp->sc_cs & 0xffff;
456 	tf->tf_rsp = (register_t)scp->sc_esp_at_signal & 0xffffffff;
457 	tf->tf_ss = (register_t)scp->sc_ss & 0xffff;
458 
459 	mutex_enter(p->p_lock);
460 
461 	/* Restore signal stack. */
462 	ss_gap = (ssize_t)
463 	    ((char *)NETBSD32IPTR64(scp->sc_esp_at_signal)
464 	     - (char *)sas->ss_sp);
465 	if (ss_gap >= 0 && ss_gap < sas->ss_size)
466 		sas->ss_flags |= SS_ONSTACK;
467 	else
468 		sas->ss_flags &= ~SS_ONSTACK;
469 
470 	/* Restore signal mask. */
471 	linux32_old_to_native_sigset(&mask, &scp->sc_mask);
472 	(void) sigprocmask1(l, SIG_SETMASK, &mask, 0);
473 
474 	mutex_exit(p->p_lock);
475 
476 	DPRINTF(("linux32_sigreturn: rip = 0x%lx, rsp = 0x%lx, flags = 0x%lx\n",
477 	    tf->tf_rip, tf->tf_rsp, tf->tf_rflags));
478 	return EJUSTRETURN;
479 }
480 
481 int
482 linux32_sys_set_thread_area(struct lwp *l,
483     const struct linux32_sys_set_thread_area_args *uap, register_t *retval)
484 {
485 	/* {
486 		syscallarg(linux32_user_descp_t) desc;
487 	} */
488 
489 	return linux_lwp_setprivate(l, SCARG_P32(uap, desc));
490 }
491 
492 int
493 linux32_sys_get_thread_area(struct lwp *l,
494     const struct linux32_sys_get_thread_area_args *uap, register_t *retval)
495 {
496 	/* {
497 		syscallarg(linux32_user_descp_t) desc;
498 	} */
499 
500 	/* glibc doesn't actually call this. */
501 	return ENOSYS;
502 }
503 
504 int
505 linux32_sys_modify_ldt(struct lwp *l, const struct linux32_sys_modify_ldt_args *uap, register_t *retval)
506 {
507 	/* {
508 		syscallarg(int) func;
509 		syscallarg(netbsd32_charp) ptr;
510 		syscallarg(netbsd32_size_t) bytecount;
511 	} */
512 	struct linux_sys_modify_ldt_args ua;
513 
514 	NETBSD32TO64_UAP(func);
515 	NETBSD32TOP_UAP(ptr, void *);
516 	NETBSD32TOX_UAP(bytecount, size_t);
517 	return linux_sys_modify_ldt(l, &ua, retval);
518 }
519