1 /*	$NetBSD: linux32_machdep.c,v 1.48 2023/06/20 15:22:15 riastradh 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 1.48 2023/06/20 15:22:15 riastradh Exp $");
35 
36 #if defined(_KERNEL_OPT)
37 #include "opt_user_ldt.h"
38 #endif
39 
40 #include <sys/param.h>
41 #include <sys/proc.h>
42 #include <sys/exec.h>
43 
44 #include <machine/vmparam.h>
45 #include <machine/cpufunc.h>
46 #include <machine/netbsd32_machdep.h>
47 
48 #include <x86/fpu.h>
49 
50 #include <compat/netbsd32/netbsd32.h>
51 #include <compat/netbsd32/netbsd32_syscallargs.h>
52 
53 #include <compat/linux/common/linux_types.h>
54 #include <compat/linux/common/linux_emuldata.h>
55 #include <compat/linux/common/linux_signal.h>
56 #include <compat/linux/common/linux_errno.h>
57 #include <compat/linux/common/linux_exec.h>
58 #include <compat/linux/common/linux_ipc.h>
59 #include <compat/linux/common/linux_sem.h>
60 #include <compat/linux/linux_syscallargs.h>
61 
62 #include <compat/linux32/common/linux32_types.h>
63 #include <compat/linux32/common/linux32_errno.h>
64 #include <compat/linux32/common/linux32_machdep.h>
65 #include <compat/linux32/common/linux32_signal.h>
66 #include <compat/linux32/common/linux32_exec.h>
67 #include <compat/linux32/common/linux32_ipc.h>
68 #include <compat/linux32/common/linux32_sem.h>
69 #include <compat/linux32/linux32_syscallargs.h>
70 
71 #ifdef DEBUG_LINUX
72 #define DPRINTF(a) uprintf a
73 #else
74 #define DPRINTF(a)
75 #endif
76 
77 extern char linux32_sigcode[];
78 extern char linux32_rt_sigcode[];
79 extern char linux32_esigcode[];
80 
81 static void linux32_save_ucontext(struct lwp *, struct trapframe *,
82     const sigset_t *, stack_t *, struct linux32_ucontext *);
83 static void linux32_save_sigcontext(struct lwp *, struct trapframe *,
84     const sigset_t *, struct linux32_sigcontext *);
85 static void linux32_rt_sendsig(const ksiginfo_t *, const sigset_t *);
86 static void linux32_old_sendsig(const ksiginfo_t *, const sigset_t *);
87 static int linux32_restore_sigcontext(struct lwp *,
88     struct linux32_sigcontext *, register_t *);
89 
90 void
linux32_sendsig(const ksiginfo_t * ksi,const sigset_t * mask)91 linux32_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
92 {
93 	if (SIGACTION(curproc, ksi->ksi_signo).sa_flags & SA_SIGINFO)
94 		linux32_rt_sendsig(ksi, mask);
95 	else
96 		linux32_old_sendsig(ksi, mask);
97 	return;
98 }
99 
100 void
linux32_old_sendsig(const ksiginfo_t * ksi,const sigset_t * mask)101 linux32_old_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
102 {
103 	struct lwp *l = curlwp;
104 	struct proc *p = l->l_proc;
105 	struct trapframe *tf;
106 	struct linux32_sigframe *fp, frame;
107 	int onstack, error;
108 	int sig = ksi->ksi_signo;
109 	sig_t catcher = SIGACTION(p, sig).sa_handler;
110 	stack_t *sas = &l->l_sigstk;
111 
112 	tf = l->l_md.md_regs;
113 	/* Do we need to jump onto the signal stack? */
114 	onstack = (sas->ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
115 	    (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
116 
117 
118 	/* Allocate space for the signal handler context. */
119 	if (onstack)
120 		fp = (struct linux32_sigframe *)((char *)sas->ss_sp +
121 		    sas->ss_size);
122 	else
123 		fp = (struct linux32_sigframe *)tf->tf_rsp;
124 	fp--;
125 
126 	DPRINTF(("old: onstack = %d, fp = %p sig = %d rip = 0x%lx\n",
127 	    onstack, fp, sig, tf->tf_rip));
128 
129 	memset(&frame, 0, sizeof(frame));
130 
131 	/* Build stack frame for signal trampoline. */
132 	NETBSD32PTR32(frame.sf_handler, catcher);
133 	frame.sf_sig = native_to_linux32_signo[sig];
134 
135 	linux32_save_sigcontext(l, tf, mask, &frame.sf_sc);
136 
137 	sendsig_reset(l, sig);
138 	mutex_exit(p->p_lock);
139 	error = copyout(&frame, fp, sizeof(frame));
140 	mutex_enter(p->p_lock);
141 
142 	if (error != 0) {
143 		/*
144 		 * Process has trashed its stack; give it an illegal
145 		 * instruction to halt it in its tracks.
146 		 */
147 		sigexit(l, SIGILL);
148 		/* NOTREACHED */
149 	}
150 
151 	/*
152 	 * Build context to run handler in.
153 	 */
154 	tf->tf_fs = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
155 	tf->tf_es = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
156 	tf->tf_ds = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
157 	tf->tf_rip = ((long)p->p_sigctx.ps_sigcode) & 0xffffffff;
158 	tf->tf_cs = GSEL(GUCODE32_SEL, SEL_UPL) & 0xffffffff;
159 	tf->tf_rflags &= ~PSL_CLEARSIG & 0xffffffff;
160 	tf->tf_rsp = (long)fp & 0xffffffff;
161 	tf->tf_ss = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
162 
163 	/* Remember that we're now on the signal stack. */
164 	if (onstack)
165 		sas->ss_flags |= SS_ONSTACK;
166 
167 	return;
168 }
169 
170 void
linux32_rt_sendsig(const ksiginfo_t * ksi,const sigset_t * mask)171 linux32_rt_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
172 {
173 	struct lwp *l = curlwp;
174 	struct proc *p = l->l_proc;
175 	struct trapframe *tf;
176 	struct linux32_rt_sigframe *fp, frame;
177 	int onstack, error;
178 	linux32_siginfo_t *lsi;
179 	int sig = ksi->ksi_signo;
180 	sig_t catcher = SIGACTION(p, sig).sa_handler;
181 	stack_t *sas = &l->l_sigstk;
182 
183 	tf = l->l_md.md_regs;
184 	/* Do we need to jump onto the signal stack? */
185 	onstack = (sas->ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
186 	    (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
187 
188 
189 	/* Allocate space for the signal handler context. */
190 	if (onstack)
191 		fp = (struct linux32_rt_sigframe *)((char *)sas->ss_sp +
192 		    sas->ss_size);
193 	else
194 		fp = (struct linux32_rt_sigframe *)tf->tf_rsp;
195 	fp--;
196 
197 	/* Build stack frame for signal trampoline. */
198 	memset(&frame, 0, sizeof(frame));
199 	NETBSD32PTR32(frame.sf_handler, catcher);
200 	frame.sf_sig = native_to_linux32_signo[sig];
201 	NETBSD32PTR32(frame.sf_sip, &fp->sf_si);
202 	NETBSD32PTR32(frame.sf_ucp, &fp->sf_uc);
203 
204 	DPRINTF(("rt: onstack = %d, fp = %p sig = %d rip = 0x%lx\n",
205 	    onstack, fp, sig, tf->tf_rip));
206 
207 	lsi = &frame.sf_si;
208 	(void)memset(lsi, 0, sizeof(frame.sf_si));
209 	lsi->lsi_errno = native_to_linux32_errno[ksi->ksi_errno];
210 	lsi->lsi_code = native_to_linux_si_code(ksi->ksi_code);
211 	lsi->lsi_signo = frame.sf_sig;
212 	switch (lsi->lsi_signo) {
213 	case LINUX32_SIGILL:
214 	case LINUX32_SIGFPE:
215 	case LINUX32_SIGSEGV:
216 	case LINUX32_SIGBUS:
217 	case LINUX32_SIGTRAP:
218 		NETBSD32PTR32(lsi->lsi_addr, ksi->ksi_addr);
219 		break;
220 	case LINUX32_SIGCHLD:
221 		lsi->lsi_uid = ksi->ksi_uid;
222 		lsi->lsi_pid = ksi->ksi_pid;
223 		lsi->lsi_utime = ksi->ksi_utime;
224 		lsi->lsi_stime = ksi->ksi_stime;
225 		lsi->lsi_status = native_to_linux_si_status(ksi->ksi_code,
226 		    ksi->ksi_status);
227 		break;
228 	case LINUX32_SIGIO:
229 		lsi->lsi_band = ksi->ksi_band;
230 		lsi->lsi_fd = ksi->ksi_fd;
231 		break;
232 	default:
233 		lsi->lsi_uid = ksi->ksi_uid;
234 		lsi->lsi_pid = ksi->ksi_pid;
235 		if (lsi->lsi_signo == LINUX32_SIGALRM ||
236 		    lsi->lsi_signo >= LINUX32_SIGRTMIN)
237 			NETBSD32PTR32(lsi->lsi_value.sival_ptr,
238 			     ksi->ksi_value.sival_ptr);
239 		break;
240 	}
241 
242 	/* Save register context. */
243 	linux32_save_ucontext(l, tf, mask, sas, &frame.sf_uc);
244 	sendsig_reset(l, sig);
245 	mutex_exit(p->p_lock);
246 	error = copyout(&frame, fp, sizeof(frame));
247 	mutex_enter(p->p_lock);
248 
249 	if (error != 0) {
250 		/*
251 		 * Process has trashed its stack; give it an illegal
252 		 * instruction to halt it in its tracks.
253 		 */
254 		sigexit(l, SIGILL);
255 		/* NOTREACHED */
256 	}
257 
258 	/*
259 	 * Build context to run handler in.
260 	 */
261 	tf->tf_fs = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
262 	tf->tf_es = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
263 	tf->tf_ds = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
264 	tf->tf_rip = (((long)p->p_sigctx.ps_sigcode) +
265 	    (linux32_rt_sigcode - linux32_sigcode)) & 0xffffffff;
266 	tf->tf_cs = GSEL(GUCODE32_SEL, SEL_UPL) & 0xffffffff;
267 	tf->tf_rflags &= ~PSL_CLEARSIG & 0xffffffff;
268 	tf->tf_rsp = (long)fp & 0xffffffff;
269 	tf->tf_ss = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff;
270 
271 	/* Remember that we're now on the signal stack. */
272 	if (onstack)
273 		sas->ss_flags |= SS_ONSTACK;
274 
275 	return;
276 }
277 
278 void
linux32_setregs(struct lwp * l,struct exec_package * pack,u_long stack)279 linux32_setregs(struct lwp *l, struct exec_package *pack, u_long stack)
280 {
281 	struct pcb *pcb = lwp_getpcb(l);
282 	struct trapframe *tf;
283 	struct proc *p = l->l_proc;
284 
285 #if defined(USER_LDT)
286 	pmap_ldt_cleanup(l);
287 #endif
288 
289 	netbsd32_adjust_limits(p);
290 
291 	fpu_clear(l, __Linux_NPXCW__);
292 
293 	kpreempt_disable();
294 	pcb->pcb_flags = PCB_COMPAT32;
295 	p->p_flag |= PK_32;
296 	l->l_md.md_flags = MDL_COMPAT32;	/* force iret not sysret */
297 	cpu_segregs32_zero(l);
298 	cpu_fsgs_reload(l, GSEL(GUDATA32_SEL, SEL_UPL),
299 	    GSEL(GUDATA32_SEL, SEL_UPL));
300 	kpreempt_enable();
301 
302 	tf = l->l_md.md_regs;
303 	tf->tf_rax = 0;
304 	tf->tf_rbx = (u_int32_t)p->p_psstrp;
305 	tf->tf_rcx = pack->ep_entry & 0xffffffff;
306 	tf->tf_rdx = 0;
307 	tf->tf_rsi = 0;
308 	tf->tf_rdi = 0;
309 	tf->tf_rbp = 0;
310 	tf->tf_rsp = stack & 0xffffffff;
311 	tf->tf_r8 = 0;
312 	tf->tf_r9 = 0;
313 	tf->tf_r10 = 0;
314 	tf->tf_r11 = 0;
315 	tf->tf_r12 = 0;
316 	tf->tf_r13 = 0;
317 	tf->tf_r14 = 0;
318 	tf->tf_r15 = 0;
319 	tf->tf_rip = pack->ep_entry & 0xffffffff;
320 	tf->tf_rflags = PSL_USERSET;
321 	tf->tf_cs = GSEL(GUCODE32_SEL, SEL_UPL);
322 	tf->tf_ss = GSEL(GUDATA32_SEL, SEL_UPL);
323 	tf->tf_ds = GSEL(GUDATA32_SEL, SEL_UPL);
324 	tf->tf_es = GSEL(GUDATA32_SEL, SEL_UPL);
325 }
326 
327 static void
linux32_save_ucontext(struct lwp * l,struct trapframe * tf,const sigset_t * mask,stack_t * sas,struct linux32_ucontext * uc)328 linux32_save_ucontext(struct lwp *l, struct trapframe *tf,
329     const sigset_t *mask, stack_t *sas, struct linux32_ucontext *uc)
330 {
331 
332 	uc->uc_flags = 0;
333 	NETBSD32PTR32(uc->uc_link, NULL);
334 	native_to_linux32_sigaltstack(&uc->uc_stack, sas);
335 	linux32_save_sigcontext(l, tf, mask, &uc->uc_mcontext);
336 	native_to_linux32_sigset(&uc->uc_sigmask, mask);
337 	(void)memset(&uc->uc_fpregs_mem, 0, sizeof(uc->uc_fpregs_mem));
338 }
339 
340 static void
linux32_save_sigcontext(struct lwp * l,struct trapframe * tf,const sigset_t * mask,struct linux32_sigcontext * sc)341 linux32_save_sigcontext(struct lwp *l, struct trapframe *tf,
342 			const sigset_t *mask, struct linux32_sigcontext *sc)
343 {
344 	struct pcb *pcb = lwp_getpcb(l);
345 
346 	/* Save register context. */
347 	sc->sc_gs = tf->tf_gs & 0xFFFF;
348 	sc->sc_fs = tf->tf_fs & 0xFFFF;
349 	sc->sc_es = tf->tf_es & 0xFFFF;
350 	sc->sc_ds = tf->tf_ds & 0xFFFF;
351 	sc->sc_eflags = tf->tf_rflags;
352 	sc->sc_edi = tf->tf_rdi;
353 	sc->sc_esi = tf->tf_rsi;
354 	sc->sc_esp = tf->tf_rsp;
355 	sc->sc_ebp = tf->tf_rbp;
356 	sc->sc_ebx = tf->tf_rbx;
357 	sc->sc_edx = tf->tf_rdx;
358 	sc->sc_ecx = tf->tf_rcx;
359 	sc->sc_eax = tf->tf_rax;
360 	sc->sc_eip = tf->tf_rip;
361 	sc->sc_cs = tf->tf_cs & 0xFFFF;
362 	sc->sc_esp_at_signal = tf->tf_rsp;
363 	sc->sc_ss = tf->tf_ss & 0xFFFF;
364 	sc->sc_err = tf->tf_err;
365 	sc->sc_trapno = tf->tf_trapno;
366 	sc->sc_cr2 = pcb->pcb_cr2;
367 	NETBSD32PTR32(sc->sc_387, NULL);
368 
369 	/* Save signal stack. */
370 	/* Linux doesn't save the onstack flag in sigframe */
371 
372 	/* Save signal mask. */
373 	native_to_linux32_old_sigset(&sc->sc_mask, mask);
374 }
375 
376 int
linux32_sys_sigreturn(struct lwp * l,const struct linux32_sys_sigreturn_args * uap,register_t * retval)377 linux32_sys_sigreturn(struct lwp *l,
378     const struct linux32_sys_sigreturn_args *uap, register_t *retval)
379 {
380 	/* {
381 		syscallarg(linux32_sigcontextp_t) scp;
382 	} */
383 	struct linux32_sigcontext ctx;
384 	int error;
385 
386 	if ((error = copyin(SCARG_P32(uap, scp), &ctx, sizeof(ctx))) != 0)
387 		return error;
388 
389 	return linux32_restore_sigcontext(l, &ctx, retval);
390 }
391 
392 int
linux32_sys_rt_sigreturn(struct lwp * l,const struct linux32_sys_rt_sigreturn_args * uap,register_t * retval)393 linux32_sys_rt_sigreturn(struct lwp *l,
394     const struct linux32_sys_rt_sigreturn_args *uap, register_t *retval)
395 {
396 	/* {
397 		syscallarg(linux32_ucontextp_t) ucp;
398 	} */
399 	struct linux32_ucontext ctx;
400 	int error;
401 
402 	if ((error = copyin(SCARG_P32(uap, ucp), &ctx, sizeof(ctx))) != 0)
403 		return error;
404 
405 	return linux32_restore_sigcontext(l, &ctx.uc_mcontext, retval);
406 }
407 
408 static int
linux32_restore_sigcontext(struct lwp * l,struct linux32_sigcontext * scp,register_t * retval)409 linux32_restore_sigcontext(struct lwp *l, struct linux32_sigcontext *scp,
410 			register_t *retval)
411 {
412 	struct trapframe *tf;
413 	struct proc *p = l->l_proc;
414 	stack_t *sas = &l->l_sigstk;
415 	struct pcb *pcb;
416 	sigset_t mask;
417 	ssize_t ss_gap;
418 	register_t fssel, gssel;
419 
420 	/* Restore register context. */
421 	tf = l->l_md.md_regs;
422 	pcb = lwp_getpcb(l);
423 	DPRINTF(("sigreturn enter rsp=0x%lx rip=0x%lx\n", tf->tf_rsp,
424 		 tf->tf_rip));
425 
426 	/*
427 	 * Check for security violations.
428 	 */
429 	if (((scp->sc_eflags ^ tf->tf_rflags) & PSL_USERSTATIC) != 0)
430 		return EINVAL;
431 	if (!VALID_USER_CSEL32(scp->sc_cs))
432 		return EINVAL;
433 
434 	if (scp->sc_fs != 0 && !VALID_USER_DSEL32(scp->sc_fs) &&
435 	    !(VALID_USER_FSEL32(scp->sc_fs) && pcb->pcb_fs != 0))
436 		return EINVAL;
437 
438 	if (scp->sc_gs != 0 && !VALID_USER_DSEL32(scp->sc_gs) &&
439 	    !(VALID_USER_GSEL32(scp->sc_gs) && pcb->pcb_gs != 0))
440 		return EINVAL;
441 
442 	if (scp->sc_es != 0 && !VALID_USER_DSEL32(scp->sc_es))
443 		return EINVAL;
444 
445 	if (!VALID_USER_DSEL32(scp->sc_ds) ||
446 	    !VALID_USER_DSEL32(scp->sc_ss))
447 		return EINVAL;
448 
449 	if (scp->sc_eip >= VM_MAXUSER_ADDRESS32)
450 		return EINVAL;
451 
452 	gssel = (register_t)scp->sc_gs & 0xffff;
453 	fssel = (register_t)scp->sc_fs & 0xffff;
454 	cpu_fsgs_reload(l, fssel, gssel);
455 	tf->tf_es = (register_t)scp->sc_es & 0xffff;
456 	tf->tf_ds = (register_t)scp->sc_ds & 0xffff;
457 	tf->tf_rflags &= ~PSL_USER;
458 	tf->tf_rflags |= ((register_t)scp->sc_eflags & PSL_USER);
459 	tf->tf_rdi = (register_t)scp->sc_edi & 0xffffffff;
460 	tf->tf_rsi = (register_t)scp->sc_esi & 0xffffffff;
461 	tf->tf_rbp = (register_t)scp->sc_ebp & 0xffffffff;
462 	tf->tf_rbx = (register_t)scp->sc_ebx & 0xffffffff;
463 	tf->tf_rdx = (register_t)scp->sc_edx & 0xffffffff;
464 	tf->tf_rcx = (register_t)scp->sc_ecx & 0xffffffff;
465 	tf->tf_rax = (register_t)scp->sc_eax & 0xffffffff;
466 	tf->tf_rip = (register_t)scp->sc_eip & 0xffffffff;
467 	tf->tf_cs = (register_t)scp->sc_cs & 0xffff;
468 	tf->tf_rsp = (register_t)scp->sc_esp_at_signal & 0xffffffff;
469 	tf->tf_ss = (register_t)scp->sc_ss & 0xffff;
470 
471 	mutex_enter(p->p_lock);
472 
473 	/* Restore signal stack. */
474 	ss_gap = (ssize_t)
475 	    ((char *)NETBSD32IPTR64(scp->sc_esp_at_signal)
476 	     - (char *)sas->ss_sp);
477 	if (ss_gap >= 0 && ss_gap < sas->ss_size)
478 		sas->ss_flags |= SS_ONSTACK;
479 	else
480 		sas->ss_flags &= ~SS_ONSTACK;
481 
482 	/* Restore signal mask. */
483 	linux32_old_to_native_sigset(&mask, &scp->sc_mask);
484 	(void) sigprocmask1(l, SIG_SETMASK, &mask, 0);
485 
486 	mutex_exit(p->p_lock);
487 
488 	DPRINTF(("linux32_sigreturn: rip = 0x%lx, rsp = 0x%lx, flags = 0x%lx\n",
489 	    tf->tf_rip, tf->tf_rsp, tf->tf_rflags));
490 	return EJUSTRETURN;
491 }
492 
493 int
linux32_sys_set_thread_area(struct lwp * l,const struct linux32_sys_set_thread_area_args * uap,register_t * retval)494 linux32_sys_set_thread_area(struct lwp *l,
495     const struct linux32_sys_set_thread_area_args *uap, register_t *retval)
496 {
497 	/* {
498 		syscallarg(linux32_user_descp_t) desc;
499 	} */
500 
501 	return linux_lwp_setprivate(l, SCARG_P32(uap, desc));
502 }
503 
504 int
linux32_sys_get_thread_area(struct lwp * l,const struct linux32_sys_get_thread_area_args * uap,register_t * retval)505 linux32_sys_get_thread_area(struct lwp *l,
506     const struct linux32_sys_get_thread_area_args *uap, register_t *retval)
507 {
508 	/* {
509 		syscallarg(linux32_user_descp_t) desc;
510 	} */
511 
512 	/* glibc doesn't actually call this. */
513 	return ENOSYS;
514 }
515 
516 int
linux32_sys_modify_ldt(struct lwp * l,const struct linux32_sys_modify_ldt_args * uap,register_t * retval)517 linux32_sys_modify_ldt(struct lwp *l, const struct linux32_sys_modify_ldt_args *uap, register_t *retval)
518 {
519 	/* {
520 		syscallarg(int) func;
521 		syscallarg(netbsd32_charp) ptr;
522 		syscallarg(netbsd32_size_t) bytecount;
523 	} */
524 	struct linux_sys_modify_ldt_args ua;
525 
526 	NETBSD32TO64_UAP(func);
527 	NETBSD32TOP_UAP(ptr, void *);
528 	NETBSD32TOX_UAP(bytecount, size_t);
529 	return linux_sys_modify_ldt(l, &ua, retval);
530 }
531