1 /*        $NetBSD: netbsd32_machdep.c,v 1.142 2025/04/24 23:51:03 riastradh Exp $         */
2 
3 /*
4  * Copyright (c) 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Frank van der Linden for Wasabi Systems, Inc.
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  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed for the NetBSD Project by
20  *      Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: netbsd32_machdep.c,v 1.142 2025/04/24 23:51:03 riastradh Exp $");
40 
41 #ifdef _KERNEL_OPT
42 #include "opt_compat_netbsd.h"
43 #include "opt_compat_netbsd32.h"
44 #include "opt_execfmt.h"
45 #include "opt_user_ldt.h"
46 #include "opt_mtrr.h"
47 #endif
48 
49 #include <sys/param.h>
50 #include <sys/exec.h>
51 #include <sys/exec_aout.h>
52 #include <sys/kmem.h>
53 #include <sys/kmem.h>
54 #include <sys/proc.h>
55 #include <sys/signalvar.h>
56 #include <sys/systm.h>
57 #include <sys/core.h>
58 #include <sys/mount.h>
59 #include <sys/buf.h>
60 #include <sys/vnode.h>
61 #include <sys/ras.h>
62 #include <sys/ptrace.h>
63 #include <sys/kauth.h>
64 #include <sys/compat_stub.h>
65 
66 #include <x86/fpu.h>
67 #include <x86/dbregs.h>
68 #include <machine/frame.h>
69 #include <machine/reg.h>
70 #include <machine/vmparam.h>
71 #ifdef MTRR
72 #include <machine/mtrr.h>
73 #endif
74 #include <machine/netbsd32_machdep.h>
75 #include <machine/sysarch.h>
76 #include <machine/userret.h>
77 #include <machine/gdt.h>
78 #include <machine/pmap_private.h>
79 
80 #include <compat/netbsd32/netbsd32.h>
81 #include <compat/netbsd32/netbsd32_exec.h>
82 #include <compat/netbsd32/netbsd32_syscallargs.h>
83 
84 #include <compat/sys/signal.h>
85 #include <compat/sys/signalvar.h>
86 
87 /* Provide a the name of the architecture we're emulating */
88 const char machine32[] = "i386";
89 const char machine_arch32[] = "i386";
90 
91 static int netbsd32_process_doxmmregs(struct lwp *, struct lwp *, void *, bool);
92 static int netbsd32_process_xmmregio(struct lwp *, struct lwp *, struct uio *);
93 
94 #ifdef USER_LDT
95 static int x86_64_get_ldt32(struct lwp *, void *, register_t *);
96 static int x86_64_set_ldt32(struct lwp *, void *, register_t *);
97 #else
98 #define x86_64_get_ldt32(x, y, z)       ENOSYS
99 #define x86_64_set_ldt32(x, y, z)       ENOSYS
100 #endif
101 
102 #ifdef MTRR
103 static int x86_64_get_mtrr32(struct lwp *, void *, register_t *);
104 static int x86_64_set_mtrr32(struct lwp *, void *, register_t *);
105 #else
106 #define x86_64_get_mtrr32(x, y, z)      ENOSYS
107 #define x86_64_set_mtrr32(x, y, z)      ENOSYS
108 #endif
109 
110 int check_sigcontext32(struct lwp *, const struct netbsd32_sigcontext *);
111 void netbsd32_buildcontext(struct lwp *, struct trapframe *, void *,
112     sig_t, int);
113 
114 #ifdef EXEC_AOUT
115 /*
116  * There is no native a.out -- this function is required
117  * for i386 a.out emulation (COMPAT_NETBSD32+EXEC_AOUT).
118  */
119 int
cpu_exec_aout_makecmds(struct lwp * p,struct exec_package * e)120 cpu_exec_aout_makecmds(struct lwp *p, struct exec_package *e)
121 {
122 
123           return ENOEXEC;
124 }
125 #endif
126 
127 void
netbsd32_setregs(struct lwp * l,struct exec_package * pack,vaddr_t stack)128 netbsd32_setregs(struct lwp *l, struct exec_package *pack, vaddr_t stack)
129 {
130           struct pcb *pcb;
131           struct trapframe *tf;
132           struct proc *p = l->l_proc;
133 
134           pcb = lwp_getpcb(l);
135 
136 #if defined(USER_LDT)
137           pmap_ldt_cleanup(l);
138 #endif
139 
140           netbsd32_adjust_limits(p);
141 
142           fpu_clear(l, pack->ep_osversion >= 699002600
143               ?  __NetBSD_NPXCW__ : __NetBSD_COMPAT_NPXCW__);
144           x86_dbregs_clear(l);
145 
146           kpreempt_disable();
147           pcb->pcb_flags = PCB_COMPAT32;
148           p->p_flag |= PK_32;
149           l->l_md.md_flags = MDL_COMPAT32;        /* force iret not sysret */
150           cpu_segregs32_zero(l);
151           cpu_fsgs_reload(l, LSEL(LUDATA32_SEL, SEL_UPL),
152               LSEL(LUDATA32_SEL, SEL_UPL));
153           kpreempt_enable();
154 
155           tf = l->l_md.md_regs;
156           tf->tf_ds = LSEL(LUDATA32_SEL, SEL_UPL);
157           tf->tf_es = LSEL(LUDATA32_SEL, SEL_UPL);
158           tf->tf_rdi = 0;
159           tf->tf_rsi = 0;
160           tf->tf_rbp = 0;
161           tf->tf_rbx = (uint32_t)p->p_psstrp;
162           tf->tf_rdx = 0;
163           tf->tf_rcx = 0;
164           tf->tf_rax = 0;
165           tf->tf_rip = pack->ep_entry;
166           tf->tf_cs = LSEL(LUCODE32_SEL, SEL_UPL);
167           tf->tf_rflags = PSL_USERSET;
168           tf->tf_rsp = stack;
169           tf->tf_ss = LSEL(LUDATA32_SEL, SEL_UPL);
170 }
171 
172 void
netbsd32_buildcontext(struct lwp * l,struct trapframe * tf,void * fp,sig_t catcher,int onstack)173 netbsd32_buildcontext(struct lwp *l, struct trapframe *tf, void *fp,
174     sig_t catcher, int onstack)
175 {
176           /*
177            * Build context to run handler in.
178            */
179           tf->tf_ds = GSEL(GUDATA32_SEL, SEL_UPL);
180           tf->tf_es = GSEL(GUDATA32_SEL, SEL_UPL);
181 #if 0
182           tf->tf_fs = GSEL(GUDATA32_SEL, SEL_UPL);
183           tf->tf_gs = GSEL(GUDATA32_SEL, SEL_UPL);
184 #endif
185 
186           /* Ensure FP state is sane. */
187           fpu_sigreset(l);
188 
189           tf->tf_rip = (uint64_t)catcher;
190           tf->tf_cs = GSEL(GUCODE32_SEL, SEL_UPL);
191           tf->tf_rflags &= ~PSL_CLEARSIG;
192           tf->tf_rsp = (uint64_t)fp;
193           tf->tf_ss = GSEL(GUDATA32_SEL, SEL_UPL);
194 
195           /* Remember that we're now on the signal stack. */
196           if (onstack)
197                     l->l_sigstk.ss_flags |= SS_ONSTACK;
198           if ((vaddr_t)catcher >= VM_MAXUSER_ADDRESS32) {
199                     /*
200                      * process has given an invalid address for the
201                      * handler. Stop it, but do not do it before so
202                      * we can return the right info to userland (or in core dump)
203                      */
204                     sigexit(l, SIGILL);
205                     /* NOTREACHED */
206           }
207 }
208 
209 void
netbsd32_sendsig_siginfo(const ksiginfo_t * ksi,const sigset_t * mask)210 netbsd32_sendsig_siginfo(const ksiginfo_t *ksi, const sigset_t *mask)
211 {
212           struct lwp *l = curlwp;
213           struct proc *p = l->l_proc;
214           struct sigacts *ps = p->p_sigacts;
215           int onstack, error;
216           int sig = ksi->ksi_signo;
217           struct netbsd32_sigframe_siginfo *fp, frame;
218           const struct sigaction *sa = &SIGACTION(p, sig);
219           sig_t catcher = sa->sa_handler;
220           struct trapframe *tf = l->l_md.md_regs;
221           stack_t * const ss = &l->l_sigstk;
222 
223           /* Do we need to jump onto the signal stack? */
224           onstack =
225               (ss->ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
226               (sa->sa_flags & SA_ONSTACK) != 0;
227 
228           /* Allocate space for the signal handler context. */
229           if (onstack)
230                     fp = (struct netbsd32_sigframe_siginfo *)
231                         ((char *)ss->ss_sp + ss->ss_size);
232           else
233                     fp = (struct netbsd32_sigframe_siginfo *)tf->tf_rsp;
234 
235           fp--;
236           fp = (struct netbsd32_sigframe_siginfo *)((uintptr_t)fp &
237               ~STACK_ALIGNBYTES32);
238 
239           /* Build stack frame for signal trampoline. */
240           switch (ps->sa_sigdesc[sig].sd_vers) {
241           case __SIGTRAMP_SIGCODE_VERSION:     /* handled by sendsig_sigcontext */
242           case __SIGTRAMP_SIGCONTEXT_VERSION: /* handled by sendsig_sigcontext */
243           default:  /* unknown version */
244                     printf("nsendsig: bad version %d\n",
245                         ps->sa_sigdesc[sig].sd_vers);
246                     sigexit(l, SIGILL);
247           case __SIGTRAMP_SIGINFO_VERSION:
248                     break;
249           }
250 
251           memset(&frame, 0, sizeof(frame));
252           frame.sf_ra = (uint32_t)(uintptr_t)ps->sa_sigdesc[sig].sd_tramp;
253           frame.sf_signum = sig;
254           frame.sf_sip = (uint32_t)(uintptr_t)&fp->sf_si;
255           frame.sf_ucp = (uint32_t)(uintptr_t)&fp->sf_uc;
256           netbsd32_si_to_si32(&frame.sf_si, (const siginfo_t *)&ksi->ksi_info);
257           frame.sf_uc.uc_flags = _UC_SIGMASK;
258           frame.sf_uc.uc_sigmask = *mask;
259           frame.sf_uc.uc_link = (uint32_t)(uintptr_t)l->l_ctxlink;
260           frame.sf_uc.uc_flags |= (ss->ss_flags & SS_ONSTACK)
261               ? _UC_SETSTACK : _UC_CLRSTACK;
262           sendsig_reset(l, sig);
263 
264           mutex_exit(p->p_lock);
265           cpu_getmcontext32(l, &frame.sf_uc.uc_mcontext, &frame.sf_uc.uc_flags);
266           error = copyout(&frame, fp, sizeof(frame));
267           mutex_enter(p->p_lock);
268 
269           if (error != 0) {
270                     /*
271                      * Process has trashed its stack; give it an illegal
272                      * instruction to halt it in its tracks.
273                      */
274                     sigexit(l, SIGILL);
275                     /* NOTREACHED */
276           }
277 
278           netbsd32_buildcontext(l, tf, fp, catcher, onstack);
279 }
280 
281 /*
282  * Dump the machine specific segment at the start of a core dump.
283  */
284 struct md_core32 {
285           struct reg32 intreg;
286           struct fpreg32 freg;
287 };
288 
289 int
cpu_coredump32(struct lwp * l,struct coredump_iostate * iocookie,struct core32 * chdr)290 cpu_coredump32(struct lwp *l, struct coredump_iostate *iocookie,
291     struct core32 *chdr)
292 {
293           struct md_core32 md_core;
294           struct coreseg cseg;
295           int error;
296 
297           if (iocookie == NULL) {
298                     CORE_SETMAGIC(*chdr, COREMAGIC, MID_I386, 0);
299                     chdr->c_hdrsize = ALIGN32(sizeof(*chdr));
300                     chdr->c_seghdrsize = ALIGN32(sizeof(cseg));
301                     chdr->c_cpusize = sizeof(md_core);
302                     chdr->c_nseg++;
303                     return 0;
304           }
305 
306           /* Save integer registers. */
307           error = netbsd32_process_read_regs(l, &md_core.intreg);
308           if (error)
309                     return error;
310 
311           /* Save floating point registers. */
312           error = netbsd32_process_read_fpregs(l, &md_core.freg, NULL);
313           if (error)
314                     return error;
315 
316           CORE_SETMAGIC(cseg, CORESEGMAGIC, MID_I386, CORE_CPU);
317           cseg.c_addr = 0;
318           cseg.c_size = chdr->c_cpusize;
319 
320           MODULE_HOOK_CALL(coredump_write_hook, (iocookie, UIO_SYSSPACE, &cseg,
321               chdr->c_seghdrsize), ENOSYS, error);
322           if (error)
323                     return error;
324 
325           MODULE_HOOK_CALL(coredump_write_hook, (iocookie, UIO_SYSSPACE, &md_core,
326               sizeof(md_core)), ENOSYS, error);
327 
328           return error;
329 }
330 
331 int
netbsd32_ptrace_translate_request(int req)332 netbsd32_ptrace_translate_request(int req)
333 {
334 
335           switch (req)
336           {
337           case 0 ... PT_FIRSTMACH - 1:  return req;
338           case PT32_STEP:                         return PT_STEP;
339           case PT32_GETREGS:            return PT_GETREGS;
340           case PT32_SETREGS:            return PT_SETREGS;
341           case PT32_GETFPREGS:                    return PT_GETFPREGS;
342           case PT32_SETFPREGS:                    return PT_SETFPREGS;
343           case PT32_GETXMMREGS:                   return PT_GETXMMREGS;
344           case PT32_SETXMMREGS:                   return PT_SETXMMREGS;
345           case PT32_GETDBREGS:                    return PT_GETDBREGS;
346           case PT32_SETDBREGS:                    return PT_SETDBREGS;
347           case PT32_SETSTEP:            return PT_SETSTEP;
348           case PT32_CLEARSTEP:                    return PT_CLEARSTEP;
349           case PT32_GETXSTATE:                    return PT_GETXSTATE;
350           case PT32_SETXSTATE:                    return PT_SETXSTATE;
351           default:                      return -1;
352           }
353 }
354 
355 int
netbsd32_process_read_regs(struct lwp * l,struct reg32 * regs)356 netbsd32_process_read_regs(struct lwp *l, struct reg32 *regs)
357 {
358           struct trapframe *tf = l->l_md.md_regs;
359 
360           /* XXX avoid sign extension problems with unknown upper bits? */
361           regs->r_gs = tf->tf_gs & 0xffff;
362           regs->r_fs = tf->tf_fs & 0xffff;
363           regs->r_es = tf->tf_es & 0xffff;
364           regs->r_ds = tf->tf_ds & 0xffff;
365           regs->r_eflags = tf->tf_rflags;
366           regs->r_edi = tf->tf_rdi & 0xffffffff;
367           regs->r_esi = tf->tf_rsi & 0xffffffff;
368           regs->r_ebp = tf->tf_rbp & 0xffffffff;
369           regs->r_ebx = tf->tf_rbx & 0xffffffff;
370           regs->r_edx = tf->tf_rdx & 0xffffffff;
371           regs->r_ecx = tf->tf_rcx & 0xffffffff;
372           regs->r_eax = tf->tf_rax & 0xffffffff;
373           regs->r_eip = tf->tf_rip & 0xffffffff;
374           regs->r_cs = tf->tf_cs & 0xffff;
375           regs->r_esp = tf->tf_rsp & 0xffffffff;
376           regs->r_ss = tf->tf_ss & 0xffff;
377 
378           return 0;
379 }
380 
381 int
netbsd32_process_read_fpregs(struct lwp * l,struct fpreg32 * regs,size_t * sz)382 netbsd32_process_read_fpregs(struct lwp *l, struct fpreg32 *regs, size_t *sz)
383 {
384 
385           __CTASSERT(sizeof(*regs) == sizeof(struct save87));
386           process_read_fpregs_s87(l, (struct save87 *)regs);
387           return 0;
388 }
389 
390 int
netbsd32_process_read_dbregs(struct lwp * l,struct dbreg32 * regs,size_t * sz)391 netbsd32_process_read_dbregs(struct lwp *l, struct dbreg32 *regs, size_t *sz)
392 {
393           struct dbreg regs64;
394 
395           x86_dbregs_read(l, &regs64);
396           memset(regs, 0, sizeof(*regs));
397           regs->dr[0] = regs64.dr[0] & 0xffffffff;
398           regs->dr[1] = regs64.dr[1] & 0xffffffff;
399           regs->dr[2] = regs64.dr[2] & 0xffffffff;
400           regs->dr[3] = regs64.dr[3] & 0xffffffff;
401 
402           regs->dr[6] = regs64.dr[6] & 0xffffffff;
403           regs->dr[7] = regs64.dr[7] & 0xffffffff;
404 
405           return 0;
406 }
407 
408 int
netbsd32_process_write_regs(struct lwp * l,const struct reg32 * regs)409 netbsd32_process_write_regs(struct lwp *l, const struct reg32 *regs)
410 {
411           struct trapframe *tf;
412           struct pcb *pcb;
413 
414           tf = l->l_md.md_regs;
415           pcb = lwp_getpcb(l);
416 
417           /*
418            * Check for security violations.
419            */
420           if (((regs->r_eflags ^ tf->tf_rflags) & PSL_USERSTATIC) != 0)
421                     return EINVAL;
422           if (!VALID_USER_CSEL32(regs->r_cs))
423                     return EINVAL;
424           if (regs->r_fs != 0 && !VALID_USER_DSEL32(regs->r_fs) &&
425               !(VALID_USER_FSEL32(regs->r_fs) && pcb->pcb_fs != 0))
426                     return EINVAL;
427           if (regs->r_gs != 0 && !VALID_USER_DSEL32(regs->r_gs) &&
428               !(VALID_USER_GSEL32(regs->r_gs) && pcb->pcb_gs != 0))
429                     return EINVAL;
430           if (regs->r_es != 0 && !VALID_USER_DSEL32(regs->r_es))
431                     return EINVAL;
432           if (!VALID_USER_DSEL32(regs->r_ds) ||
433               !VALID_USER_DSEL32(regs->r_ss))
434                     return EINVAL;
435           if ((u_int)regs->r_eip >= VM_MAXUSER_ADDRESS32)
436                     return EINVAL;
437 
438           tf->tf_rax = regs->r_eax;
439           tf->tf_rcx = regs->r_ecx;
440           tf->tf_rdx = regs->r_edx;
441           tf->tf_rbx = regs->r_ebx;
442           tf->tf_rsp = regs->r_esp;
443           tf->tf_rbp = regs->r_ebp;
444           tf->tf_rsi = regs->r_esi;
445           tf->tf_rdi = regs->r_edi;
446           tf->tf_rip = regs->r_eip;
447           tf->tf_rflags = regs->r_eflags;
448           tf->tf_cs = regs->r_cs & 0xFFFF;
449           tf->tf_ss = regs->r_ss & 0xFFFF;
450           tf->tf_ds = regs->r_ds & 0xFFFF;
451           tf->tf_es = regs->r_es & 0xFFFF;
452           tf->tf_fs = regs->r_fs & 0xFFFF;
453           tf->tf_gs = regs->r_gs & 0xFFFF;
454 
455           return 0;
456 }
457 
458 int
netbsd32_process_write_fpregs(struct lwp * l,const struct fpreg32 * regs,size_t sz)459 netbsd32_process_write_fpregs(struct lwp *l, const struct fpreg32 *regs,
460     size_t sz)
461 {
462 
463           __CTASSERT(sizeof(*regs) == sizeof(struct save87));
464           process_write_fpregs_s87(l, (const struct save87 *)regs);
465           return 0;
466 }
467 
468 int
netbsd32_process_write_dbregs(struct lwp * l,const struct dbreg32 * regs,size_t sz)469 netbsd32_process_write_dbregs(struct lwp *l, const struct dbreg32 *regs,
470     size_t sz)
471 {
472           size_t i;
473           struct dbreg regs64;
474 
475           /* Check that DR0-DR3 contain user-space address */
476           for (i = 0; i < X86_DBREGS; i++) {
477                     if ((u_int)regs->dr[i] >= VM_MAXUSER_ADDRESS32)
478                               return EINVAL;
479           }
480 
481           if (regs->dr[7] & X86_DR7_GENERAL_DETECT_ENABLE) {
482                     return EINVAL;
483           }
484 
485           memset(&regs64, 0, sizeof(regs64));
486 
487           regs64.dr[0] = (u_int)regs->dr[0];
488           regs64.dr[1] = (u_int)regs->dr[1];
489           regs64.dr[2] = (u_int)regs->dr[2];
490           regs64.dr[3] = (u_int)regs->dr[3];
491 
492           regs64.dr[6] = (u_int)regs->dr[6];
493           regs64.dr[7] = (u_int)regs->dr[7];
494 
495           x86_dbregs_write(l, &regs64);
496           return 0;
497 }
498 
499 static int
netbsd32_process_doxmmregs(struct lwp * curl,struct lwp * l,void * addr,bool write)500 netbsd32_process_doxmmregs(struct lwp *curl, struct lwp *l, void *addr,
501     bool write)
502           /* curl:             tracer */
503           /* l:                          traced */
504 {
505           struct uio uio;
506           struct iovec iov;
507           struct vmspace *vm;
508           int error;
509 
510           if ((curl->l_proc->p_flag & PK_32) == 0 ||
511               (l->l_proc->p_flag & PK_32) == 0)
512                     return EINVAL;
513 
514           if (!process_machdep_validfpu(l->l_proc))
515                     return EINVAL;
516 
517           error = proc_vmspace_getref(curl->l_proc, &vm);
518           if (error)
519                     return error;
520 
521           iov.iov_base = addr;
522           iov.iov_len = sizeof(struct xmmregs32);
523           uio.uio_iov = &iov;
524           uio.uio_iovcnt = 1;
525           uio.uio_offset = 0;
526           uio.uio_resid = sizeof(struct xmmregs32);
527           uio.uio_rw = write ? UIO_WRITE : UIO_READ;
528           uio.uio_vmspace = vm;
529 
530           error = netbsd32_process_xmmregio(curl, l, &uio);
531           uvmspace_free(vm);
532           return error;
533 }
534 
535 static int
netbsd32_process_xmmregio(struct lwp * curl,struct lwp * l,struct uio * uio)536 netbsd32_process_xmmregio(struct lwp *curl, struct lwp *l, struct uio *uio)
537           /* curl:             tracer */
538           /* l:                          traced */
539 {
540           struct xmmregs32 regs;
541           int error;
542           char *kv;
543           size_t kl;
544 
545           kl = sizeof(regs);
546           kv = (char *)&regs;
547 
548           if (uio->uio_offset < 0 || uio->uio_offset > (off_t)kl)
549                     return EINVAL;
550 
551           kv += uio->uio_offset;
552           kl -= uio->uio_offset;
553 
554           if (kl > uio->uio_resid)
555                     kl = uio->uio_resid;
556 
557           process_read_fpregs_xmm(l, &regs.fxstate);
558           error = uiomove(kv, kl, uio);
559           if (error == 0 && uio->uio_rw == UIO_WRITE) {
560                     if (l->l_proc->p_stat != SSTOP)
561                               error = EBUSY;
562                     else
563                               process_write_fpregs_xmm(l, &regs.fxstate);
564           }
565 
566           uio->uio_offset = 0;
567           return error;
568 }
569 
570 int
netbsd32_sysarch(struct lwp * l,const struct netbsd32_sysarch_args * uap,register_t * retval)571 netbsd32_sysarch(struct lwp *l, const struct netbsd32_sysarch_args *uap, register_t *retval)
572 {
573           /* {
574                     syscallarg(int) op;
575                     syscallarg(netbsd32_voidp) parms;
576           } */
577           int error;
578 
579           switch (SCARG(uap, op)) {
580           case X86_IOPL:
581                     error = x86_iopl(l,
582                         NETBSD32PTR64(SCARG(uap, parms)), retval);
583                     break;
584           case X86_GET_LDT:
585                     error = x86_64_get_ldt32(l,
586                         NETBSD32PTR64(SCARG(uap, parms)), retval);
587                     break;
588           case X86_SET_LDT:
589                     error = x86_64_set_ldt32(l,
590                         NETBSD32PTR64(SCARG(uap, parms)), retval);
591                     break;
592           case X86_GET_MTRR:
593                     error = x86_64_get_mtrr32(l,
594                         NETBSD32PTR64(SCARG(uap, parms)), retval);
595                     break;
596           case X86_SET_MTRR:
597                     error = x86_64_set_mtrr32(l,
598                         NETBSD32PTR64(SCARG(uap, parms)), retval);
599                     break;
600           default:
601                     error = EINVAL;
602                     break;
603           }
604           return error;
605 }
606 
607 #ifdef USER_LDT
608 static int
x86_64_set_ldt32(struct lwp * l,void * args,register_t * retval)609 x86_64_set_ldt32(struct lwp *l, void *args, register_t *retval)
610 {
611           struct x86_set_ldt_args32 ua32;
612           struct x86_set_ldt_args ua;
613           union descriptor *descv;
614           int error;
615 
616           if ((error = copyin(args, &ua32, sizeof(ua32))) != 0)
617                     return error;
618 
619           ua.start = ua32.start;
620           ua.num = ua32.num;
621 
622           if (ua.num < 0 || ua.num > MAX_USERLDT_SLOTS)
623                     return EINVAL;
624 
625           const size_t alloc_size = sizeof(*descv) * ua.num;
626 
627           descv = kmem_alloc(alloc_size, KM_SLEEP);
628           error = copyin((void *)(uintptr_t)ua32.desc, descv,
629               sizeof(*descv) * ua.num);
630           if (error == 0)
631                     error = x86_set_ldt1(l, &ua, descv);
632           *retval = ua.start;
633 
634           kmem_free(descv, alloc_size);
635           return error;
636 }
637 
638 static int
x86_64_get_ldt32(struct lwp * l,void * args,register_t * retval)639 x86_64_get_ldt32(struct lwp *l, void *args, register_t *retval)
640 {
641           struct x86_get_ldt_args32 ua32;
642           struct x86_get_ldt_args ua;
643           union descriptor *cp;
644           int error;
645 
646           if ((error = copyin(args, &ua32, sizeof(ua32))) != 0)
647                     return error;
648 
649           ua.start = ua32.start;
650           ua.num = ua32.num;
651 
652           if (ua.num < 0 || ua.num > MAX_USERLDT_SLOTS)
653                     return EINVAL;
654 
655           const size_t alloc_size = ua.num * sizeof(union descriptor);
656 
657           cp = kmem_alloc(alloc_size, KM_SLEEP);
658           error = x86_get_ldt1(l, &ua, cp);
659           *retval = ua.num;
660           if (error == 0)
661                     error = copyout(cp, (void *)(uintptr_t)ua32.desc,
662                         ua.num * sizeof(*cp));
663 
664           kmem_free(cp, alloc_size);
665           return error;
666 }
667 #endif
668 
669 #ifdef MTRR
670 static int
x86_64_get_mtrr32(struct lwp * l,void * args,register_t * retval)671 x86_64_get_mtrr32(struct lwp *l, void *args, register_t *retval)
672 {
673           struct x86_64_get_mtrr_args32 args32;
674           int error, i;
675           int32_t n;
676           struct mtrr32 *m32p, m32;
677           struct mtrr *m64p, *mp;
678           size_t size;
679 
680           m64p = NULL;
681 
682           if (mtrr_funcs == NULL)
683                     return ENOSYS;
684 
685           error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_MTRR_GET,
686               NULL, NULL, NULL, NULL);
687           if (error)
688                     return error;
689 
690           error = copyin(args, &args32, sizeof(args32));
691           if (error != 0)
692                     return error;
693 
694           if (args32.mtrrp == 0) {
695                     n = (MTRR_I686_NFIXED_SOFT + MTRR_I686_NVAR_MAX);
696                     return copyout(&n, (void *)(uintptr_t)args32.n, sizeof(n));
697           }
698 
699           error = copyin((void *)(uintptr_t)args32.n, &n, sizeof(n));
700           if (error != 0)
701                     return error;
702 
703           if (n <= 0 || n > (MTRR_I686_NFIXED_SOFT + MTRR_I686_NVAR_MAX))
704                     return EINVAL;
705 
706           size = n * sizeof(struct mtrr);
707           m64p = kmem_zalloc(size, KM_SLEEP);
708           error = mtrr_get(m64p, &n, l->l_proc, 0);
709           if (error != 0)
710                     goto fail;
711           m32p = (struct mtrr32 *)(uintptr_t)args32.mtrrp;
712           mp = m64p;
713           for (i = 0; i < n; i++) {
714                     m32.base = mp->base;
715                     m32.len = mp->len;
716                     m32.type = mp->type;
717                     m32.flags = mp->flags;
718                     m32.owner = mp->owner;
719                     error = copyout(&m32, m32p, sizeof(m32));
720                     if (error != 0)
721                               break;
722                     mp++;
723                     m32p++;
724           }
725 fail:
726           if (m64p != NULL)
727                     kmem_free(m64p, size);
728           if (error != 0)
729                     n = 0;
730           copyout(&n, (void *)(uintptr_t)args32.n, sizeof(n));
731           return error;
732 }
733 
734 static int
x86_64_set_mtrr32(struct lwp * l,void * args,register_t * retval)735 x86_64_set_mtrr32(struct lwp *l, void *args, register_t *retval)
736 {
737           struct x86_64_set_mtrr_args32 args32;
738           struct mtrr32 *m32p, m32;
739           struct mtrr *m64p, *mp;
740           int error, i;
741           int32_t n;
742           size_t size;
743 
744           m64p = NULL;
745 
746           if (mtrr_funcs == NULL)
747                     return ENOSYS;
748 
749           error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_MTRR_SET,
750               NULL, NULL, NULL, NULL);
751           if (error)
752                     return error;
753 
754           error = copyin(args, &args32, sizeof(args32));
755           if (error != 0)
756                     return error;
757 
758           error = copyin((void *)(uintptr_t)args32.n, &n, sizeof(n));
759           if (error != 0)
760                     return error;
761 
762           if (n <= 0 || n > (MTRR_I686_NFIXED_SOFT + MTRR_I686_NVAR_MAX)) {
763                     error = EINVAL;
764                     goto fail;
765           }
766 
767           size = n * sizeof(struct mtrr);
768           m64p = kmem_zalloc(size, KM_SLEEP);
769           m32p = (struct mtrr32 *)(uintptr_t)args32.mtrrp;
770           mp = m64p;
771           for (i = 0; i < n; i++) {
772                     error = copyin(m32p, &m32, sizeof(m32));
773                     if (error != 0)
774                               goto fail;
775                     mp->base = m32.base;
776                     mp->len = m32.len;
777                     mp->type = m32.type;
778                     mp->flags = m32.flags;
779                     mp->owner = m32.owner;
780                     m32p++;
781                     mp++;
782           }
783 
784           error = mtrr_set(m64p, &n, l->l_proc, 0);
785 fail:
786           if (m64p != NULL)
787                     kmem_free(m64p, size);
788           if (error != 0)
789                     n = 0;
790           copyout(&n, (void *)(uintptr_t)args32.n, sizeof(n));
791           return error;
792 }
793 #endif
794 
795 int
cpu_setmcontext32(struct lwp * l,const mcontext32_t * mcp,unsigned int flags)796 cpu_setmcontext32(struct lwp *l, const mcontext32_t *mcp, unsigned int flags)
797 {
798           struct trapframe *tf = l->l_md.md_regs;
799           const __greg32_t *gr = mcp->__gregs;
800           struct proc *p = l->l_proc;
801           int error;
802 
803           /* Restore register context, if any. */
804           if ((flags & _UC_CPU) != 0) {
805                     /*
806                      * Check for security violations.
807                      */
808                     error = cpu_mcontext32_validate(l, mcp);
809                     if (error != 0)
810                               return error;
811 
812                     cpu_fsgs_reload(l, gr[_REG32_FS], gr[_REG32_GS]);
813                     tf->tf_es = gr[_REG32_ES] & 0xFFFF;
814                     tf->tf_ds = gr[_REG32_DS] & 0xFFFF;
815                     /* Only change the user-alterable part of eflags */
816                     tf->tf_rflags &= ~PSL_USER;
817                     tf->tf_rflags |= (gr[_REG32_EFL] & PSL_USER);
818                     tf->tf_rdi    = gr[_REG32_EDI];
819                     tf->tf_rsi    = gr[_REG32_ESI];
820                     tf->tf_rbp    = gr[_REG32_EBP];
821                     tf->tf_rbx    = gr[_REG32_EBX];
822                     tf->tf_rdx    = gr[_REG32_EDX];
823                     tf->tf_rcx    = gr[_REG32_ECX];
824                     tf->tf_rax    = gr[_REG32_EAX];
825                     tf->tf_rip    = gr[_REG32_EIP];
826                     tf->tf_cs     = gr[_REG32_CS] & 0xFFFF;
827                     tf->tf_rsp    = gr[_REG32_UESP];
828                     tf->tf_ss     = gr[_REG32_SS] & 0xFFFF;
829           }
830 
831           if ((flags & _UC_TLSBASE) != 0)
832                     lwp_setprivate(l, (void *)(uintptr_t)mcp->_mc_tlsbase);
833 
834           /* Restore floating point register context, if any. */
835           if ((flags & _UC_FPU) != 0) {
836                     /* Assume fxsave context */
837                     process_write_fpregs_xmm(l, (const struct fxsave *)
838                         &mcp->__fpregs.__fp_reg_set.__fp_xmm_state);
839           }
840 
841           mutex_enter(p->p_lock);
842           if (flags & _UC_SETSTACK)
843                     l->l_sigstk.ss_flags |= SS_ONSTACK;
844           if (flags & _UC_CLRSTACK)
845                     l->l_sigstk.ss_flags &= ~SS_ONSTACK;
846           mutex_exit(p->p_lock);
847 
848           return 0;
849 }
850 
851 void
cpu_getmcontext32(struct lwp * l,mcontext32_t * mcp,unsigned int * flags)852 cpu_getmcontext32(struct lwp *l, mcontext32_t *mcp, unsigned int *flags)
853 {
854           const struct trapframe *tf = l->l_md.md_regs;
855           __greg32_t *gr = mcp->__gregs;
856           __greg32_t ras_eip;
857 
858           /* Save register context. */
859           gr[_REG32_GS]  = tf->tf_gs & 0xFFFF;
860           gr[_REG32_FS]  = tf->tf_fs & 0xFFFF;
861           gr[_REG32_ES]  = tf->tf_es & 0xFFFF;
862           gr[_REG32_DS]  = tf->tf_ds & 0xFFFF;
863           gr[_REG32_EFL] = tf->tf_rflags;
864           gr[_REG32_EDI]    = tf->tf_rdi;
865           gr[_REG32_ESI]    = tf->tf_rsi;
866           gr[_REG32_EBP]    = tf->tf_rbp;
867           gr[_REG32_EBX]    = tf->tf_rbx;
868           gr[_REG32_EDX]    = tf->tf_rdx;
869           gr[_REG32_ECX]    = tf->tf_rcx;
870           gr[_REG32_EAX]    = tf->tf_rax;
871           gr[_REG32_EIP]    = tf->tf_rip;
872           gr[_REG32_CS]     = tf->tf_cs & 0xFFFF;
873           gr[_REG32_ESP]    = tf->tf_rsp;
874           gr[_REG32_UESP]   = tf->tf_rsp;
875           gr[_REG32_SS]     = tf->tf_ss & 0xFFFF;
876           gr[_REG32_TRAPNO] = tf->tf_trapno;
877           gr[_REG32_ERR]    = tf->tf_err;
878 
879           if ((ras_eip = (__greg32_t)(uintptr_t)ras_lookup(l->l_proc,
880               (void *) (uintptr_t)gr[_REG32_EIP])) != (__greg32_t)-1)
881                     gr[_REG32_EIP] = ras_eip;
882 
883           *flags |= _UC_CPU;
884 
885           mcp->_mc_tlsbase = (uint32_t)(uintptr_t)l->l_private;
886           *flags |= _UC_TLSBASE;
887 
888           /* Save floating point register context. */
889           process_read_fpregs_xmm(l, (struct fxsave *)
890               &mcp->__fpregs.__fp_reg_set.__fp_xmm_state);
891           memset(&mcp->__fpregs.__fp_pad, 0, sizeof(mcp->__fpregs.__fp_pad));
892           *flags |= _UC_FXSAVE | _UC_FPU;
893 }
894 
895 void
startlwp32(void * arg)896 startlwp32(void *arg)
897 {
898           ucontext32_t *uc = arg;
899           lwp_t *l = curlwp;
900           int error __diagused;
901 
902           error = cpu_setmcontext32(l, &uc->uc_mcontext, uc->uc_flags);
903           KASSERT(error == 0);
904 
905           /* Note: we are freeing ucontext_t, not ucontext32_t. */
906           kmem_free(uc, sizeof(ucontext_t));
907           userret(l);
908 }
909 
910 int
check_sigcontext32(struct lwp * l,const struct netbsd32_sigcontext * scp)911 check_sigcontext32(struct lwp *l, const struct netbsd32_sigcontext *scp)
912 {
913           struct pmap *pmap = l->l_proc->p_vmspace->vm_map.pmap;
914           struct trapframe *tf;
915           struct pcb *pcb;
916 
917           tf = l->l_md.md_regs;
918           pcb = lwp_getpcb(curlwp);
919 
920           if (((scp->sc_eflags ^ tf->tf_rflags) & PSL_USERSTATIC) != 0)
921                     return EINVAL;
922 
923           if (__predict_false(pmap->pm_ldt != NULL)) {
924                     /* Allow unfamiliar segment register values (USER_LDT). */
925                     if (!USERMODE(scp->sc_cs))
926                               return EINVAL;
927           } else {
928                     if (!VALID_USER_CSEL32(scp->sc_cs))
929                               return EINVAL;
930                     if (scp->sc_fs != 0 && !VALID_USER_DSEL32(scp->sc_fs) &&
931                         !(VALID_USER_FSEL32(scp->sc_fs) && pcb->pcb_fs != 0))
932                               return EINVAL;
933                     if (scp->sc_gs != 0 && !VALID_USER_DSEL32(scp->sc_gs) &&
934                         !(VALID_USER_GSEL32(scp->sc_gs) && pcb->pcb_gs != 0))
935                               return EINVAL;
936                     if (scp->sc_es != 0 && !VALID_USER_DSEL32(scp->sc_es))
937                               return EINVAL;
938                     if (!VALID_USER_DSEL32(scp->sc_ds) ||
939                         !VALID_USER_DSEL32(scp->sc_ss))
940                               return EINVAL;
941           }
942 
943           if (scp->sc_eip >= VM_MAXUSER_ADDRESS32)
944                     return EINVAL;
945 
946           return 0;
947 }
948 
949 int
cpu_mcontext32_validate(struct lwp * l,const mcontext32_t * mcp)950 cpu_mcontext32_validate(struct lwp *l, const mcontext32_t *mcp)
951 {
952           struct pmap *pmap = l->l_proc->p_vmspace->vm_map.pmap;
953           const __greg32_t *gr;
954           struct trapframe *tf;
955           struct pcb *pcb;
956 
957           gr = mcp->__gregs;
958           tf = l->l_md.md_regs;
959           pcb = lwp_getpcb(l);
960 
961           if (((gr[_REG32_EFL] ^ tf->tf_rflags) & PSL_USERSTATIC) != 0)
962                     return EINVAL;
963 
964           if (__predict_false(pmap->pm_ldt != NULL)) {
965                     /* Allow unfamiliar segment register values (USER_LDT). */
966                     if (!USERMODE(gr[_REG32_CS]))
967                               return EINVAL;
968           } else {
969                     if (!VALID_USER_CSEL32(gr[_REG32_CS]))
970                               return EINVAL;
971                     if (gr[_REG32_FS] != 0 && !VALID_USER_DSEL32(gr[_REG32_FS]) &&
972                         !(VALID_USER_FSEL32(gr[_REG32_FS]) && pcb->pcb_fs != 0))
973                               return EINVAL;
974                     if (gr[_REG32_GS] != 0 && !VALID_USER_DSEL32(gr[_REG32_GS]) &&
975                         !(VALID_USER_GSEL32(gr[_REG32_GS]) && pcb->pcb_gs != 0))
976                               return EINVAL;
977                     if (gr[_REG32_ES] != 0 && !VALID_USER_DSEL32(gr[_REG32_ES]))
978                               return EINVAL;
979                     if (!VALID_USER_DSEL32(gr[_REG32_DS]) ||
980                         !VALID_USER_DSEL32(gr[_REG32_SS]))
981                               return EINVAL;
982           }
983 
984           if (gr[_REG32_EIP] >= VM_MAXUSER_ADDRESS32)
985                     return EINVAL;
986 
987           return 0;
988 }
989 
990 static int
cpu_mcontext32from64_validate(struct lwp * l,const struct reg * regp)991 cpu_mcontext32from64_validate(struct lwp *l, const struct reg *regp)
992 {
993           mcontext32_t mc;
994           __greg32_t *gr32 = mc.__gregs;
995           const __greg_t *gr = regp->regs;
996 
997           memset(&mc, 0, sizeof(mc));
998           gr32[_REG32_EFL] = gr[_REG_RFLAGS];
999           gr32[_REG32_EIP] = gr[_REG_RIP];
1000           gr32[_REG32_CS] = gr[_REG_CS];
1001           gr32[_REG32_DS] = gr[_REG_DS];
1002           gr32[_REG32_ES] = gr[_REG_ES];
1003           gr32[_REG32_FS] = gr[_REG_FS];
1004           gr32[_REG32_GS] = gr[_REG_GS];
1005           gr32[_REG32_SS] = gr[_REG_SS];
1006           return cpu_mcontext32_validate(l, &mc);
1007 }
1008 
1009 vaddr_t
netbsd32_vm_default_addr(struct proc * p,vaddr_t base,vsize_t sz,int topdown)1010 netbsd32_vm_default_addr(struct proc *p, vaddr_t base, vsize_t sz,
1011     int topdown)
1012 {
1013           if (topdown)
1014                     return VM_DEFAULT_ADDRESS32_TOPDOWN(base, sz);
1015           else
1016                     return VM_DEFAULT_ADDRESS32_BOTTOMUP(base, sz);
1017 }
1018 
1019 static const char *
netbsd32_machine32(void)1020 netbsd32_machine32(void)
1021 {
1022 
1023           return machine32;
1024 }
1025 
1026 void
netbsd32_machdep_md_init(void)1027 netbsd32_machdep_md_init(void)
1028 {
1029 
1030           MODULE_HOOK_SET(netbsd32_machine32_hook, netbsd32_machine32);
1031           MODULE_HOOK_SET(netbsd32_reg_validate_hook,
1032               cpu_mcontext32from64_validate);
1033           MODULE_HOOK_SET(netbsd32_process_doxmmregs_hook,
1034               netbsd32_process_doxmmregs);
1035 }
1036 
1037 void
netbsd32_machdep_md_fini(void)1038 netbsd32_machdep_md_fini(void)
1039 {
1040 
1041           MODULE_HOOK_UNSET(netbsd32_machine32_hook);
1042           MODULE_HOOK_UNSET(netbsd32_reg_validate_hook);
1043           MODULE_HOOK_UNSET(netbsd32_process_doxmmregs_hook);
1044 }
1045