1 /* $NetBSD: compat_16_machdep.c,v 1.18 2021/10/27 04:15:00 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9 * NASA Ames Research Center.
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 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: compat_16_machdep.c,v 1.18 2021/10/27 04:15:00 thorpej Exp $");
35
36 #ifdef _KERNEL_OPT
37 #include "opt_compat_netbsd.h"
38 #endif
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/signal.h>
43 #include <sys/signalvar.h>
44 #include <sys/kernel.h>
45 #include <sys/proc.h>
46 #include <sys/mount.h>
47 #include <sys/syscallargs.h>
48
49 #include <machine/signal.h>
50 #include <machine/frame.h>
51
52 #if defined(COMPAT_16)
53 #include <compat/sys/signal.h>
54 #include <compat/sys/signalvar.h>
55
56 #ifdef DEBUG
57 /* See sigdebug.h */
58 #include <sparc64/sparc64/sigdebug.h>
59 #endif
60
61 #ifdef __arch64__
62 #define STACK_OFFSET BIAS
63 #define CPOUTREG(l,v) copyout(&(v), (l), sizeof(v))
64 #undef CCFSZ
65 #define CCFSZ CC64FSZ
66 #else
67 #define STACK_OFFSET 0
68 #define CPOUTREG(l,v) copyout(&(v), (l), sizeof(v))
69 #endif
70
71 struct sigframe_sigcontext {
72 int sf_signo; /* signal number */
73 int sf_code; /* code */
74 #ifndef __arch64__
75 struct sigcontext *sf_scp; /* SunOS user addr of sigcontext */
76 int sf_addr; /* SunOS compat, always 0 for now */
77 #endif
78 struct sigcontext sf_sc; /* actual sigcontext */
79 };
80
81 /*
82 * Send an interrupt to process.
83 */
84 void
sendsig_sigcontext(const ksiginfo_t * ksi,const sigset_t * mask)85 sendsig_sigcontext(const ksiginfo_t *ksi, const sigset_t *mask)
86 {
87 struct lwp *l = curlwp;
88 struct proc *p = l->l_proc;
89 struct sigacts *ps = p->p_sigacts;
90 const void *addr;
91 struct rwindow *newsp;
92 #ifdef NOT_DEBUG
93 struct rwindow tmpwin;
94 #endif
95 int onstack, error;
96 int sig = ksi->ksi_signo;
97 struct sigframe_sigcontext *fp = getframe(l, sig, &onstack);
98 struct sigframe_sigcontext sf;
99 sig_t catcher = SIGACTION(p, sig).sa_handler;
100 struct trapframe64 *tf = l->l_md.md_tf;
101 /* Allocate an aligned sigframe */
102 fp = (void *)((u_long)(fp - 1) & ~0x0f);
103
104 #ifdef DEBUG
105 sigpid = p->p_pid;
106 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid) {
107 printf("sendsig_sigcontext: %s[%d] sig %d newusp %p scp %p\n",
108 p->p_comm, p->p_pid, sig, fp, &fp->sf_sc);
109 #ifdef DDB
110 if (sigdebug & SDB_DDB) Debugger();
111 #endif
112 }
113 #endif
114
115 /*
116 * Now set up the signal frame. We build it in kernel space
117 * and then copy it out. We probably ought to just build it
118 * directly in user space....
119 */
120 sf.sf_signo = sig;
121 sf.sf_code = ksi->ksi_trap;
122 #ifndef __arch64__
123 sf.sf_scp = 0;
124 sf.sf_addr = 0; /* XXX */
125 #endif
126
127 /*
128 * Build the signal context to be used by sigreturn.
129 */
130 sf.sf_sc.sc_onstack = l->l_sigstk.ss_flags & SS_ONSTACK;
131 sf.sf_sc.sc_mask = *mask;
132 #ifdef COMPAT_13
133 /*
134 * XXX We always have to save an old style signal mask because
135 * XXX we might be delivering a signal to a process which will
136 * XXX escape from the signal in a non-standard way and invoke
137 * XXX sigreturn() directly.
138 */
139 native_sigset_to_sigset13(mask, &sf.sf_sc.__sc_mask13);
140 #endif
141 /* Save register context. */
142 sf.sf_sc.sc_sp = (long)tf->tf_out[6];
143 sf.sf_sc.sc_pc = tf->tf_pc;
144 sf.sf_sc.sc_npc = tf->tf_npc;
145 #ifdef __arch64__
146 sf.sf_sc.sc_tstate = tf->tf_tstate; /* XXX */
147 #else
148 sf.sf_sc.sc_psr = TSTATECCR_TO_PSR(tf->tf_tstate); /* XXX */
149 #endif
150 sf.sf_sc.sc_g1 = tf->tf_global[1];
151 sf.sf_sc.sc_o0 = tf->tf_out[0];
152
153 /*
154 * Put the stack in a consistent state before we whack away
155 * at it. Note that write_user_windows may just dump the
156 * registers into the pcb; we need them in the process's memory.
157 * We also need to make sure that when we start the signal handler,
158 * its %i6 (%fp), which is loaded from the newly allocated stack area,
159 * joins seamlessly with the frame it was in when the signal occurred,
160 * so that the debugger and _longjmp code can back up through it.
161 */
162 sendsig_reset(l, sig);
163 mutex_exit(p->p_lock);
164 newsp = (struct rwindow *)((vaddr_t)fp - sizeof(struct rwindow));
165 write_user_windows();
166 #ifdef DEBUG
167 if ((sigdebug & SDB_KSTACK))
168 printf("sendsig: saving sf to %p, setting stack pointer %p to %p\n",
169 fp, &(((struct rwindow *)newsp)->rw_in[6]),
170 (void *)(unsigned long)tf->tf_out[6]);
171 #endif
172 error = (rwindow_save(l) || copyout((void *)&sf, (void *)fp, sizeof sf) ||
173 #ifdef NOT_DEBUG
174 copyin(oldsp, &tmpwin, sizeof(tmpwin)) || copyout(&tmpwin, newsp, sizeof(tmpwin)) ||
175 #endif
176 CPOUTREG(&(((struct rwindow *)newsp)->rw_in[6]), tf->tf_out[6]));
177 mutex_enter(p->p_lock);
178
179 if (error) {
180 /*
181 * Process has trashed its stack; give it an illegal
182 * instruction to halt it in its tracks.
183 */
184 #ifdef DEBUG
185 mutex_exit(p->p_lock);
186 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
187 printf("sendsig: window save or copyout error\n");
188 printf("sendsig: stack was trashed trying to send sig %d, sending SIGILL\n", sig);
189 #ifdef DDB
190 if (sigdebug & SDB_DDB) Debugger();
191 #endif
192 mutex_enter(p->p_lock);
193 #endif
194 sigexit(l, SIGILL);
195 /* NOTREACHED */
196 }
197
198 #ifdef DEBUG
199 if (sigdebug & SDB_FOLLOW) {
200 printf("sendsig: %s[%d] sig %d scp %p\n",
201 p->p_comm, p->p_pid, sig, &fp->sf_sc);
202 }
203 #endif
204
205 /*
206 * Arrange to continue execution at the code copied out in exec().
207 * It needs the function to call in %g1, and a new stack pointer.
208 */
209 switch (ps->sa_sigdesc[sig].sd_vers) {
210 case __SIGTRAMP_SIGCODE_VERSION: /* legacy on-stack sigtramp */
211 addr = p->p_sigctx.ps_sigcode;
212 break;
213
214 case __SIGTRAMP_SIGCONTEXT_VERSION:
215 addr = ps->sa_sigdesc[sig].sd_tramp;
216 break;
217
218 default:
219 addr = NULL; /* XXX: gcc */
220 /* Don't know what trampoline version; kill it. */
221 sigexit(l, SIGILL);
222 }
223
224 tf->tf_global[1] = (vaddr_t)catcher;
225 tf->tf_pc = (const vaddr_t)addr;
226 tf->tf_npc = (const vaddr_t)addr + 4;
227 tf->tf_out[6] = (vaddr_t)newsp - STACK_OFFSET;
228
229 /* Remember that we're now on the signal stack. */
230 if (onstack)
231 l->l_sigstk.ss_flags |= SS_ONSTACK;
232
233 #ifdef DEBUG
234 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid) {
235 mutex_exit(p->p_lock);
236 printf("sendsig: about to return to catcher %p thru %p\n",
237 catcher, (void *)(unsigned long)addr);
238 #ifdef DDB
239 if (sigdebug & SDB_DDB) Debugger();
240 #endif
241 mutex_enter(p->p_lock);
242 }
243 #endif
244 }
245
246 /*
247 * System call to cleanup state after a signal
248 * has been taken. Reset signal mask and
249 * stack state from context left by sendsig (above),
250 * and return to the given trap frame (if there is one).
251 * Check carefully to make sure that the user has not
252 * modified the state to gain improper privileges or to cause
253 * a machine fault.
254 */
255 int compat_16_sys___sigreturn14(struct lwp *, const struct compat_16_sys___sigreturn14_args *, register_t *);
256
257 /* ARGSUSED */
258 int
compat_16_sys___sigreturn14(struct lwp * l,const struct compat_16_sys___sigreturn14_args * uap,register_t * retval)259 compat_16_sys___sigreturn14(struct lwp *l, const struct compat_16_sys___sigreturn14_args *uap, register_t *retval)
260 {
261 /* {
262 syscallarg(struct sigcontext *) sigcntxp;
263 } */
264 struct sigcontext sc, *scp;
265 struct trapframe64 *tf;
266 int error = EINVAL;
267 struct proc *p = l->l_proc;
268
269 /* First ensure consistent stack state (see sendsig). */
270 write_user_windows();
271 if (rwindow_save(l)) {
272 #ifdef DEBUG
273 printf("sigreturn14: rwindow_save(%p) failed, sending SIGILL\n", p);
274 #ifdef DDB
275 if (sigdebug & SDB_DDB) Debugger();
276 #endif
277 #endif
278 mutex_enter(p->p_lock);
279 sigexit(l, SIGILL);
280 }
281 #ifdef DEBUG
282 if (sigdebug & SDB_FOLLOW) {
283 printf("sigreturn14: %s[%d], sigcntxp %p\n",
284 p->p_comm, p->p_pid, SCARG(uap, sigcntxp));
285 #ifdef DDB
286 if (sigdebug & SDB_DDB) Debugger();
287 #endif
288 }
289 #endif
290 scp = SCARG(uap, sigcntxp);
291 if (((vaddr_t)scp & 3) != 0 ||
292 (error = copyin((void *)scp, &sc, sizeof sc)) != 0)
293 #ifdef DEBUG
294 {
295 printf("sigreturn14: copyin failed: scp=%p\n", scp);
296 #ifdef DDB
297 if (sigdebug & SDB_DDB) Debugger();
298 #endif
299 return (error);
300 }
301 #else
302 return (error);
303 #endif
304 scp = ≻
305
306 tf = l->l_md.md_tf;
307 /*
308 * Only the icc bits in the psr are used, so it need not be
309 * verified. pc and npc must be multiples of 4. This is all
310 * that is required; if it holds, just do it.
311 */
312 if (((sc.sc_pc | sc.sc_npc) & 3) != 0 || (sc.sc_pc == 0) || (sc.sc_npc == 0))
313 #ifdef DEBUG
314 {
315 printf("sigreturn14: pc %p or npc %p invalid\n",
316 (void *)(unsigned long)sc.sc_pc,
317 (void *)(unsigned long)sc.sc_npc);
318 #ifdef DDB
319 if (sigdebug & SDB_DDB) Debugger();
320 #endif
321 return (EINVAL);
322 }
323 #else
324 return (EINVAL);
325 #endif
326 /* take only psr ICC field */
327 #ifdef __arch64__
328 tf->tf_tstate = (uint64_t)(tf->tf_tstate & ~TSTATE_CCR) | (scp->sc_tstate & TSTATE_CCR);
329 #else
330 tf->tf_tstate = (uint64_t)(tf->tf_tstate & ~TSTATE_CCR) | PSRCC_TO_TSTATE(scp->sc_psr);
331 #endif
332 tf->tf_pc = (uint64_t)scp->sc_pc;
333 tf->tf_npc = (uint64_t)scp->sc_npc;
334 tf->tf_global[1] = (uint64_t)scp->sc_g1;
335 tf->tf_out[0] = (uint64_t)scp->sc_o0;
336 tf->tf_out[6] = (uint64_t)scp->sc_sp;
337 #ifdef DEBUG
338 if (sigdebug & SDB_FOLLOW) {
339 printf("sigreturn14: return trapframe pc=%p sp=%p tstate=%llx\n",
340 (void *)(unsigned long)tf->tf_pc,
341 (void *)(unsigned long)tf->tf_out[6],
342 (unsigned long long)tf->tf_tstate);
343 #ifdef DDB
344 if (sigdebug & SDB_DDB) Debugger();
345 #endif
346 }
347 #endif
348
349 mutex_enter(p->p_lock);
350 /* Restore signal stack. */
351 if (sc.sc_onstack & SS_ONSTACK)
352 l->l_sigstk.ss_flags |= SS_ONSTACK;
353 else
354 l->l_sigstk.ss_flags &= ~SS_ONSTACK;
355 /* Restore signal mask. */
356 (void) sigprocmask1(l, SIG_SETMASK, &sc.sc_mask, 0);
357 mutex_exit(p->p_lock);
358
359 return (EJUSTRETURN);
360 }
361 #endif /* COMPAT_16 */
362