1 /* $NetBSD: compat_16_machdep.c,v 1.6 2021/10/27 04:15:00 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 1996, 1997, 1998, 2008 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 /*
34 * Copyright (c) 1992, 1993
35 * The Regents of the University of California. All rights reserved.
36 *
37 * This software was developed by the Computer Systems Engineering group
38 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
39 * contributed to Berkeley.
40 *
41 * All advertising materials mentioning features or use of this software
42 * must display the following acknowledgement:
43 * This product includes software developed by the University of
44 * California, Lawrence Berkeley Laboratory.
45 *
46 * Redistribution and use in source and binary forms, with or without
47 * modification, are permitted provided that the following conditions
48 * are met:
49 * 1. Redistributions of source code must retain the above copyright
50 * notice, this list of conditions and the following disclaimer.
51 * 2. Redistributions in binary form must reproduce the above copyright
52 * notice, this list of conditions and the following disclaimer in the
53 * documentation and/or other materials provided with the distribution.
54 * 3. Neither the name of the University nor the names of its contributors
55 * may be used to endorse or promote products derived from this software
56 * without specific prior written permission.
57 *
58 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68 * SUCH DAMAGE.
69 *
70 * @(#)machdep.c 8.6 (Berkeley) 1/14/94
71 */
72
73 #include <sys/cdefs.h>
74 __KERNEL_RCSID(0, "$NetBSD: compat_16_machdep.c,v 1.6 2021/10/27 04:15:00 thorpej Exp $");
75
76 #include <sys/param.h>
77 #include <sys/signal.h>
78 #include <sys/signalvar.h>
79 #include <sys/proc.h>
80 #include <sys/systm.h>
81 #include <sys/kernel.h>
82 #include <sys/syscallargs.h>
83
84 #ifdef COMPAT_13
85 #include <compat/sys/signal.h>
86 #include <compat/sys/signalvar.h>
87 #endif
88 #include <machine/frame.h>
89
90 #ifdef COMPAT_13
91 #include <compat/sys/signal.h>
92 #include <compat/sys/signalvar.h>
93 #endif /* COMPAT_13 */
94
95 struct sigframe_sigcontext {
96 int sf_signo; /* signal number */
97 int sf_code; /* code */
98 struct sigcontext *sf_scp; /* SunOS user addr of sigcontext */
99 int sf_addr; /* SunOS compat, always 0 for now */
100 struct sigcontext sf_sc; /* actual sigcontext */
101 };
102
103 #ifdef DEBUG
104 extern int sigdebug;
105 extern int sigpid;
106 #define SDB_FOLLOW 0x01
107 #define SDB_KSTACK 0x02
108 #define SDB_FPSTATE 0x04
109 #endif
110
111 void
sendsig_sigcontext(const ksiginfo_t * ksi,const sigset_t * mask)112 sendsig_sigcontext(const ksiginfo_t *ksi, const sigset_t *mask)
113 {
114 struct lwp *l = curlwp;
115 struct proc *p = l->l_proc;
116 struct sigacts *ps = p->p_sigacts;
117 struct sigframe_sigcontext *fp;
118 struct trapframe *tf;
119 int addr, onstack, oldsp, newsp, error;
120 struct sigframe_sigcontext sf;
121 int sig = ksi->ksi_signo;
122 u_long code = KSI_TRAPCODE(ksi);
123 sig_t catcher = SIGACTION(p, sig).sa_handler;
124
125 tf = l->l_md.md_tf;
126 oldsp = tf->tf_out[6];
127
128 /*
129 * Compute new user stack addresses, subtract off
130 * one signal frame, and align.
131 */
132 onstack =
133 (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
134 (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
135
136 if (onstack)
137 fp = (struct sigframe_sigcontext *)
138 ((char *)l->l_sigstk.ss_sp +
139 l->l_sigstk.ss_size);
140 else
141 fp = (struct sigframe_sigcontext *)oldsp;
142
143 fp = (struct sigframe_sigcontext *)((int)(fp - 1) & ~7);
144
145 #ifdef DEBUG
146 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
147 printf("sendsig_sigcontext: %s[%d] sig %d newusp %p scp %p\n",
148 p->p_comm, p->p_pid, sig, fp, &fp->sf_sc);
149 #endif
150 /*
151 * Now set up the signal frame. We build it in kernel space
152 * and then copy it out. We probably ought to just build it
153 * directly in user space....
154 */
155 sf.sf_signo = sig;
156 sf.sf_code = code;
157 sf.sf_scp = 0;
158 sf.sf_addr = 0; /* XXX */
159
160 /*
161 * Build the signal context to be used by sigreturn.
162 */
163 sf.sf_sc.sc_onstack = l->l_sigstk.ss_flags & SS_ONSTACK;
164 sf.sf_sc.sc_mask = *mask;
165 #ifdef COMPAT_13
166 /*
167 * XXX We always have to save an old style signal mask because
168 * XXX we might be delivering a signal to a process which will
169 * XXX escape from the signal in a non-standard way and invoke
170 * XXX sigreturn() directly.
171 */
172 native_sigset_to_sigset13(mask, &sf.sf_sc.__sc_mask13);
173 #endif
174 sf.sf_sc.sc_sp = oldsp;
175 sf.sf_sc.sc_pc = tf->tf_pc;
176 sf.sf_sc.sc_npc = tf->tf_npc;
177 sf.sf_sc.sc_psr = tf->tf_psr;
178 sf.sf_sc.sc_g1 = tf->tf_global[1];
179 sf.sf_sc.sc_o0 = tf->tf_out[0];
180
181 /*
182 * Put the stack in a consistent state before we whack away
183 * at it. Note that write_user_windows may just dump the
184 * registers into the pcb; we need them in the process's memory.
185 * We also need to make sure that when we start the signal handler,
186 * its %i6 (%fp), which is loaded from the newly allocated stack area,
187 * joins seamlessly with the frame it was in when the signal occurred,
188 * so that the debugger and _longjmp code can back up through it.
189 */
190 sendsig_reset(l, sig);
191 mutex_exit(p->p_lock);
192 newsp = (int)fp - sizeof(struct rwindow);
193 write_user_windows();
194 error = (rwindow_save(l) || copyout((void *)&sf, (void *)fp, sizeof sf) ||
195 ustore_int((u_int *)&((struct rwindow *)newsp)->rw_in[6], oldsp));
196 mutex_enter(p->p_lock);
197
198 if (error) {
199 /*
200 * Process has trashed its stack; give it an illegal
201 * instruction to halt it in its tracks.
202 */
203 #ifdef DEBUG
204 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
205 printf("sendsig_sigcontext: window save or copyout error\n");
206 #endif
207 sigexit(l, SIGILL);
208 /* NOTREACHED */
209 }
210 #ifdef DEBUG
211 if (sigdebug & SDB_FOLLOW)
212 printf("sendsig_siginfo: %s[%d] sig %d scp %p\n",
213 p->p_comm, p->p_pid, sig, &fp->sf_sc);
214 #endif
215 /*
216 * Arrange to continue execution at the code copied out in exec().
217 * It needs the function to call in %g1, and a new stack pointer.
218 */
219 switch (ps->sa_sigdesc[sig].sd_vers) {
220 case __SIGTRAMP_SIGCODE_VERSION: /* legacy on-stack sigtramp */
221 addr = (int)p->p_sigctx.ps_sigcode;
222 break;
223
224 case __SIGTRAMP_SIGCONTEXT_VERSION:
225 addr = (int)ps->sa_sigdesc[sig].sd_tramp;
226 break;
227
228 default:
229 /* Don't know what trampoline version; kill it. */
230 addr = 0;
231 sigexit(l, SIGILL);
232 }
233
234 tf->tf_global[1] = (int)catcher;
235 tf->tf_pc = addr;
236 tf->tf_npc = addr + 4;
237 tf->tf_out[6] = newsp;
238
239 /* Remember that we're now on the signal stack. */
240 if (onstack)
241 l->l_sigstk.ss_flags |= SS_ONSTACK;
242
243 #ifdef DEBUG
244 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
245 printf("sendsig: about to return to catcher\n");
246 #endif
247 }
248
249 /*
250 * System call to cleanup state after a signal
251 * has been taken. Reset signal mask and
252 * stack state from context left by sendsig (above),
253 * and return to the given trap frame (if there is one).
254 * Check carefully to make sure that the user has not
255 * modified the state to gain improper privileges or to cause
256 * a machine fault.
257 */
258 /* ARGSUSED */
259 int
compat_16_sys___sigreturn14(struct lwp * l,const struct compat_16_sys___sigreturn14_args * uap,register_t * retval)260 compat_16_sys___sigreturn14(struct lwp *l, const struct compat_16_sys___sigreturn14_args *uap, register_t *retval)
261 {
262 /* {
263 syscallarg(struct sigcontext *) sigcntxp;
264 } */
265 struct sigcontext sc, *scp;
266 struct trapframe *tf;
267 struct proc *p;
268 int error;
269
270 p = l->l_proc;
271
272 /* First ensure consistent stack state (see sendsig). */
273 write_user_windows();
274 if (rwindow_save(l)) {
275 mutex_enter(p->p_lock);
276 sigexit(l, SIGILL);
277 }
278 #ifdef DEBUG
279 if (sigdebug & SDB_FOLLOW)
280 printf("sigreturn: %s[%d], sigcntxp %p\n",
281 p->p_comm, p->p_pid, SCARG(uap, sigcntxp));
282 #endif
283 if ((error = copyin(SCARG(uap, sigcntxp), &sc, sizeof sc)) != 0)
284 return (error);
285 scp = ≻
286
287 tf = l->l_md.md_tf;
288 /*
289 * Only the icc bits in the psr are used, so it need not be
290 * verified. pc and npc must be multiples of 4. This is all
291 * that is required; if it holds, just do it.
292 */
293 if (((scp->sc_pc | scp->sc_npc) & 3) != 0)
294 return (EINVAL);
295
296 /* take only psr ICC field */
297 tf->tf_psr = (tf->tf_psr & ~PSR_ICC) | (scp->sc_psr & PSR_ICC);
298 tf->tf_pc = scp->sc_pc;
299 tf->tf_npc = scp->sc_npc;
300 tf->tf_global[1] = scp->sc_g1;
301 tf->tf_out[0] = scp->sc_o0;
302 tf->tf_out[6] = scp->sc_sp;
303
304 mutex_enter(p->p_lock);
305 if (scp->sc_onstack & SS_ONSTACK)
306 l->l_sigstk.ss_flags |= SS_ONSTACK;
307 else
308 l->l_sigstk.ss_flags &= ~SS_ONSTACK;
309 /* Restore signal mask */
310 (void) sigprocmask1(l, SIG_SETMASK, &scp->sc_mask, 0);
311 mutex_exit(p->p_lock);
312
313 return (EJUSTRETURN);
314 }
315