1 /* $NetBSD: compat_16_machdep.c,v 1.23 2021/10/27 04:14:59 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 2003 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 and by Chris G. Demetriou.
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) 1994, 1995, 1996 Carnegie-Mellon University.
35 * All rights reserved.
36 *
37 * Author: Chris G. Demetriou
38 *
39 * Permission to use, copy, modify and distribute this software and
40 * its documentation is hereby granted, provided that both the copyright
41 * notice and this permission notice appear in all copies of the
42 * software, derivative works or modified versions, and any portions
43 * thereof, and that both notices appear in supporting documentation.
44 *
45 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
46 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
47 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
48 *
49 * Carnegie Mellon requests users of this software to return to
50 *
51 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
52 * School of Computer Science
53 * Carnegie Mellon University
54 * Pittsburgh PA 15213-3890
55 *
56 * any improvements or extensions that they make and grant Carnegie the
57 * rights to redistribute these changes.
58 */
59
60 #ifdef _KERNEL_OPT
61 #include "opt_ddb.h"
62 #include "opt_kgdb.h"
63 #include "opt_multiprocessor.h"
64 #include "opt_dec_3000_300.h"
65 #include "opt_dec_3000_500.h"
66 #include "opt_compat_netbsd.h"
67 #include "opt_execfmt.h"
68 #endif /* _KERNEL_OPT */
69
70 #include <sys/cdefs.h> /* RCS ID & Copyright macro defns */
71 #include <sys/types.h>
72 #include <sys/param.h>
73 #include <sys/signal.h>
74 #include <sys/mount.h>
75 #include <sys/proc.h>
76 #include <sys/systm.h>
77 #include <sys/syscall.h>
78 #include <sys/syscallargs.h>
79
80 #if defined(COMPAT_13)
81 #include <compat/sys/signal.h>
82 #include <compat/sys/signalvar.h>
83 #endif
84
85 #include <machine/cpu.h>
86 #include <machine/reg.h>
87
88 __KERNEL_RCSID(0, "$NetBSD: compat_16_machdep.c,v 1.23 2021/10/27 04:14:59 thorpej Exp $");
89
90
91 #ifdef DEBUG
92 #include <machine/sigdebug.h>
93 #endif
94
95 #include <machine/alpha.h>
96
97 #include <sys/ksyms.h>
98
99 /*
100 * Send an interrupt to process, old style
101 */
102 void
sendsig_sigcontext(const ksiginfo_t * ksi,const sigset_t * mask)103 sendsig_sigcontext(const ksiginfo_t *ksi, const sigset_t *mask)
104 {
105 struct lwp *l = curlwp;
106 struct proc *p = l->l_proc;
107 struct pcb *pcb = lwp_getpcb(l);
108 struct sigacts *ps = p->p_sigacts;
109 int onstack, sig = ksi->ksi_signo, error;
110 struct sigframe_sigcontext *fp, frame;
111 struct trapframe *tf;
112 sig_t catcher = SIGACTION(p, sig).sa_handler;
113
114 tf = l->l_md.md_tf;
115 fp = getframe(l, sig, &onstack);
116 fp--;
117
118 #ifdef DEBUG
119 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
120 printf("sendsig_sigcontext(%d): sig %d ssp %p usp %p\n",
121 p->p_pid, sig, &onstack, fp);
122 #endif
123
124 /* Build stack frame for signal trampoline. */
125 frame.sf_sc.sc_pc = tf->tf_regs[FRAME_PC];
126 frame.sf_sc.sc_ps = tf->tf_regs[FRAME_PS];
127
128 /* Save register context. */
129 frametoreg(tf, (struct reg *)frame.sf_sc.sc_regs);
130 frame.sf_sc.sc_regs[R_ZERO] = 0xACEDBADE; /* magic number */
131 frame.sf_sc.sc_regs[R_SP] = alpha_pal_rdusp();
132
133 /* save the floating-point state, if necessary, then copy it. */
134 fpu_save(l);
135 frame.sf_sc.sc_ownedfp = fpu_valid_p(l);
136 memcpy((struct fpreg *)frame.sf_sc.sc_fpregs, &pcb->pcb_fp,
137 sizeof(struct fpreg));
138 frame.sf_sc.sc_fp_control = alpha_read_fp_c(l);
139 memset(frame.sf_sc.sc_reserved, 0, sizeof frame.sf_sc.sc_reserved);
140 memset(frame.sf_sc.sc_xxx, 0, sizeof frame.sf_sc.sc_xxx); /* XXX */
141
142 /* Save signal stack. */
143 frame.sf_sc.sc_onstack = l->l_sigstk.ss_flags & SS_ONSTACK;
144
145 /* Save signal mask. */
146 frame.sf_sc.sc_mask = *mask;
147
148 #if defined(COMPAT_13)
149 /*
150 * XXX We always have to save an old style signal mask because
151 * XXX we might be delivering a signal to a process which will
152 * XXX escape from the signal in a non-standard way and invoke
153 * XXX sigreturn() directly.
154 */
155 {
156 /* Note: it's a long in the stack frame. */
157 sigset13_t mask13;
158
159 native_sigset_to_sigset13(mask, &mask13);
160 frame.sf_sc.__sc_mask13 = mask13;
161 }
162 #endif
163
164 sendsig_reset(l, sig);
165 mutex_exit(p->p_lock);
166 error = copyout(&frame, (void *)fp, sizeof(frame));
167 mutex_enter(p->p_lock);
168
169 if (error != 0) {
170 /*
171 * Process has trashed its stack; give it an illegal
172 * instruction to halt it in its tracks.
173 */
174 #ifdef DEBUG
175 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
176 printf("sendsig_sigcontext(%d): copyout failed on sig %d\n",
177 p->p_pid, sig);
178 #endif
179 sigexit(l, SIGILL);
180 /* NOTREACHED */
181 }
182 #ifdef DEBUG
183 if (sigdebug & SDB_FOLLOW)
184 printf("sendsig_sigcontext(%d): sig %d usp %p code %x\n",
185 p->p_pid, sig, fp, ksi->ksi_code);
186 #endif
187
188 /*
189 * Set up the registers to directly invoke the signal handler. The
190 * signal trampoline is then used to return from the signal. Note
191 * the trampoline version numbers are coordinated with machine-
192 * dependent code in libc.
193 */
194 switch (ps->sa_sigdesc[sig].sd_vers) {
195 case __SIGTRAMP_SIGCODE_VERSION: /* legacy on-stack sigtramp */
196 buildcontext(l,(void *)catcher,
197 (void *)p->p_sigctx.ps_sigcode,
198 (void *)fp);
199 break;
200 #ifdef COMPAT_16
201 case __SIGTRAMP_SIGCONTEXT_VERSION:
202 buildcontext(l,(void *)catcher,
203 (const void *)ps->sa_sigdesc[sig].sd_tramp,
204 (void *)fp);
205 break;
206 #endif
207 default:
208 /* Don't know what trampoline version; kill it. */
209 sigexit(l, SIGILL);
210 }
211
212 /* sigcontext specific trap frame */
213 tf->tf_regs[FRAME_A0] = sig;
214
215 /* tf->tf_regs[FRAME_A1] = ksi->ksi_code; */
216 tf->tf_regs[FRAME_A1] = KSI_TRAPCODE(ksi);
217 tf->tf_regs[FRAME_A2] = (uint64_t)&fp->sf_sc;
218
219 /* Remember that we're now on the signal stack. */
220 if (onstack)
221 l->l_sigstk.ss_flags |= SS_ONSTACK;
222
223 #ifdef DEBUG
224 if (sigdebug & SDB_FOLLOW)
225 printf("sendsig(%d): pc %lx, catcher %lx\n", p->p_pid,
226 tf->tf_regs[FRAME_PC], tf->tf_regs[FRAME_A3]);
227 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
228 printf("sendsig(%d): sig %d returns\n",
229 p->p_pid, sig);
230 #endif
231 }
232
233 #ifdef COMPAT_16
234 /*
235 * System call to cleanup state after a signal
236 * has been taken. Reset signal mask and
237 * stack state from context left by sendsig (above).
238 * Return to previous pc and psl as specified by
239 * context left by sendsig. Check carefully to
240 * make sure that the user has not modified the
241 * psl to gain improper privileges or to cause
242 * a machine fault.
243 */
244 /* ARGSUSED */
245 int
compat_16_sys___sigreturn14(struct lwp * l,const struct compat_16_sys___sigreturn14_args * uap,register_t * retval)246 compat_16_sys___sigreturn14(struct lwp *l, const struct compat_16_sys___sigreturn14_args *uap, register_t *retval)
247 {
248 /* {
249 syscallarg(struct sigcontext *) sigcntxp;
250 } */
251 struct sigcontext *scp, ksc;
252 struct proc *p = l->l_proc;
253 struct pcb *pcb;
254
255 /*
256 * The trampoline code hands us the context.
257 * It is unsafe to keep track of it ourselves, in the event that a
258 * program jumps out of a signal handler.
259 */
260 scp = SCARG(uap, sigcntxp);
261 #ifdef DEBUG
262 if (sigdebug & SDB_FOLLOW)
263 printf("sigreturn: pid %d, scp %p\n", p->p_pid, scp);
264 #endif
265 if (ALIGN(scp) != (uint64_t)scp)
266 return (EINVAL);
267
268 if (copyin((void *)scp, &ksc, sizeof(ksc)) != 0)
269 return (EFAULT);
270
271 if (ksc.sc_regs[R_ZERO] != 0xACEDBADE) /* magic number */
272 return (EINVAL);
273
274 /* Restore register context. */
275 l->l_md.md_tf->tf_regs[FRAME_PC] = ksc.sc_pc;
276 l->l_md.md_tf->tf_regs[FRAME_PS] =
277 (ksc.sc_ps | ALPHA_PSL_USERSET) & ~ALPHA_PSL_USERCLR;
278
279 regtoframe((struct reg *)ksc.sc_regs, l->l_md.md_tf);
280 alpha_pal_wrusp(ksc.sc_regs[R_SP]);
281
282 pcb = lwp_getpcb(l);
283 fpu_discard(l, true);
284 memcpy(&pcb->pcb_fp, (struct fpreg *)ksc.sc_fpregs,
285 sizeof(struct fpreg));
286 pcb->pcb_fp.fpr_cr = ksc.sc_fpcr;
287 l->l_md.md_flags = ksc.sc_fp_control & MDLWP_FP_C;
288
289 mutex_enter(p->p_lock);
290 /* Restore signal stack. */
291 if (ksc.sc_onstack & SS_ONSTACK)
292 l->l_sigstk.ss_flags |= SS_ONSTACK;
293 else
294 l->l_sigstk.ss_flags &= ~SS_ONSTACK;
295 /* Restore signal mask. */
296 (void) sigprocmask1(l, SIG_SETMASK, &ksc.sc_mask, 0);
297 mutex_exit(p->p_lock);
298
299 #ifdef DEBUG
300 if (sigdebug & SDB_FOLLOW)
301 printf("sigreturn(%d): returns\n", p->p_pid);
302 #endif
303 return (EJUSTRETURN);
304 }
305 #endif /* COMPAT_16 */
306