1 /* $NetBSD: compat_16_machdep.c,v 1.16 2009/12/14 12:53:18 uebayasi Exp $ */ 2 3 /*- 4 * Copyright (c) 1998, 2001 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 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 1996 The Board of Trustees of The Leland Stanford 35 * Junior University. All Rights Reserved. 36 * 37 * Permission to use, copy, modify, and distribute this 38 * software and its documentation for any purpose and without 39 * fee is hereby granted, provided that the above copyright 40 * notice appear in all copies. Stanford University 41 * makes no representations about the suitability of this 42 * software for any purpose. It is provided "as is" without 43 * express or implied warranty. 44 */ 45 46 #include <sys/cdefs.h> /* RCS ID & Copyright macro defns */ 47 48 __KERNEL_RCSID(0, "$NetBSD: compat_16_machdep.c,v 1.16 2009/12/14 12:53:18 uebayasi Exp $"); 49 50 #ifdef _KERNEL_OPT 51 #include "opt_cputype.h" 52 #include "opt_compat_netbsd.h" 53 #include "opt_compat_ultrix.h" 54 #endif 55 56 #include <sys/param.h> 57 #include <sys/systm.h> 58 #include <sys/kernel.h> 59 #include <sys/proc.h> 60 #include <sys/signal.h> 61 #include <sys/signalvar.h> 62 #include <sys/mount.h> 63 #include <sys/syscallargs.h> 64 65 #include <compat/sys/signal.h> 66 #include <compat/sys/signalvar.h> 67 68 #include <machine/cpu.h> 69 70 #include <mips/regnum.h> 71 #include <mips/frame.h> 72 #include <mips/reg.h> 73 74 #if !defined(__mips_o32) 75 #define fpreg fpreg_oabi 76 #endif 77 78 #ifdef DEBUG 79 int sigdebug = 0; 80 int sigpid = 0; 81 #define SDB_FOLLOW 0x01 82 #define SDB_KSTACK 0x02 83 #define SDB_FPSTATE 0x04 84 #endif 85 86 /* 87 * Send a signal to process. 88 */ 89 void 90 sendsig_sigcontext(const ksiginfo_t *ksi, const sigset_t *returnmask) 91 { 92 int sig = ksi->ksi_signo; 93 struct lwp *l = curlwp; 94 struct proc *p = l->l_proc; 95 struct pcb *pcb; 96 struct sigacts *ps = p->p_sigacts; 97 int onstack, error; 98 struct sigcontext *scp = getframe(l, sig, &onstack); 99 struct sigcontext ksc; 100 struct frame *f = l->l_md.md_regs; 101 sig_t catcher = SIGACTION(p, sig).sa_handler; 102 103 #if !defined(__mips_o32) 104 if (p->p_md.md_abi != _MIPS_BSD_API_O32) 105 sigexit(l, SIGILL); 106 #endif 107 108 scp--; 109 110 #ifdef DEBUG 111 if ((sigdebug & SDB_FOLLOW) || 112 ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)) 113 printf("sendsig(%d): sig %d ssp %p scp %p\n", 114 p->p_pid, sig, &onstack, scp); 115 #endif 116 117 /* Build stack frame for signal trampoline. */ 118 ksc.sc_pc = f->f_regs[_R_PC]; 119 ksc.mullo = f->f_regs[_R_MULLO]; 120 ksc.mulhi = f->f_regs[_R_MULHI]; 121 122 /* Save register context. */ 123 ksc.sc_regs[_R_ZERO] = 0xACEDBADE; /* magic number */ 124 #if defined(__mips_o32) 125 memcpy(&ksc.sc_regs[1], &f->f_regs[1], 126 sizeof(ksc.sc_regs) - sizeof(ksc.sc_regs[0])); 127 #else 128 size_t i; 129 for (i = 1; i < 32; i++) 130 ksc.sc_regs[i] = f->f_regs[i]; 131 #endif 132 133 /* Save the FP state, if necessary, then copy it. */ 134 pcb = lwp_getpcb(l); 135 #ifndef SOFTFLOAT 136 ksc.sc_fpused = l->l_md.md_flags & MDP_FPUSED; 137 if (ksc.sc_fpused) { 138 /* if FPU has current state, save it first */ 139 savefpregs(l); 140 } 141 #endif 142 *(struct fpreg *)ksc.sc_fpregs = *(struct fpreg *)&pcb->pcb_fpregs; 143 144 /* Save signal stack. */ 145 ksc.sc_onstack = l->l_sigstk.ss_flags & SS_ONSTACK; 146 147 /* Save signal mask. */ 148 ksc.sc_mask = *returnmask; 149 150 #if defined(COMPAT_13) || defined(COMPAT_ULTRIX) 151 /* 152 * XXX We always have to save an old style signal mask because 153 * XXX we might be delivering a signal to a process which will 154 * XXX escape from the signal in a non-standard way and invoke 155 * XXX sigreturn() directly. 156 */ 157 native_sigset_to_sigset13(returnmask, &ksc.__sc_mask13); 158 #endif 159 160 sendsig_reset(l, sig); 161 162 mutex_exit(p->p_lock); 163 error = copyout(&ksc, (void *)scp, sizeof(ksc)); 164 mutex_enter(p->p_lock); 165 166 if (error != 0) { 167 /* 168 * Process has trashed its stack; give it an illegal 169 * instruction to halt it in its tracks. 170 */ 171 #ifdef DEBUG 172 if ((sigdebug & SDB_FOLLOW) || 173 ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)) 174 printf("sendsig(%d): copyout failed on sig %d\n", 175 p->p_pid, sig); 176 #endif 177 sigexit(l, SIGILL); 178 /* NOTREACHED */ 179 } 180 181 /* 182 * Set up the registers to directly invoke the signal 183 * handler. The return address will be set up to point 184 * to the signal trampoline to bounce us back. 185 */ 186 f->f_regs[_R_A0] = sig; 187 f->f_regs[_R_A1] = ksi->ksi_trap; 188 f->f_regs[_R_A2] = (intptr_t)scp; 189 f->f_regs[_R_A3] = (intptr_t)catcher; /* XXX ??? */ 190 191 f->f_regs[_R_PC] = (intptr_t)catcher; 192 f->f_regs[_R_T9] = (intptr_t)catcher; 193 f->f_regs[_R_SP] = (intptr_t)scp; 194 195 switch (ps->sa_sigdesc[sig].sd_vers) { 196 case 0: /* legacy on-stack sigtramp */ 197 f->f_regs[_R_RA] = (intptr_t)p->p_sigctx.ps_sigcode; 198 break; 199 #ifdef COMPAT_16 200 case 1: 201 f->f_regs[_R_RA] = (intptr_t)ps->sa_sigdesc[sig].sd_tramp; 202 break; 203 #endif 204 default: 205 /* Don't know what trampoline version; kill it. */ 206 sigexit(l, SIGILL); 207 } 208 209 /* Remember that we're now on the signal stack. */ 210 if (onstack) 211 l->l_sigstk.ss_flags |= SS_ONSTACK; 212 213 #ifdef DEBUG 214 if ((sigdebug & SDB_FOLLOW) || 215 ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)) 216 printf("sendsig(%d): sig %d returns\n", 217 p->p_pid, sig); 218 #endif 219 } 220 221 #ifdef COMPAT_16 /* not needed if COMPAT_ULTRIX only */ 222 /* 223 * System call to cleanup state after a signal 224 * has been taken. Reset signal mask and 225 * stack state from context left by sendsig (above). 226 * Return to previous pc and psl as specified by 227 * context left by sendsig. Check carefully to 228 * make sure that the user has not modified the 229 * psl to gain improper privileges or to cause 230 * a machine fault. 231 */ 232 /* ARGSUSED */ 233 int 234 compat_16_sys___sigreturn14(struct lwp *l, const struct compat_16_sys___sigreturn14_args *uap, register_t *retval) 235 { 236 /* { 237 syscallarg(struct sigcontext *) sigcntxp; 238 } */ 239 struct sigcontext *scp, ksc; 240 struct frame *f; 241 struct proc *p = l->l_proc; 242 struct pcb *pcb; 243 int error; 244 245 #if !defined(__mips_o32) 246 if (p->p_md.md_abi != _MIPS_BSD_API_O32) 247 return ENOSYS; 248 #endif 249 250 /* 251 * The trampoline code hands us the context. 252 * It is unsafe to keep track of it ourselves, in the event that a 253 * program jumps out of a signal handler. 254 */ 255 scp = SCARG(uap, sigcntxp); 256 #ifdef DEBUG 257 if (sigdebug & SDB_FOLLOW) 258 printf("sigreturn: pid %d, scp %p\n", l->l_proc->p_pid, scp); 259 #endif 260 if ((error = copyin(scp, &ksc, sizeof(ksc))) != 0) 261 return (error); 262 263 if ((u_int) ksc.sc_regs[_R_ZERO] != 0xacedbadeU)/* magic number */ 264 return (EINVAL); 265 266 /* Restore the register context. */ 267 f = l->l_md.md_regs; 268 f->f_regs[_R_PC] = ksc.sc_pc; 269 f->f_regs[_R_MULLO] = ksc.mullo; 270 f->f_regs[_R_MULHI] = ksc.mulhi; 271 #if defined(__mips_o32) 272 memcpy(&f->f_regs[1], &scp->sc_regs[1], 273 sizeof(scp->sc_regs) - sizeof(scp->sc_regs[0])); 274 275 #else 276 size_t i; 277 for (i = 1; i < __arraycount(f->f_regs); i++) 278 f->f_regs[i] = ksc.sc_regs[i]; 279 #endif 280 #ifndef SOFTFLOAT 281 if (scp->sc_fpused) { 282 /* Disable the FPU to fault in FP registers. */ 283 f->f_regs[_R_SR] &= ~MIPS_SR_COP_1_BIT; 284 fpcurlwp = &lwp0; 285 } 286 #endif 287 pcb = lwp_getpcb(l); 288 *(struct fpreg *)&pcb->pcb_fpregs = *(struct fpreg *)scp->sc_fpregs; 289 290 mutex_enter(p->p_lock); 291 /* Restore signal stack. */ 292 if (ksc.sc_onstack & SS_ONSTACK) 293 l->l_sigstk.ss_flags |= SS_ONSTACK; 294 else 295 l->l_sigstk.ss_flags &= ~SS_ONSTACK; 296 /* Restore signal mask. */ 297 (void) sigprocmask1(l, SIG_SETMASK, &ksc.sc_mask, 0); 298 mutex_exit(p->p_lock); 299 300 return (EJUSTRETURN); 301 } 302 #endif /* COMPAT_16 */ 303