1 /* $NetBSD: compat_16_machdep.c,v 1.17 2011/01/14 02:06:28 rmind 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 1.17 2011/01/14 02:06:28 rmind 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/pcb.h> 73 #include <mips/reg.h> 74 75 #if !defined(__mips_o32) 76 #define fpreg fpreg_oabi 77 #endif 78 79 #ifdef DEBUG 80 int sigdebug = 0; 81 int sigpid = 0; 82 #define SDB_FOLLOW 0x01 83 #define SDB_KSTACK 0x02 84 #define SDB_FPSTATE 0x04 85 #endif 86 87 /* 88 * Send a signal to process. 89 */ 90 void 91 sendsig_sigcontext(const ksiginfo_t *ksi, const sigset_t *returnmask) 92 { 93 int sig = ksi->ksi_signo; 94 struct lwp *l = curlwp; 95 struct proc *p = l->l_proc; 96 struct pcb *pcb; 97 struct sigacts *ps = p->p_sigacts; 98 int onstack, error; 99 struct sigcontext *scp = getframe(l, sig, &onstack); 100 struct sigcontext ksc; 101 struct frame *f = l->l_md.md_regs; 102 sig_t catcher = SIGACTION(p, sig).sa_handler; 103 104 #if !defined(__mips_o32) 105 if (p->p_md.md_abi != _MIPS_BSD_API_O32) 106 sigexit(l, SIGILL); 107 #endif 108 109 scp--; 110 111 #ifdef DEBUG 112 if ((sigdebug & SDB_FOLLOW) || 113 ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)) 114 printf("sendsig(%d): sig %d ssp %p scp %p\n", 115 p->p_pid, sig, &onstack, scp); 116 #endif 117 118 /* Build stack frame for signal trampoline. */ 119 ksc.sc_pc = f->f_regs[_R_PC]; 120 ksc.mullo = f->f_regs[_R_MULLO]; 121 ksc.mulhi = f->f_regs[_R_MULHI]; 122 123 /* Save register context. */ 124 ksc.sc_regs[_R_ZERO] = 0xACEDBADE; /* magic number */ 125 #if defined(__mips_o32) 126 memcpy(&ksc.sc_regs[1], &f->f_regs[1], 127 sizeof(ksc.sc_regs) - sizeof(ksc.sc_regs[0])); 128 #else 129 size_t i; 130 for (i = 1; i < 32; i++) 131 ksc.sc_regs[i] = f->f_regs[i]; 132 #endif 133 134 /* Save the FP state, if necessary, then copy it. */ 135 pcb = lwp_getpcb(l); 136 #ifndef SOFTFLOAT 137 ksc.sc_fpused = l->l_md.md_flags & MDP_FPUSED; 138 if (ksc.sc_fpused) { 139 /* if FPU has current state, save it first */ 140 savefpregs(l); 141 } 142 #endif 143 *(struct fpreg *)ksc.sc_fpregs = *(struct fpreg *)&pcb->pcb_fpregs; 144 145 /* Save signal stack. */ 146 ksc.sc_onstack = l->l_sigstk.ss_flags & SS_ONSTACK; 147 148 /* Save signal mask. */ 149 ksc.sc_mask = *returnmask; 150 151 #if defined(COMPAT_13) || defined(COMPAT_ULTRIX) 152 /* 153 * XXX We always have to save an old style signal mask because 154 * XXX we might be delivering a signal to a process which will 155 * XXX escape from the signal in a non-standard way and invoke 156 * XXX sigreturn() directly. 157 */ 158 native_sigset_to_sigset13(returnmask, &ksc.__sc_mask13); 159 #endif 160 161 sendsig_reset(l, sig); 162 163 mutex_exit(p->p_lock); 164 error = copyout(&ksc, (void *)scp, sizeof(ksc)); 165 mutex_enter(p->p_lock); 166 167 if (error != 0) { 168 /* 169 * Process has trashed its stack; give it an illegal 170 * instruction to halt it in its tracks. 171 */ 172 #ifdef DEBUG 173 if ((sigdebug & SDB_FOLLOW) || 174 ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)) 175 printf("sendsig(%d): copyout failed on sig %d\n", 176 p->p_pid, sig); 177 #endif 178 sigexit(l, SIGILL); 179 /* NOTREACHED */ 180 } 181 182 /* 183 * Set up the registers to directly invoke the signal 184 * handler. The return address will be set up to point 185 * to the signal trampoline to bounce us back. 186 */ 187 f->f_regs[_R_A0] = sig; 188 f->f_regs[_R_A1] = ksi->ksi_trap; 189 f->f_regs[_R_A2] = (intptr_t)scp; 190 f->f_regs[_R_A3] = (intptr_t)catcher; /* XXX ??? */ 191 192 f->f_regs[_R_PC] = (intptr_t)catcher; 193 f->f_regs[_R_T9] = (intptr_t)catcher; 194 f->f_regs[_R_SP] = (intptr_t)scp; 195 196 switch (ps->sa_sigdesc[sig].sd_vers) { 197 case 0: /* legacy on-stack sigtramp */ 198 f->f_regs[_R_RA] = (intptr_t)p->p_sigctx.ps_sigcode; 199 break; 200 #ifdef COMPAT_16 201 case 1: 202 f->f_regs[_R_RA] = (intptr_t)ps->sa_sigdesc[sig].sd_tramp; 203 break; 204 #endif 205 default: 206 /* Don't know what trampoline version; kill it. */ 207 sigexit(l, SIGILL); 208 } 209 210 /* Remember that we're now on the signal stack. */ 211 if (onstack) 212 l->l_sigstk.ss_flags |= SS_ONSTACK; 213 214 #ifdef DEBUG 215 if ((sigdebug & SDB_FOLLOW) || 216 ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)) 217 printf("sendsig(%d): sig %d returns\n", 218 p->p_pid, sig); 219 #endif 220 } 221 222 #ifdef COMPAT_16 /* not needed if COMPAT_ULTRIX only */ 223 /* 224 * System call to cleanup state after a signal 225 * has been taken. Reset signal mask and 226 * stack state from context left by sendsig (above). 227 * Return to previous pc and psl as specified by 228 * context left by sendsig. Check carefully to 229 * make sure that the user has not modified the 230 * psl to gain improper privileges or to cause 231 * a machine fault. 232 */ 233 /* ARGSUSED */ 234 int 235 compat_16_sys___sigreturn14(struct lwp *l, const struct compat_16_sys___sigreturn14_args *uap, register_t *retval) 236 { 237 /* { 238 syscallarg(struct sigcontext *) sigcntxp; 239 } */ 240 struct sigcontext *scp, ksc; 241 struct frame *f; 242 struct proc *p = l->l_proc; 243 struct pcb *pcb; 244 int error; 245 246 #if !defined(__mips_o32) 247 if (p->p_md.md_abi != _MIPS_BSD_API_O32) 248 return ENOSYS; 249 #endif 250 251 /* 252 * The trampoline code hands us the context. 253 * It is unsafe to keep track of it ourselves, in the event that a 254 * program jumps out of a signal handler. 255 */ 256 scp = SCARG(uap, sigcntxp); 257 #ifdef DEBUG 258 if (sigdebug & SDB_FOLLOW) 259 printf("sigreturn: pid %d, scp %p\n", l->l_proc->p_pid, scp); 260 #endif 261 if ((error = copyin(scp, &ksc, sizeof(ksc))) != 0) 262 return (error); 263 264 if ((u_int) ksc.sc_regs[_R_ZERO] != 0xacedbadeU)/* magic number */ 265 return (EINVAL); 266 267 /* Restore the register context. */ 268 f = l->l_md.md_regs; 269 f->f_regs[_R_PC] = ksc.sc_pc; 270 f->f_regs[_R_MULLO] = ksc.mullo; 271 f->f_regs[_R_MULHI] = ksc.mulhi; 272 #if defined(__mips_o32) 273 memcpy(&f->f_regs[1], &scp->sc_regs[1], 274 sizeof(scp->sc_regs) - sizeof(scp->sc_regs[0])); 275 276 #else 277 size_t i; 278 for (i = 1; i < __arraycount(f->f_regs); i++) 279 f->f_regs[i] = ksc.sc_regs[i]; 280 #endif 281 #ifndef SOFTFLOAT 282 if (scp->sc_fpused) { 283 /* Disable the FPU to fault in FP registers. */ 284 f->f_regs[_R_SR] &= ~MIPS_SR_COP_1_BIT; 285 fpcurlwp = &lwp0; 286 } 287 #endif 288 pcb = lwp_getpcb(l); 289 *(struct fpreg *)&pcb->pcb_fpregs = *(struct fpreg *)scp->sc_fpregs; 290 291 mutex_enter(p->p_lock); 292 /* Restore signal stack. */ 293 if (ksc.sc_onstack & SS_ONSTACK) 294 l->l_sigstk.ss_flags |= SS_ONSTACK; 295 else 296 l->l_sigstk.ss_flags &= ~SS_ONSTACK; 297 /* Restore signal mask. */ 298 (void) sigprocmask1(l, SIG_SETMASK, &ksc.sc_mask, 0); 299 mutex_exit(p->p_lock); 300 301 return (EJUSTRETURN); 302 } 303 #endif /* COMPAT_16 */ 304