1 /* $NetBSD: compat_16_machdep.c,v 1.24 2025/04/25 00:26:59 riastradh 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 1.24 2025/04/25 00:26:59 riastradh 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/cpu.h> 61 #include <sys/signal.h> 62 #include <sys/signalvar.h> 63 #include <sys/mount.h> 64 #include <sys/syscallargs.h> 65 66 #include <compat/sys/signal.h> 67 #include <compat/sys/signalvar.h> 68 69 #include <mips/regnum.h> 70 #include <mips/frame.h> 71 #include <mips/locore.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 * const l = curlwp; 95 struct proc * const p = l->l_proc; 96 struct sigacts * const ps = p->p_sigacts; 97 struct pcb * const pcb = lwp_getpcb(l); 98 int onstack, error; 99 struct sigcontext *scp = getframe(l, sig, &onstack, 100 sizeof(*scp), _Alignof(*scp)); 101 struct sigcontext ksc; 102 struct trapframe * const tf = l->l_md.md_utf; 103 sig_t catcher = SIGACTION(p, sig).sa_handler; 104 105 #if !defined(__mips_o32) 106 if (p->p_md.md_abi != _MIPS_BSD_API_O32) 107 sigexit(l, SIGILL); 108 #endif 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 = tf->tf_regs[_R_PC]; 119 ksc.mullo = tf->tf_regs[_R_MULLO]; 120 ksc.mulhi = tf->tf_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], &tf->tf_regs[1], 126 sizeof(ksc.sc_regs) - sizeof(ksc.sc_regs[0])); 127 #else 128 for (size_t i = 1; i < 32; i++) 129 ksc.sc_regs[i] = tf->tf_regs[i]; 130 #endif 131 132 /* Save the FP state, if necessary, then copy it. */ 133 ksc.sc_fpused = fpu_used_p(l); 134 #if !defined(NOFPU) 135 if (ksc.sc_fpused) { 136 /* if FPU has current state, save it first */ 137 fpu_save(l); 138 } 139 #endif 140 *(struct fpreg *)ksc.sc_fpregs = *(struct fpreg *)&pcb->pcb_fpregs; 141 142 /* Save signal stack. */ 143 ksc.sc_onstack = l->l_sigstk.ss_flags & SS_ONSTACK; 144 145 /* Save signal mask. */ 146 ksc.sc_mask = *returnmask; 147 148 #if defined(COMPAT_13) || defined(COMPAT_ULTRIX) 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 native_sigset_to_sigset13(returnmask, &ksc.__sc_mask13); 156 #endif 157 158 sendsig_reset(l, sig); 159 160 mutex_exit(p->p_lock); 161 error = copyout(&ksc, (void *)scp, sizeof(ksc)); 162 mutex_enter(p->p_lock); 163 164 if (error != 0) { 165 /* 166 * Process has trashed its stack; give it an illegal 167 * instruction to halt it in its tracks. 168 */ 169 #ifdef DEBUG 170 if ((sigdebug & SDB_FOLLOW) || 171 ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)) 172 printf("sendsig(%d): copyout failed on sig %d\n", 173 p->p_pid, sig); 174 #endif 175 sigexit(l, SIGILL); 176 /* NOTREACHED */ 177 } 178 179 /* 180 * Set up the registers to directly invoke the signal 181 * handler. The return address will be set up to point 182 * to the signal trampoline to bounce us back. 183 */ 184 tf->tf_regs[_R_A0] = sig; 185 tf->tf_regs[_R_A1] = ksi->ksi_trap; 186 tf->tf_regs[_R_A2] = (intptr_t)scp; 187 tf->tf_regs[_R_A3] = (intptr_t)catcher; /* XXX ??? */ 188 189 tf->tf_regs[_R_PC] = (intptr_t)catcher; 190 tf->tf_regs[_R_T9] = (intptr_t)catcher; 191 tf->tf_regs[_R_SP] = (intptr_t)scp; 192 193 switch (ps->sa_sigdesc[sig].sd_vers) { 194 case __SIGTRAMP_SIGCODE_VERSION: /* legacy on-stack sigtramp */ 195 tf->tf_regs[_R_RA] = (intptr_t)p->p_sigctx.ps_sigcode; 196 break; 197 #ifdef COMPAT_16 198 case __SIGTRAMP_SIGCONTEXT_VERSION: 199 tf->tf_regs[_R_RA] = (intptr_t)ps->sa_sigdesc[sig].sd_tramp; 200 break; 201 #endif 202 default: 203 /* Don't know what trampoline version; kill it. */ 204 sigexit(l, SIGILL); 205 } 206 207 /* Remember that we're now on the signal stack. */ 208 if (onstack) 209 l->l_sigstk.ss_flags |= SS_ONSTACK; 210 211 #ifdef DEBUG 212 if ((sigdebug & SDB_FOLLOW) || 213 ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)) 214 printf("sendsig(%d): sig %d returns\n", 215 p->p_pid, sig); 216 #endif 217 } 218 219 #ifdef COMPAT_16 /* not needed if COMPAT_ULTRIX only */ 220 /* 221 * System call to cleanup state after a signal 222 * has been taken. Reset signal mask and 223 * stack state from context left by sendsig (above). 224 * Return to previous pc and psl as specified by 225 * context left by sendsig. Check carefully to 226 * make sure that the user has not modified the 227 * psl to gain improper privileges or to cause 228 * a machine fault. 229 */ 230 /* ARGSUSED */ 231 int 232 compat_16_sys___sigreturn14(struct lwp *l, const struct compat_16_sys___sigreturn14_args *uap, register_t *retval) 233 { 234 /* { 235 syscallarg(struct sigcontext *) sigcntxp; 236 } */ 237 struct sigcontext *scp, ksc; 238 struct trapframe * const tf = l->l_md.md_utf; 239 struct proc * const p = l->l_proc; 240 struct pcb * const pcb = lwp_getpcb(l); 241 int error; 242 243 #if !defined(__mips_o32) 244 if (p->p_md.md_abi != _MIPS_BSD_API_O32) 245 return ENOSYS; 246 #endif 247 248 /* 249 * The trampoline code hands us the context. 250 * It is unsafe to keep track of it ourselves, in the event that a 251 * program jumps out of a signal handler. 252 */ 253 scp = SCARG(uap, sigcntxp); 254 #ifdef DEBUG 255 if (sigdebug & SDB_FOLLOW) 256 printf("sigreturn: pid %d, scp %p\n", l->l_proc->p_pid, scp); 257 #endif 258 if ((error = copyin(scp, &ksc, sizeof(ksc))) != 0) 259 return (error); 260 261 if ((u_int) ksc.sc_regs[_R_ZERO] != 0xacedbadeU)/* magic number */ 262 return (EINVAL); 263 264 /* Restore the register context. */ 265 tf->tf_regs[_R_PC] = ksc.sc_pc; 266 tf->tf_regs[_R_MULLO] = ksc.mullo; 267 tf->tf_regs[_R_MULHI] = ksc.mulhi; 268 #if defined(__mips_o32) 269 memcpy(&tf->tf_regs[1], &scp->sc_regs[1], 270 sizeof(scp->sc_regs) - sizeof(scp->sc_regs[0])); 271 #else 272 for (size_t i = 1; i < __arraycount(ksc.sc_regs); i++) 273 tf->tf_regs[i] = ksc.sc_regs[i]; 274 #endif 275 #if !defined(NOFPU) 276 if (scp->sc_fpused) { 277 fpu_discard(l); 278 } 279 #endif 280 *(struct fpreg *)&pcb->pcb_fpregs = *(struct fpreg *)scp->sc_fpregs; 281 282 mutex_enter(p->p_lock); 283 /* Restore signal stack. */ 284 if (ksc.sc_onstack & SS_ONSTACK) 285 l->l_sigstk.ss_flags |= SS_ONSTACK; 286 else 287 l->l_sigstk.ss_flags &= ~SS_ONSTACK; 288 /* Restore signal mask. */ 289 (void) sigprocmask1(l, SIG_SETMASK, &ksc.sc_mask, 0); 290 mutex_exit(p->p_lock); 291 292 return (EJUSTRETURN); 293 } 294 #endif /* COMPAT_16 */ 295
Indexes created Sun Oct 25 00:26:45 UTC 2026