1 /* $NetBSD: sig_machdep.c,v 1.22 2011/04/29 22:09:41 matt 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 Christos Zoulas. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> /* RCS ID & Copyright macro defns */ 33 34 __KERNEL_RCSID(0, "$NetBSD: sig_machdep.c,v 1.22 2011/04/29 22:09:41 matt Exp $"); 35 36 #include "opt_cputype.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/kernel.h> 41 #include <sys/proc.h> 42 #include <sys/signal.h> 43 #include <sys/signalvar.h> 44 #include <sys/mount.h> 45 #include <sys/syscallargs.h> 46 47 #include <machine/cpu.h> 48 49 #include <mips/frame.h> 50 #include <mips/regnum.h> 51 #include <mips/locore.h> 52 53 void * 54 getframe(struct lwp *l, int sig, int *onstack) 55 { 56 struct proc * const p = l->l_proc; 57 struct trapframe * const tf = l->l_md.md_utf; 58 59 /* Do we need to jump onto the signal stack? */ 60 *onstack = (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 61 && (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0; 62 if (*onstack) 63 return (char *)l->l_sigstk.ss_sp + l->l_sigstk.ss_size; 64 return (void *)(intptr_t)tf->tf_regs[_R_SP]; 65 } 66 67 struct sigframe_siginfo { 68 siginfo_t sf_si; 69 ucontext_t sf_uc; 70 }; 71 72 /* 73 * Send a signal to process. 74 */ 75 void 76 sendsig_siginfo(const ksiginfo_t *ksi, const sigset_t *mask) 77 { 78 struct lwp * const l = curlwp; 79 struct proc * const p = l->l_proc; 80 struct sigacts * const sa = p->p_sigacts; 81 struct trapframe * const tf = l->l_md.md_utf; 82 int onstack, error; 83 const int signo = ksi->ksi_signo; 84 struct sigframe_siginfo *sf = getframe(l, signo, &onstack); 85 struct sigframe_siginfo ksf; 86 const sig_t catcher = SIGACTION(p, signo).sa_handler; 87 88 sf--; 89 90 ksf.sf_si._info = ksi->ksi_info; 91 ksf.sf_uc.uc_flags = _UC_SIGMASK 92 | (l->l_sigstk.ss_flags & SS_ONSTACK ? _UC_SETSTACK : _UC_CLRSTACK); 93 ksf.sf_uc.uc_sigmask = *mask; 94 ksf.sf_uc.uc_link = l->l_ctxlink; 95 memset(&ksf.sf_uc.uc_stack, 0, sizeof(ksf.sf_uc.uc_stack)); 96 sendsig_reset(l, signo); 97 98 mutex_exit(p->p_lock); 99 cpu_getmcontext(l, &ksf.sf_uc.uc_mcontext, &ksf.sf_uc.uc_flags); 100 error = copyout(&ksf, sf, sizeof(ksf)); 101 mutex_enter(p->p_lock); 102 103 if (error != 0) { 104 /* 105 * Process has trashed its stack; give it an illegal 106 * instruction to halt it in its tracks. 107 */ 108 sigexit(l, SIGILL); 109 /* NOTREACHED */ 110 } 111 112 /* 113 * Set up the registers to directly invoke the signal 114 * handler. The return address will be set up to point 115 * to the signal trampoline to bounce us back. 116 */ 117 tf->tf_regs[_R_A0] = signo; 118 tf->tf_regs[_R_A1] = (intptr_t)&sf->sf_si; 119 tf->tf_regs[_R_A2] = (intptr_t)&sf->sf_uc; 120 121 tf->tf_regs[_R_PC] = (intptr_t)catcher; 122 tf->tf_regs[_R_T9] = (intptr_t)catcher; 123 tf->tf_regs[_R_SP] = (intptr_t)sf; 124 tf->tf_regs[_R_RA] = (intptr_t)sa->sa_sigdesc[signo].sd_tramp; 125 126 /* Remember that we're now on the signal stack. */ 127 if (onstack) 128 l->l_sigstk.ss_flags |= SS_ONSTACK; 129 } 130