1 /* $NetBSD: sig_machdep.c,v 1.17 2008/11/19 18:35:59 ad 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 1.17 2008/11/19 18:35:59 ad 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/user.h> 43 #include <sys/signal.h> 44 #include <sys/signalvar.h> 45 #include <sys/mount.h> 46 #include <sys/syscallargs.h> 47 48 #include <machine/cpu.h> 49 50 #include <mips/frame.h> 51 #include <mips/regnum.h> 52 53 void * 54 getframe(struct lwp *l, int sig, int *onstack) 55 { 56 struct proc *p = l->l_proc; 57 struct frame *fp = l->l_md.md_regs; 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 else 65 return (void *)fp->f_regs[_R_SP]; 66 } 67 68 struct sigframe_siginfo { 69 siginfo_t sf_si; 70 ucontext_t sf_uc; 71 }; 72 73 /* 74 * Send a signal to process. 75 */ 76 void 77 sendsig_siginfo(const ksiginfo_t *ksi, const sigset_t *mask) 78 { 79 struct lwp *l = curlwp; 80 struct proc *p = l->l_proc; 81 struct sigacts *ps = p->p_sigacts; 82 int onstack, error; 83 int sig = ksi->ksi_signo; 84 struct sigframe_siginfo *fp = getframe(l, sig, &onstack); 85 struct frame *tf; 86 ucontext_t uc; 87 size_t ucsz; 88 sig_t catcher = SIGACTION(p, sig).sa_handler; 89 90 tf = (struct frame *)l->l_md.md_regs; 91 fp--; 92 93 uc.uc_flags = _UC_SIGMASK 94 | ((l->l_sigstk.ss_flags & SS_ONSTACK) 95 ? _UC_SETSTACK : _UC_CLRSTACK); 96 uc.uc_sigmask = *mask; 97 uc.uc_link = l->l_ctxlink; 98 memset(&uc.uc_stack, 0, sizeof(uc.uc_stack)); 99 ucsz = (char *)&uc.__uc_pad - (char *)&uc; 100 sendsig_reset(l, sig); 101 mutex_exit(p->p_lock); 102 cpu_getmcontext(l, &uc.uc_mcontext, &uc.uc_flags); 103 error = copyout(&ksi->ksi_info, &fp->sf_si, sizeof(ksi->ksi_info)); 104 if (error == 0) 105 error = copyout(&uc, &fp->sf_uc, ucsz); 106 mutex_enter(p->p_lock); 107 108 if (error != 0) { 109 /* 110 * Process has trashed its stack; give it an illegal 111 * instruction to halt it in its tracks. 112 */ 113 sigexit(l, SIGILL); 114 /* NOTREACHED */ 115 } 116 117 /* 118 * Set up the registers to directly invoke the signal 119 * handler. The return address will be set up to point 120 * to the signal trampoline to bounce us back. 121 */ 122 tf->f_regs[_R_A0] = sig; 123 tf->f_regs[_R_A1] = (__greg_t)&fp->sf_si; 124 tf->f_regs[_R_A2] = (__greg_t)&fp->sf_uc; 125 126 tf->f_regs[_R_PC] = (__greg_t)catcher; 127 tf->f_regs[_R_T9] = (__greg_t)catcher; 128 tf->f_regs[_R_SP] = (__greg_t)fp; 129 tf->f_regs[_R_RA] = (__greg_t)ps->sa_sigdesc[sig].sd_tramp; 130 131 /* Remember that we're now on the signal stack. */ 132 if (onstack) 133 l->l_sigstk.ss_flags |= SS_ONSTACK; 134 } 135