1 /* $NetBSD: kern_sig_16.c,v 1.10 2024/12/10 10:52:05 mlelstv Exp $ */ 2 3 /*- 4 * Copyright (c) 2006, 2007, 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Andrew Doran. 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 /* 33 * Copyright (c) 1982, 1986, 1989, 1991, 1993 34 * The Regents of the University of California. All rights reserved. 35 * (c) UNIX System Laboratories, Inc. 36 * All or some portions of this file are derived from material licensed 37 * to the University of California by American Telephone and Telegraph 38 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 39 * the permission of UNIX System Laboratories, Inc. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)kern_sig.c 8.14 (Berkeley) 5/14/95 66 */ 67 68 #include <sys/cdefs.h> 69 __KERNEL_RCSID(0, "$NetBSD: kern_sig_16.c,v 1.10 2024/12/10 10:52:05 mlelstv Exp $"); 70 71 #if defined(_KERNEL_OPT) 72 #include "opt_compat_netbsd.h" 73 #endif 74 75 #include <sys/param.h> 76 #include <sys/exec.h> 77 #include <sys/kernel.h> 78 #include <sys/rwlock.h> 79 #include <sys/signalvar.h> 80 #include <sys/proc.h> 81 #include <sys/pool.h> 82 #include <sys/syscall.h> 83 #include <sys/syscallvar.h> 84 #include <sys/syscallargs.h> 85 #include <sys/kauth.h> 86 #include <sys/wait.h> 87 #include <sys/kmem.h> 88 #include <sys/compat_stub.h> 89 90 #include <uvm/uvm_object.h> 91 #include <uvm/uvm_prot.h> 92 #include <uvm/uvm_pager.h> 93 94 #include <compat/common/compat_mod.h> 95 96 #ifdef COMPAT_NETBSD32 97 # ifndef __aarch64__ 98 # define COMPAT_SIGCONTEXT 99 # endif 100 #else /* COMPAT_NETBSD32 */ 101 # if !defined(__amd64__) && !defined(__aarch64__) 102 # define COMPAT_SIGCONTEXT 103 # endif 104 #endif /* COMPAT_NETBSD32 */ 105 106 #ifdef COMPAT_SIGCONTEXT 107 extern char sigcode[], esigcode[]; 108 struct uvm_object *emul_netbsd_object; 109 #endif 110 111 static const struct syscall_package kern_sig_16_syscalls[] = { 112 #ifdef COMPAT_SIGCONTEXT 113 { SYS_compat_16___sigaction14, 0, 114 (sy_call_t *)compat_16_sys___sigaction14 }, 115 /* compat_16_sigreturn14 is in MD code! */ 116 { SYS_compat_16___sigreturn14, 0, 117 (sy_call_t *)compat_16_sys___sigreturn14 }, 118 #endif 119 { 0, 0, NULL } 120 }; 121 122 int 123 compat_16_sys___sigaction14(struct lwp *l, 124 const struct compat_16_sys___sigaction14_args *uap, register_t *retval) 125 { 126 /* { 127 syscallarg(int) signum; 128 syscallarg(const struct sigaction *) nsa; 129 syscallarg(struct sigaction *) osa; 130 } */ 131 struct sigaction nsa, osa; 132 int error; 133 134 if (SCARG(uap, nsa)) { 135 error = copyin(SCARG(uap, nsa), &nsa, sizeof(nsa)); 136 if (error) 137 return (error); 138 } 139 error = sigaction1(l, SCARG(uap, signum), 140 SCARG(uap, nsa) ? &nsa : 0, SCARG(uap, osa) ? &osa : 0, 141 NULL, 0); 142 if (error) 143 return (error); 144 if (SCARG(uap, osa)) { 145 error = copyout(&osa, SCARG(uap, osa), sizeof(osa)); 146 if (error) 147 return (error); 148 } 149 return (0); 150 } 151 152 int 153 kern_sig_16_init(void) 154 { 155 int error; 156 157 error = syscall_establish(NULL, kern_sig_16_syscalls); 158 if (error) 159 return error; 160 #if defined(COMPAT_SIGCONTEXT) 161 KASSERT(emul_netbsd.e_sigobject == NULL); 162 rw_enter(&exec_lock, RW_WRITER); 163 emul_netbsd.e_sigcode = sigcode; 164 emul_netbsd.e_esigcode = esigcode; 165 emul_netbsd.e_sigobject = &emul_netbsd_object; 166 error = exec_sigcode_alloc(&emul_netbsd); 167 if (error) { 168 emul_netbsd.e_sigcode = NULL; 169 emul_netbsd.e_esigcode = NULL; 170 emul_netbsd.e_sigobject = NULL; 171 } 172 rw_exit(&exec_lock); 173 if (error) 174 return error; 175 MODULE_HOOK_SET(sendsig_sigcontext_16_hook, sendsig_sigcontext); 176 #endif 177 178 return 0; 179 } 180 181 int 182 kern_sig_16_fini(void) 183 { 184 proc_t *p; 185 int error; 186 187 error = syscall_disestablish(NULL, kern_sig_16_syscalls); 188 if (error) 189 return error; 190 /* 191 * Ensure sendsig_sigcontext() is not being used. 192 * module_lock prevents the flag being set on any 193 * further processes while we are here. See 194 * sigaction1() for the opposing half. 195 */ 196 mutex_enter(&proc_lock); 197 PROCLIST_FOREACH(p, &allproc) { 198 if ((p->p_lflag & PL_SIGCOMPAT) != 0) { 199 break; 200 } 201 } 202 mutex_exit(&proc_lock); 203 if (p != NULL) { 204 syscall_establish(NULL, kern_sig_16_syscalls); 205 return EBUSY; 206 } 207 208 #if defined(COMPAT_SIGCONTEXT) 209 /* 210 * The sigobject may persist if still in use, but 211 * is reference counted so will die eventually. 212 */ 213 rw_enter(&exec_lock, RW_WRITER); 214 exec_sigcode_free(&emul_netbsd); 215 emul_netbsd_object = NULL; 216 emul_netbsd.e_sigcode = NULL; 217 emul_netbsd.e_esigcode = NULL; 218 emul_netbsd.e_sigobject = NULL; 219 rw_exit(&exec_lock); 220 221 MODULE_HOOK_UNSET(sendsig_sigcontext_16_hook); 222 #endif 223 return 0; 224 } 225 226