1 /* $NetBSD: sys_module.c,v 1.19 2015/08/24 22:50:32 pooka Exp $ */ 2 3 /*- 4 * Copyright (c) 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * System calls relating to loadable modules. 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: sys_module.c,v 1.19 2015/08/24 22:50:32 pooka Exp $"); 35 36 #ifdef _KERNEL_OPT 37 #include "opt_modular.h" 38 #endif 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/proc.h> 43 #include <sys/namei.h> 44 #include <sys/kauth.h> 45 #include <sys/kmem.h> 46 #include <sys/kobj.h> 47 #include <sys/module.h> 48 #include <sys/syscall.h> 49 #include <sys/syscallargs.h> 50 51 /* 52 * Arbitrary limit to avoid DoS for excessive memory allocation. 53 */ 54 #define MAXPROPSLEN 4096 55 56 int 57 handle_modctl_load(const char *ml_filename, int ml_flags, const char *ml_props, 58 size_t ml_propslen) 59 { 60 char *path; 61 char *props; 62 int error; 63 prop_dictionary_t dict; 64 size_t propslen = 0; 65 66 if ((ml_props != NULL && ml_propslen == 0) || 67 (ml_props == NULL && ml_propslen > 0)) { 68 return EINVAL; 69 } 70 71 path = PNBUF_GET(); 72 error = copyinstr(ml_filename, path, MAXPATHLEN, NULL); 73 if (error != 0) 74 goto out1; 75 76 if (ml_props != NULL) { 77 if (ml_propslen > MAXPROPSLEN) { 78 error = ENOMEM; 79 goto out1; 80 } 81 propslen = ml_propslen + 1; 82 83 props = kmem_alloc(propslen, KM_SLEEP); 84 if (props == NULL) { 85 error = ENOMEM; 86 goto out1; 87 } 88 89 error = copyinstr(ml_props, props, propslen, NULL); 90 if (error != 0) 91 goto out2; 92 93 dict = prop_dictionary_internalize(props); 94 if (dict == NULL) { 95 error = EINVAL; 96 goto out2; 97 } 98 } else { 99 dict = NULL; 100 props = NULL; 101 } 102 103 error = module_load(path, ml_flags, dict, MODULE_CLASS_ANY); 104 105 if (dict != NULL) { 106 prop_object_release(dict); 107 } 108 109 out2: 110 if (props != NULL) { 111 kmem_free(props, propslen); 112 } 113 out1: 114 PNBUF_PUT(path); 115 return error; 116 } 117 118 int 119 sys_modctl(struct lwp *l, const struct sys_modctl_args *uap, 120 register_t *retval) 121 { 122 /* { 123 syscallarg(int) cmd; 124 syscallarg(void *) arg; 125 } */ 126 char buf[MAXMODNAME]; 127 size_t mslen; 128 module_t *mod; 129 modinfo_t *mi; 130 modstat_t *ms, *mso; 131 vaddr_t addr; 132 size_t size; 133 struct iovec iov; 134 modctl_load_t ml; 135 int error; 136 void *arg; 137 #ifdef MODULAR 138 uintptr_t loadtype; 139 #endif 140 141 arg = SCARG(uap, arg); 142 143 switch (SCARG(uap, cmd)) { 144 case MODCTL_LOAD: 145 error = copyin(arg, &ml, sizeof(ml)); 146 if (error != 0) 147 break; 148 error = handle_modctl_load(ml.ml_filename, ml.ml_flags, 149 ml.ml_props, ml.ml_propslen); 150 break; 151 152 case MODCTL_UNLOAD: 153 error = copyinstr(arg, buf, sizeof(buf), NULL); 154 if (error == 0) { 155 error = module_unload(buf); 156 } 157 break; 158 159 case MODCTL_STAT: 160 error = copyin(arg, &iov, sizeof(iov)); 161 if (error != 0) { 162 break; 163 } 164 kernconfig_lock(); 165 mslen = (module_count+module_builtinlist+1) * sizeof(modstat_t); 166 mso = kmem_zalloc(mslen, KM_SLEEP); 167 if (mso == NULL) { 168 kernconfig_unlock(); 169 return ENOMEM; 170 } 171 ms = mso; 172 TAILQ_FOREACH(mod, &module_list, mod_chain) { 173 mi = mod->mod_info; 174 strlcpy(ms->ms_name, mi->mi_name, sizeof(ms->ms_name)); 175 if (mi->mi_required != NULL) { 176 strlcpy(ms->ms_required, mi->mi_required, 177 sizeof(ms->ms_required)); 178 } 179 if (mod->mod_kobj != NULL) { 180 kobj_stat(mod->mod_kobj, &addr, &size); 181 ms->ms_addr = addr; 182 ms->ms_size = size; 183 } 184 ms->ms_class = mi->mi_class; 185 ms->ms_refcnt = mod->mod_refcnt; 186 ms->ms_source = mod->mod_source; 187 ms++; 188 } 189 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 190 mi = mod->mod_info; 191 strlcpy(ms->ms_name, mi->mi_name, sizeof(ms->ms_name)); 192 if (mi->mi_required != NULL) { 193 strlcpy(ms->ms_required, mi->mi_required, 194 sizeof(ms->ms_required)); 195 } 196 if (mod->mod_kobj != NULL) { 197 kobj_stat(mod->mod_kobj, &addr, &size); 198 ms->ms_addr = addr; 199 ms->ms_size = size; 200 } 201 ms->ms_class = mi->mi_class; 202 ms->ms_refcnt = -1; 203 KASSERT(mod->mod_source == MODULE_SOURCE_KERNEL); 204 ms->ms_source = mod->mod_source; 205 ms++; 206 } 207 kernconfig_unlock(); 208 error = copyout(mso, iov.iov_base, 209 min(mslen - sizeof(modstat_t), iov.iov_len)); 210 kmem_free(mso, mslen); 211 if (error == 0) { 212 iov.iov_len = mslen - sizeof(modstat_t); 213 error = copyout(&iov, arg, sizeof(iov)); 214 } 215 break; 216 217 case MODCTL_EXISTS: 218 #ifndef MODULAR 219 error = ENOSYS; 220 #else 221 loadtype = (uintptr_t)arg; 222 switch (loadtype) { /* 0 = modload, 1 = autoload */ 223 case 0: /* FALLTHROUGH */ 224 case 1: 225 error = kauth_authorize_system(kauth_cred_get(), 226 KAUTH_SYSTEM_MODULE, 0, 227 (void *)(uintptr_t)MODCTL_LOAD, 228 (void *)loadtype, NULL); 229 break; 230 231 default: 232 error = EINVAL; 233 break; 234 } 235 #endif 236 break; 237 238 default: 239 error = EINVAL; 240 break; 241 } 242 243 return error; 244 } 245