1 /* $NetBSD: sys_module.c,v 1.17 2014/07/10 21:13:52 christos 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 1.17 2014/07/10 21:13:52 christos Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/proc.h> 39 #include <sys/namei.h> 40 #include <sys/kauth.h> 41 #include <sys/kmem.h> 42 #include <sys/kobj.h> 43 #include <sys/module.h> 44 #include <sys/syscall.h> 45 #include <sys/syscallargs.h> 46 47 #include <opt_modular.h> 48 49 /* 50 * Arbitrary limit to avoid DoS for excessive memory allocation. 51 */ 52 #define MAXPROPSLEN 4096 53 54 static int 55 handle_modctl_load(modctl_load_t *ml) 56 { 57 char *path; 58 char *props; 59 int error; 60 prop_dictionary_t dict; 61 size_t propslen = 0; 62 63 if ((ml->ml_props != NULL && ml->ml_propslen == 0) || 64 (ml->ml_props == NULL && ml->ml_propslen > 0)) { 65 return EINVAL; 66 } 67 68 path = PNBUF_GET(); 69 error = copyinstr(ml->ml_filename, path, MAXPATHLEN, NULL); 70 if (error != 0) 71 goto out1; 72 73 if (ml->ml_props != NULL) { 74 if (ml->ml_propslen > MAXPROPSLEN) { 75 error = ENOMEM; 76 goto out1; 77 } 78 propslen = ml->ml_propslen + 1; 79 80 props = kmem_alloc(propslen, KM_SLEEP); 81 if (props == NULL) { 82 error = ENOMEM; 83 goto out1; 84 } 85 86 error = copyinstr(ml->ml_props, props, propslen, NULL); 87 if (error != 0) 88 goto out2; 89 90 dict = prop_dictionary_internalize(props); 91 if (dict == NULL) { 92 error = EINVAL; 93 goto out2; 94 } 95 } else { 96 dict = NULL; 97 props = NULL; 98 } 99 100 error = module_load(path, ml->ml_flags, dict, MODULE_CLASS_ANY); 101 102 if (dict != NULL) { 103 prop_object_release(dict); 104 } 105 106 out2: 107 if (props != NULL) { 108 kmem_free(props, propslen); 109 } 110 out1: 111 PNBUF_PUT(path); 112 return error; 113 } 114 115 int 116 sys_modctl(struct lwp *l, const struct sys_modctl_args *uap, 117 register_t *retval) 118 { 119 /* { 120 syscallarg(int) cmd; 121 syscallarg(void *) arg; 122 } */ 123 char buf[MAXMODNAME]; 124 size_t mslen; 125 module_t *mod; 126 modinfo_t *mi; 127 modstat_t *ms, *mso; 128 vaddr_t addr; 129 size_t size; 130 struct iovec iov; 131 modctl_load_t ml; 132 int error; 133 void *arg; 134 #ifdef MODULAR 135 uintptr_t loadtype; 136 #endif 137 138 arg = SCARG(uap, arg); 139 140 switch (SCARG(uap, cmd)) { 141 case MODCTL_LOAD: 142 error = copyin(arg, &ml, sizeof(ml)); 143 if (error != 0) 144 break; 145 error = handle_modctl_load(&ml); 146 break; 147 148 case MODCTL_UNLOAD: 149 error = copyinstr(arg, buf, sizeof(buf), NULL); 150 if (error == 0) { 151 error = module_unload(buf); 152 } 153 break; 154 155 case MODCTL_STAT: 156 error = copyin(arg, &iov, sizeof(iov)); 157 if (error != 0) { 158 break; 159 } 160 kernconfig_lock(); 161 mslen = (module_count+module_builtinlist+1) * sizeof(modstat_t); 162 mso = kmem_zalloc(mslen, KM_SLEEP); 163 if (mso == NULL) { 164 kernconfig_unlock(); 165 return ENOMEM; 166 } 167 ms = mso; 168 TAILQ_FOREACH(mod, &module_list, mod_chain) { 169 mi = mod->mod_info; 170 strlcpy(ms->ms_name, mi->mi_name, sizeof(ms->ms_name)); 171 if (mi->mi_required != NULL) { 172 strlcpy(ms->ms_required, mi->mi_required, 173 sizeof(ms->ms_required)); 174 } 175 if (mod->mod_kobj != NULL) { 176 kobj_stat(mod->mod_kobj, &addr, &size); 177 ms->ms_addr = addr; 178 ms->ms_size = size; 179 } 180 ms->ms_class = mi->mi_class; 181 ms->ms_refcnt = mod->mod_refcnt; 182 ms->ms_source = mod->mod_source; 183 ms++; 184 } 185 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 186 mi = mod->mod_info; 187 strlcpy(ms->ms_name, mi->mi_name, sizeof(ms->ms_name)); 188 if (mi->mi_required != NULL) { 189 strlcpy(ms->ms_required, mi->mi_required, 190 sizeof(ms->ms_required)); 191 } 192 if (mod->mod_kobj != NULL) { 193 kobj_stat(mod->mod_kobj, &addr, &size); 194 ms->ms_addr = addr; 195 ms->ms_size = size; 196 } 197 ms->ms_class = mi->mi_class; 198 ms->ms_refcnt = -1; 199 KASSERT(mod->mod_source == MODULE_SOURCE_KERNEL); 200 ms->ms_source = mod->mod_source; 201 ms++; 202 } 203 kernconfig_unlock(); 204 error = copyout(mso, iov.iov_base, 205 min(mslen - sizeof(modstat_t), iov.iov_len)); 206 kmem_free(mso, mslen); 207 if (error == 0) { 208 iov.iov_len = mslen - sizeof(modstat_t); 209 error = copyout(&iov, arg, sizeof(iov)); 210 } 211 break; 212 213 case MODCTL_EXISTS: 214 #ifndef MODULAR 215 error = ENOSYS; 216 #else 217 loadtype = (uintptr_t)arg; 218 switch (loadtype) { /* 0 = modload, 1 = autoload */ 219 case 0: /* FALLTHROUGH */ 220 case 1: 221 error = kauth_authorize_system(kauth_cred_get(), 222 KAUTH_SYSTEM_MODULE, 0, 223 (void *)(uintptr_t)MODCTL_LOAD, 224 (void *)loadtype, NULL); 225 break; 226 227 default: 228 error = EINVAL; 229 break; 230 } 231 #endif 232 break; 233 234 default: 235 error = EINVAL; 236 break; 237 } 238 239 return error; 240 } 241