1 /* $NetBSD: sys_module.c,v 1.21 2015/12/12 14:47:37 maxv 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 1.21 2015/12/12 14:47:37 maxv 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 static int 119 handle_modctl_stat(struct iovec *iov, void *arg) 120 { 121 modstat_t *ms, *mso; 122 modinfo_t *mi; 123 module_t *mod; 124 vaddr_t addr; 125 size_t size; 126 size_t mslen; 127 int error; 128 129 kernconfig_lock(); 130 mslen = (module_count+module_builtinlist+1) * sizeof(modstat_t); 131 mso = kmem_zalloc(mslen, KM_SLEEP); 132 if (mso == NULL) { 133 kernconfig_unlock(); 134 return ENOMEM; 135 } 136 ms = mso; 137 TAILQ_FOREACH(mod, &module_list, mod_chain) { 138 mi = mod->mod_info; 139 strlcpy(ms->ms_name, mi->mi_name, sizeof(ms->ms_name)); 140 if (mi->mi_required != NULL) { 141 strlcpy(ms->ms_required, mi->mi_required, 142 sizeof(ms->ms_required)); 143 } 144 if (mod->mod_kobj != NULL) { 145 kobj_stat(mod->mod_kobj, &addr, &size); 146 ms->ms_addr = addr; 147 ms->ms_size = size; 148 } 149 ms->ms_class = mi->mi_class; 150 ms->ms_refcnt = mod->mod_refcnt; 151 ms->ms_source = mod->mod_source; 152 ms->ms_flags = mod->mod_flags; 153 ms++; 154 } 155 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 156 mi = mod->mod_info; 157 strlcpy(ms->ms_name, mi->mi_name, sizeof(ms->ms_name)); 158 if (mi->mi_required != NULL) { 159 strlcpy(ms->ms_required, mi->mi_required, 160 sizeof(ms->ms_required)); 161 } 162 if (mod->mod_kobj != NULL) { 163 kobj_stat(mod->mod_kobj, &addr, &size); 164 ms->ms_addr = addr; 165 ms->ms_size = size; 166 } 167 ms->ms_class = mi->mi_class; 168 ms->ms_refcnt = -1; 169 KASSERT(mod->mod_source == MODULE_SOURCE_KERNEL); 170 ms->ms_source = mod->mod_source; 171 ms++; 172 } 173 kernconfig_unlock(); 174 error = copyout(mso, iov->iov_base, 175 min(mslen - sizeof(modstat_t), iov->iov_len)); 176 kmem_free(mso, mslen); 177 if (error == 0) { 178 iov->iov_len = mslen - sizeof(modstat_t); 179 error = copyout(iov, arg, sizeof(*iov)); 180 } 181 182 return error; 183 } 184 185 int 186 sys_modctl(struct lwp *l, const struct sys_modctl_args *uap, 187 register_t *retval) 188 { 189 /* { 190 syscallarg(int) cmd; 191 syscallarg(void *) arg; 192 } */ 193 char buf[MAXMODNAME]; 194 struct iovec iov; 195 modctl_load_t ml; 196 int error; 197 void *arg; 198 #ifdef MODULAR 199 uintptr_t loadtype; 200 #endif 201 202 arg = SCARG(uap, arg); 203 204 switch (SCARG(uap, cmd)) { 205 case MODCTL_LOAD: 206 error = copyin(arg, &ml, sizeof(ml)); 207 if (error != 0) 208 break; 209 error = handle_modctl_load(ml.ml_filename, ml.ml_flags, 210 ml.ml_props, ml.ml_propslen); 211 break; 212 213 case MODCTL_UNLOAD: 214 error = copyinstr(arg, buf, sizeof(buf), NULL); 215 if (error == 0) { 216 error = module_unload(buf); 217 } 218 break; 219 220 case MODCTL_STAT: 221 error = copyin(arg, &iov, sizeof(iov)); 222 if (error != 0) { 223 break; 224 } 225 error = handle_modctl_stat(&iov, arg); 226 break; 227 228 case MODCTL_EXISTS: 229 #ifndef MODULAR 230 error = ENOSYS; 231 #else 232 loadtype = (uintptr_t)arg; 233 switch (loadtype) { /* 0 = modload, 1 = autoload */ 234 case 0: /* FALLTHROUGH */ 235 case 1: 236 error = kauth_authorize_system(kauth_cred_get(), 237 KAUTH_SYSTEM_MODULE, 0, 238 (void *)(uintptr_t)MODCTL_LOAD, 239 (void *)loadtype, NULL); 240 break; 241 242 default: 243 error = EINVAL; 244 break; 245 } 246 #endif 247 break; 248 249 default: 250 error = EINVAL; 251 break; 252 } 253 254 return error; 255 } 256