| 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 | |