1 /*        $NetBSD: netbsd32_module.c,v 1.11 2022/05/24 06:20:04 andvar Exp $    */
2 
3 /*-
4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software developed for The NetBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
22  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: netbsd32_module.c,v 1.11 2022/05/24 06:20:04 andvar Exp $");
33 
34 #include <sys/param.h>
35 #include <sys/dirent.h>
36 #include <sys/kauth.h>
37 #include <sys/module.h>
38 #include <sys/kobj.h>
39 
40 #include <compat/netbsd32/netbsd32.h>
41 #include <compat/netbsd32/netbsd32_syscall.h>
42 #include <compat/netbsd32/netbsd32_syscallargs.h>
43 #include <compat/netbsd32/netbsd32_conv.h>
44 
45 static int
modctl32_handle_stat(struct netbsd32_iovec * iov,void * arg)46 modctl32_handle_stat(struct netbsd32_iovec *iov, void *arg)
47 {
48           int ms_cnt;
49           modstat_t *ms, *mso;
50           size_t ms_len;
51           char *req, *reqo;
52           size_t req_len;
53           char *out_p;
54           size_t out_s;
55 
56           modinfo_t *mi;
57           module_t *mod;
58           vaddr_t addr;
59           size_t size;
60           size_t used;
61           int off;
62           int error;
63           bool stataddr;
64 
65           /* If not privileged, don't expose kernel addresses. */
66           error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE,
67               0, (void *)(uintptr_t)MODCTL_STAT, NULL, NULL);
68           stataddr = (error == 0);
69 
70           kernconfig_lock();
71           ms_cnt = 0;
72           req_len = 1;
73 
74           /*
75            * Count up the number of modstat_t needed, and total size of
76            * require_module lists on both active and built-in lists
77            */
78           TAILQ_FOREACH(mod, &module_list, mod_chain) {
79                     ms_cnt++;
80                     mi = mod->mod_info;
81                     if (mi->mi_required != NULL) {
82                               req_len += strlen(mi->mi_required) + 1;
83                     }
84           }
85           TAILQ_FOREACH(mod, &module_builtins, mod_chain) {
86                     ms_cnt++;
87                     mi = mod->mod_info;
88                     if (mi->mi_required != NULL) {
89                               req_len += strlen(mi->mi_required) + 1;
90                     }
91           }
92 
93           /* Allocate internal buffers to hold all the output data */
94           ms_len = ms_cnt * sizeof(modstat_t);
95           ms = kmem_zalloc(ms_len, KM_SLEEP);
96           req = kmem_zalloc(req_len, KM_SLEEP);
97 
98           mso = ms;
99           reqo = req++;
100           off = 1;
101 
102           /*
103            * Load data into our internal buffers for both active and
104            * built-in module lists
105            */
106           TAILQ_FOREACH(mod, &module_list, mod_chain) {
107                     mi = mod->mod_info;
108                     strlcpy(ms->ms_name, mi->mi_name, sizeof(ms->ms_name));
109                     if (mi->mi_required != NULL) {
110                               ms->ms_reqoffset = off;
111                               used = strlcpy(req,  mi->mi_required, req_len - off);
112                               KASSERTMSG(used < req_len - off, "reqlist grew!");
113                               off = used + 1;
114                               req += used + 1;
115                     } else
116                               ms->ms_reqoffset = 0;
117                     if (mod->mod_kobj != NULL && stataddr) {
118                               kobj_stat(mod->mod_kobj, &addr, &size);
119                               ms->ms_addr = addr;
120                               ms->ms_size = size;
121                     }
122                     ms->ms_class = mi->mi_class;
123                     ms->ms_refcnt = mod->mod_refcnt;
124                     ms->ms_source = mod->mod_source;
125                     ms->ms_flags = mod->mod_flags;
126                     ms++;
127           }
128           TAILQ_FOREACH(mod, &module_builtins, mod_chain) {
129                     mi = mod->mod_info;
130                     strlcpy(ms->ms_name, mi->mi_name, sizeof(ms->ms_name));
131                     if (mi->mi_required != NULL) {
132                               ms->ms_reqoffset = off;
133                               used = strlcpy(req,  mi->mi_required, req_len - off);
134                               KASSERTMSG(used < req_len - off, "reqlist grew!");
135                               off += used + 1;
136                               req += used + 1;
137                     } else
138                               ms->ms_reqoffset = 0;
139                     if (mod->mod_kobj != NULL && stataddr) {
140                               kobj_stat(mod->mod_kobj, &addr, &size);
141                               ms->ms_addr = addr;
142                               ms->ms_size = size;
143                     }
144                     ms->ms_class = mi->mi_class;
145                     ms->ms_refcnt = -1;
146                     KASSERT(mod->mod_source == MODULE_SOURCE_KERNEL);
147                     ms->ms_source = mod->mod_source;
148                     ms++;
149           }
150           kernconfig_unlock();
151 
152           /*
153            * Now copyout our internal buffers back to userland
154            */
155           out_p = NETBSD32PTR64(iov->iov_base);
156           out_s = iov->iov_len;
157           size = sizeof(ms_cnt);
158 
159           /* Copy out the count of modstat_t */
160           if (out_s) {
161                     size = uimin(sizeof(ms_cnt), out_s);
162                     error = copyout(&ms_cnt, out_p, size);
163                     out_p += size;
164                     out_s -= size;
165           }
166           /* Copy out the modstat_t array */
167           if (out_s && error == 0) {
168                     size = uimin(ms_len, out_s);
169                     error = copyout(mso, out_p, size);
170                     out_p += size;
171                     out_s -= size;
172           }
173           /* Copy out the "required" strings */
174           if (out_s && error == 0) {
175                     size = uimin(req_len, out_s);
176                     error = copyout(reqo, out_p, size);
177                     out_p += size;
178                     out_s -= size;
179           }
180           kmem_free(mso, ms_len);
181           kmem_free(reqo, req_len);
182 
183           /* Finally, update the userland copy of the iovec's length */
184           if (error == 0) {
185                     iov->iov_len = ms_len + req_len + sizeof(ms_cnt);
186                     error = copyout(iov, arg, sizeof(*iov));
187           }
188 
189           return error;
190 }
191 
192 int
compat32_80_modctl_compat_stub(struct lwp * lwp,const struct netbsd32_modctl_args * uap,register_t * result)193 compat32_80_modctl_compat_stub(struct lwp *lwp,
194     const struct netbsd32_modctl_args *uap, register_t *result)
195 {
196 
197           return EPASSTHROUGH;
198 }
199 
200 int
netbsd32_modctl(struct lwp * lwp,const struct netbsd32_modctl_args * uap,register_t * result)201 netbsd32_modctl(struct lwp *lwp, const struct netbsd32_modctl_args *uap,
202           register_t *result)
203 {
204           /* {
205                     syscallarg(int) cmd;
206                     syscallarg(netbsd32_voidp) arg;
207           } */
208           char buf[MAXMODNAME];
209           struct netbsd32_iovec iov;
210           struct netbsd32_modctl_load ml;
211           int error;
212           void *arg;
213 #ifdef MODULAR
214           uintptr_t loadtype;
215 #endif
216 
217           arg = SCARG_P32(uap, arg);
218 
219           MODULE_HOOK_CALL(compat32_80_modctl_hook, (lwp, uap, result),
220               enosys(), error);
221           if (error != EPASSTHROUGH && error != ENOSYS)
222                     return error;
223 
224           switch (SCARG(uap, cmd)) {
225           case MODCTL_LOAD:
226                     error = copyin(arg, &ml, sizeof(ml));
227                     if (error != 0)
228                               break;
229                     error = handle_modctl_load(NETBSD32PTR64(ml.ml_filename),
230                          ml.ml_flags, NETBSD32PTR64(ml.ml_props), ml.ml_propslen);
231                     break;
232 
233           case MODCTL_UNLOAD:
234                     error = copyinstr(arg, buf, sizeof(buf), NULL);
235                     if (error == 0) {
236                               error = module_unload(buf);
237                     }
238                     break;
239 
240           case MODCTL_STAT:
241                     error = copyin(arg, &iov, sizeof(iov));
242                     if (error != 0) {
243                               break;
244                     }
245                     error = modctl32_handle_stat(&iov, arg);
246                     break;
247 
248           case MODCTL_EXISTS:
249 #ifndef MODULAR
250                     error = ENOSYS;
251 #else
252                     loadtype = (uintptr_t)arg;
253                     switch (loadtype) { /* 0 = modload, 1 = autoload */
254                     case 0:                       /* FALLTHROUGH */
255                     case 1:
256                               error = kauth_authorize_system(kauth_cred_get(),
257                                    KAUTH_SYSTEM_MODULE, 0,
258                                    (void *)(uintptr_t)MODCTL_LOAD,
259                                    (void *)loadtype, NULL);
260                               break;
261 
262                     default:
263                               error = EINVAL;
264                               break;
265                     }
266 #endif
267                     break;
268 
269           default:
270                     error = EINVAL;
271                     break;
272           }
273 
274           return error;
275 }
276