netbsd32_module.c revision 1.10
1/*	$NetBSD: netbsd32_module.c,v 1.10 2019/03/01 11:06:56 pgoyette 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 1.10 2019/03/01 11:06:56 pgoyette 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
45static int
46modctl32_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	 * build-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
192int
193compat32_80_modctl_compat_stub(struct lwp *lwp,
194    const struct netbsd32_modctl_args *uap, register_t *result)
195{
196
197	return EPASSTHROUGH;
198}
199
200int
201netbsd32_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