1 /* $NetBSD: netbsd32_execve.c,v 1.44 2021/11/11 17:32:46 martin Exp $ */
2
3 /*
4 * Copyright (c) 1998, 2001 Matthew R. Green
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 AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30
31 __KERNEL_RCSID(0, "$NetBSD: netbsd32_execve.c,v 1.44 2021/11/11 17:32:46 martin Exp $");
32
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/atomic.h>
36 #include <sys/mount.h>
37 #include <sys/namei.h>
38 #include <sys/stat.h>
39 #include <sys/spawn.h>
40 #include <sys/uidinfo.h>
41 #include <sys/vnode.h>
42 #include <sys/file.h>
43 #include <sys/filedesc.h>
44 #include <sys/syscallargs.h>
45 #include <sys/proc.h>
46 #include <sys/exec.h>
47
48 #include <compat/netbsd32/netbsd32.h>
49 #include <compat/netbsd32/netbsd32_syscall.h>
50 #include <compat/netbsd32/netbsd32_syscallargs.h>
51
52 static int
netbsd32_execve_fetch_element(char * const * array,size_t index,char ** value)53 netbsd32_execve_fetch_element(char * const *array, size_t index, char **value)
54 {
55 int error;
56 netbsd32_charp const *a32 = (void const *)array;
57 netbsd32_charp e;
58
59 error = copyin(a32 + index, &e, sizeof(e));
60 if (error)
61 return error;
62 *value = (char *)NETBSD32PTR64(e);
63 return 0;
64 }
65
66 int
netbsd32_execve(struct lwp * l,const struct netbsd32_execve_args * uap,register_t * retval)67 netbsd32_execve(struct lwp *l, const struct netbsd32_execve_args *uap, register_t *retval)
68 {
69 /* {
70 syscallarg(const netbsd32_charp) path;
71 syscallarg(netbsd32_charpp) argp;
72 syscallarg(netbsd32_charpp) envp;
73 } */
74
75 return execve1(l, true, SCARG_P32(uap, path), -1, SCARG_P32(uap, argp),
76 SCARG_P32(uap, envp), netbsd32_execve_fetch_element);
77 }
78
79 int
netbsd32_fexecve(struct lwp * l,const struct netbsd32_fexecve_args * uap,register_t * retval)80 netbsd32_fexecve(struct lwp *l, const struct netbsd32_fexecve_args *uap,
81 register_t *retval)
82 {
83 /* {
84 syscallarg(int) fd;
85 syscallarg(netbsd32_charpp) argp;
86 syscallarg(netbsd32_charpp) envp;
87 } */
88
89 return execve1(l, false, NULL, SCARG(uap, fd), SCARG_P32(uap, argp),
90 SCARG_P32(uap, envp), netbsd32_execve_fetch_element);
91 }
92
93 static __inline bool
netbsd32_posix_spawn_fae_path(struct posix_spawn_file_actions_entry * fae,struct netbsd32_posix_spawn_file_actions_entry * fae32,char *** pathp,char ** pathp32)94 netbsd32_posix_spawn_fae_path(
95 struct posix_spawn_file_actions_entry *fae,
96 struct netbsd32_posix_spawn_file_actions_entry *fae32,
97 char ***pathp, char **pathp32)
98 {
99 switch (fae->fae_action) {
100 case FAE_OPEN:
101 *pathp = &fae->fae_path;
102 *pathp32 = NETBSD32PTR64(fae32->fae_data.open.path);
103 return true;
104 case FAE_CHDIR:
105 *pathp = &fae->fae_chdir_path;
106 *pathp32 = NETBSD32PTR64(fae32->fae_data.chdir.path);
107 return true;
108 default:
109 return false;
110 }
111 }
112
113 static int
netbsd32_posix_spawn_fa_alloc(struct posix_spawn_file_actions ** fap,const struct netbsd32_posix_spawn_file_actions * ufa,rlim_t lim)114 netbsd32_posix_spawn_fa_alloc(struct posix_spawn_file_actions **fap,
115 const struct netbsd32_posix_spawn_file_actions *ufa, rlim_t lim)
116 {
117 struct posix_spawn_file_actions *fa;
118 struct netbsd32_posix_spawn_file_actions fa32;
119 struct netbsd32_posix_spawn_file_actions_entry *fae32 = NULL, *f32 = NULL;
120 struct posix_spawn_file_actions_entry *fae;
121 char *pbuf = NULL, **pathp = NULL, *pathp32 = NULL;
122 int error;
123 size_t fal, fal32, slen, i = 0;
124
125 error = copyin(ufa, &fa32, sizeof(fa32));
126 if (error)
127 return error;
128
129 if (fa32.len == 0)
130 return 0;
131
132 fa = kmem_alloc(sizeof(*fa), KM_SLEEP);
133 fa->len = fa->size = fa32.len;
134
135 if (fa->len > lim) {
136 kmem_free(fa, sizeof(*fa));
137 return EINVAL;
138 }
139
140 fal = fa->len * sizeof(*fae);
141 fal32 = fa->len * sizeof(*fae32);
142
143 fa->fae = kmem_alloc(fal, KM_SLEEP);
144 fae32 = kmem_alloc(fal32, KM_SLEEP);
145 error = copyin(NETBSD32PTR64(fa32.fae), fae32, fal32);
146 if (error)
147 goto out;
148
149 pbuf = PNBUF_GET();
150 for (; i < fa->len; i++) {
151 fae = &fa->fae[i];
152 f32 = &fae32[i];
153 fae->fae_action = (unsigned)f32->fae_action;
154 fae->fae_fildes = f32->fae_fildes;
155 if (fae->fae_action == FAE_DUP2)
156 fae->fae_data.dup2.newfildes =
157 f32->fae_data.dup2.newfildes;
158 if (!netbsd32_posix_spawn_fae_path(fae, f32, &pathp, &pathp32)
159 || pathp == NULL || pathp32 == NULL)
160 continue;
161 error = copyinstr(pathp32, pbuf, MAXPATHLEN, &slen);
162 if (error)
163 goto out;
164 *pathp = kmem_alloc(slen, KM_SLEEP);
165 memcpy(*pathp, pbuf, slen);
166 fae->fae_oflag = f32->fae_oflag;
167 fae->fae_mode = f32->fae_mode;
168 }
169 PNBUF_PUT(pbuf);
170 kmem_free(fae32, fal32);
171 *fap = fa;
172 return 0;
173
174 out:
175 kmem_free(fae32, fal32);
176 if (pbuf)
177 PNBUF_PUT(pbuf);
178 posix_spawn_fa_free(fa, i);
179 return error;
180 }
181
182 int
netbsd32_posix_spawn(struct lwp * l,const struct netbsd32_posix_spawn_args * uap,register_t * retval)183 netbsd32_posix_spawn(struct lwp *l,
184 const struct netbsd32_posix_spawn_args *uap, register_t *retval)
185 {
186 /* {
187 syscallarg(netbsd32_pid_tp) pid;
188 syscallarg(const netbsd32_charp) path;
189 syscallarg(const netbsd32_posix_spawn_file_actionsp) file_actions;
190 syscallarg(const netbsd32_posix_spawnattrp) attrp;
191 syscallarg(netbsd32_charpp) argv;
192 syscallarg(netbsd32_charpp) envp;
193 } */
194
195 int error;
196 struct posix_spawn_file_actions *fa = NULL;
197 struct posix_spawnattr *sa = NULL;
198 pid_t pid;
199 bool child_ok = false;
200 rlim_t max_fileactions;
201 proc_t *p = l->l_proc;
202
203 /* check_posix_spawn() increments nprocs for us. */
204 error = check_posix_spawn(l);
205 if (error) {
206 *retval = error;
207 return 0;
208 }
209
210 /* copy in file_actions struct */
211 if (SCARG_P32(uap, file_actions) != NULL) {
212 max_fileactions = 2 * uimin(p->p_rlimit[RLIMIT_NOFILE].rlim_cur,
213 maxfiles);
214 error = netbsd32_posix_spawn_fa_alloc(&fa,
215 SCARG_P32(uap, file_actions), max_fileactions);
216 if (error)
217 goto error_exit;
218 }
219
220 /* copyin posix_spawnattr struct */
221 if (SCARG_P32(uap, attrp) != NULL) {
222 sa = kmem_alloc(sizeof(*sa), KM_SLEEP);
223 error = copyin(SCARG_P32(uap, attrp), sa, sizeof(*sa));
224 if (error)
225 goto error_exit;
226 }
227
228 /*
229 * Do the spawn
230 */
231 error = do_posix_spawn(l, &pid, &child_ok, SCARG_P32(uap, path), fa,
232 sa, SCARG_P32(uap, argv), SCARG_P32(uap, envp),
233 netbsd32_execve_fetch_element);
234 if (error)
235 goto error_exit;
236
237 if (error == 0 && SCARG_P32(uap, pid) != NULL)
238 error = copyout(&pid, SCARG_P32(uap, pid), sizeof(pid));
239
240 *retval = error;
241 return 0;
242
243 error_exit:
244 if (!child_ok) {
245 (void)chgproccnt(kauth_cred_getuid(l->l_cred), -1);
246 atomic_dec_uint(&nprocs);
247
248 if (sa)
249 kmem_free(sa, sizeof(*sa));
250 if (fa)
251 posix_spawn_fa_free(fa, fa->len);
252 }
253
254 *retval = error;
255 return 0;
256 }
257