kern_core.c revision 1.3.2.2 1 1.3.2.2 yamt /* $NetBSD: kern_core.c,v 1.3.2.2 2007/02/26 09:11:05 yamt Exp $ */
2 1.3.2.2 yamt
3 1.3.2.2 yamt /*
4 1.3.2.2 yamt * Copyright (c) 1982, 1986, 1989, 1991, 1993
5 1.3.2.2 yamt * The Regents of the University of California. All rights reserved.
6 1.3.2.2 yamt * (c) UNIX System Laboratories, Inc.
7 1.3.2.2 yamt * All or some portions of this file are derived from material licensed
8 1.3.2.2 yamt * to the University of California by American Telephone and Telegraph
9 1.3.2.2 yamt * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 1.3.2.2 yamt * the permission of UNIX System Laboratories, Inc.
11 1.3.2.2 yamt *
12 1.3.2.2 yamt * Redistribution and use in source and binary forms, with or without
13 1.3.2.2 yamt * modification, are permitted provided that the following conditions
14 1.3.2.2 yamt * are met:
15 1.3.2.2 yamt * 1. Redistributions of source code must retain the above copyright
16 1.3.2.2 yamt * notice, this list of conditions and the following disclaimer.
17 1.3.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright
18 1.3.2.2 yamt * notice, this list of conditions and the following disclaimer in the
19 1.3.2.2 yamt * documentation and/or other materials provided with the distribution.
20 1.3.2.2 yamt * 3. Neither the name of the University nor the names of its contributors
21 1.3.2.2 yamt * may be used to endorse or promote products derived from this software
22 1.3.2.2 yamt * without specific prior written permission.
23 1.3.2.2 yamt *
24 1.3.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 1.3.2.2 yamt * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 1.3.2.2 yamt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 1.3.2.2 yamt * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 1.3.2.2 yamt * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 1.3.2.2 yamt * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 1.3.2.2 yamt * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 1.3.2.2 yamt * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 1.3.2.2 yamt * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 1.3.2.2 yamt * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 1.3.2.2 yamt * SUCH DAMAGE.
35 1.3.2.2 yamt *
36 1.3.2.2 yamt * @(#)kern_sig.c 8.14 (Berkeley) 5/14/95
37 1.3.2.2 yamt */
38 1.3.2.2 yamt
39 1.3.2.2 yamt #include <sys/cdefs.h>
40 1.3.2.2 yamt __KERNEL_RCSID(0, "$NetBSD: kern_core.c,v 1.3.2.2 2007/02/26 09:11:05 yamt Exp $");
41 1.3.2.2 yamt
42 1.3.2.2 yamt #include "opt_coredump.h"
43 1.3.2.2 yamt
44 1.3.2.2 yamt #include <sys/param.h>
45 1.3.2.2 yamt #include <sys/vnode.h>
46 1.3.2.2 yamt #include <sys/namei.h>
47 1.3.2.2 yamt #include <sys/acct.h>
48 1.3.2.2 yamt #include <sys/file.h>
49 1.3.2.2 yamt #include <sys/stat.h>
50 1.3.2.2 yamt #include <sys/proc.h>
51 1.3.2.2 yamt #include <sys/exec.h>
52 1.3.2.2 yamt #include <sys/filedesc.h>
53 1.3.2.2 yamt #include <sys/kauth.h>
54 1.3.2.2 yamt
55 1.3.2.2 yamt #if !defined(COREDUMP)
56 1.3.2.2 yamt
57 1.3.2.2 yamt int
58 1.3.2.2 yamt coredump(struct lwp *l, const char *pattern)
59 1.3.2.2 yamt {
60 1.3.2.2 yamt
61 1.3.2.2 yamt return (ENOSYS);
62 1.3.2.2 yamt }
63 1.3.2.2 yamt
64 1.3.2.2 yamt #else /* COREDUMP */
65 1.3.2.2 yamt
66 1.3.2.2 yamt struct coredump_iostate {
67 1.3.2.2 yamt struct lwp *io_lwp;
68 1.3.2.2 yamt struct vnode *io_vp;
69 1.3.2.2 yamt kauth_cred_t io_cred;
70 1.3.2.2 yamt off_t io_offset;
71 1.3.2.2 yamt };
72 1.3.2.2 yamt
73 1.3.2.2 yamt static int coredump_buildname(struct proc *, char *, const char *, size_t);
74 1.3.2.2 yamt
75 1.3.2.2 yamt /*
76 1.3.2.2 yamt * Dump core, into a file named "progname.core" or "core" (depending on the
77 1.3.2.2 yamt * value of shortcorename), unless the process was setuid/setgid.
78 1.3.2.2 yamt */
79 1.3.2.2 yamt int
80 1.3.2.2 yamt coredump(struct lwp *l, const char *pattern)
81 1.3.2.2 yamt {
82 1.3.2.2 yamt struct vnode *vp;
83 1.3.2.2 yamt struct proc *p;
84 1.3.2.2 yamt struct vmspace *vm;
85 1.3.2.2 yamt kauth_cred_t cred;
86 1.3.2.2 yamt struct nameidata nd;
87 1.3.2.2 yamt struct vattr vattr;
88 1.3.2.2 yamt struct mount *mp;
89 1.3.2.2 yamt struct coredump_iostate io;
90 1.3.2.2 yamt int error, error1;
91 1.3.2.2 yamt char *name = NULL;
92 1.3.2.2 yamt
93 1.3.2.2 yamt p = l->l_proc;
94 1.3.2.2 yamt vm = p->p_vmspace;
95 1.3.2.2 yamt
96 1.3.2.2 yamt rw_enter(&proclist_lock, RW_READER); /* p_session */
97 1.3.2.2 yamt mutex_enter(&p->p_mutex);
98 1.3.2.2 yamt
99 1.3.2.2 yamt /*
100 1.3.2.2 yamt * Make sure the process has not set-id, to prevent data leaks,
101 1.3.2.2 yamt * unless it was specifically requested to allow set-id coredumps.
102 1.3.2.2 yamt */
103 1.3.2.2 yamt if ((p->p_flag & PK_SUGID) && !security_setidcore_dump) {
104 1.3.2.2 yamt mutex_exit(&p->p_mutex);
105 1.3.2.2 yamt rw_exit(&proclist_lock);
106 1.3.2.2 yamt return EPERM;
107 1.3.2.2 yamt }
108 1.3.2.2 yamt
109 1.3.2.2 yamt /*
110 1.3.2.2 yamt * Refuse to core if the data + stack + user size is larger than
111 1.3.2.2 yamt * the core dump limit. XXX THIS IS WRONG, because of mapped
112 1.3.2.2 yamt * data.
113 1.3.2.2 yamt */
114 1.3.2.2 yamt if (USPACE + ctob(vm->vm_dsize + vm->vm_ssize) >=
115 1.3.2.2 yamt p->p_rlimit[RLIMIT_CORE].rlim_cur) {
116 1.3.2.2 yamt mutex_exit(&p->p_mutex);
117 1.3.2.2 yamt rw_exit(&proclist_lock);
118 1.3.2.2 yamt return EFBIG; /* better error code? */
119 1.3.2.2 yamt }
120 1.3.2.2 yamt
121 1.3.2.2 yamt /*
122 1.3.2.2 yamt * It may well not be curproc, so grab a reference to its current
123 1.3.2.2 yamt * credentials.
124 1.3.2.2 yamt */
125 1.3.2.2 yamt kauth_cred_hold(p->p_cred);
126 1.3.2.2 yamt cred = p->p_cred;
127 1.3.2.2 yamt
128 1.3.2.2 yamt restart:
129 1.3.2.2 yamt /*
130 1.3.2.2 yamt * The core dump will go in the current working directory. Make
131 1.3.2.2 yamt * sure that the directory is still there and that the mount flags
132 1.3.2.2 yamt * allow us to write core dumps there.
133 1.3.2.2 yamt */
134 1.3.2.2 yamt vp = p->p_cwdi->cwdi_cdir;
135 1.3.2.2 yamt if (vp->v_mount == NULL ||
136 1.3.2.2 yamt (vp->v_mount->mnt_flag & MNT_NOCOREDUMP) != 0) {
137 1.3.2.2 yamt error = EPERM;
138 1.3.2.2 yamt mutex_exit(&p->p_mutex);
139 1.3.2.2 yamt rw_exit(&proclist_lock);
140 1.3.2.2 yamt goto done;
141 1.3.2.2 yamt }
142 1.3.2.2 yamt
143 1.3.2.2 yamt if ((p->p_flag & PK_SUGID) && security_setidcore_dump)
144 1.3.2.2 yamt pattern = security_setidcore_path;
145 1.3.2.2 yamt
146 1.3.2.2 yamt if (pattern == NULL)
147 1.3.2.2 yamt pattern = p->p_limit->pl_corename;
148 1.3.2.2 yamt if (name == NULL) {
149 1.3.2.2 yamt name = PNBUF_GET();
150 1.3.2.2 yamt }
151 1.3.2.2 yamt error = coredump_buildname(p, name, pattern, MAXPATHLEN);
152 1.3.2.2 yamt mutex_exit(&p->p_mutex);
153 1.3.2.2 yamt rw_exit(&proclist_lock);
154 1.3.2.2 yamt if (error)
155 1.3.2.2 yamt goto done;
156 1.3.2.2 yamt NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, l);
157 1.3.2.2 yamt if ((error = vn_open(&nd, O_CREAT | O_NOFOLLOW | FWRITE,
158 1.3.2.2 yamt S_IRUSR | S_IWUSR)) != 0)
159 1.3.2.2 yamt goto done;
160 1.3.2.2 yamt vp = nd.ni_vp;
161 1.3.2.2 yamt
162 1.3.2.2 yamt if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
163 1.3.2.2 yamt VOP_UNLOCK(vp, 0);
164 1.3.2.2 yamt if ((error = vn_close(vp, FWRITE, cred, l)) != 0)
165 1.3.2.2 yamt goto done;
166 1.3.2.2 yamt if ((error = vn_start_write(NULL, &mp,
167 1.3.2.2 yamt V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0)
168 1.3.2.2 yamt goto done;
169 1.3.2.2 yamt rw_enter(&proclist_lock, RW_READER); /* p_session */
170 1.3.2.2 yamt mutex_enter(&p->p_mutex);
171 1.3.2.2 yamt goto restart;
172 1.3.2.2 yamt }
173 1.3.2.2 yamt
174 1.3.2.2 yamt /* Don't dump to non-regular files or files with links. */
175 1.3.2.2 yamt if (vp->v_type != VREG ||
176 1.3.2.2 yamt VOP_GETATTR(vp, &vattr, cred, l) || vattr.va_nlink != 1) {
177 1.3.2.2 yamt error = EINVAL;
178 1.3.2.2 yamt goto out;
179 1.3.2.2 yamt }
180 1.3.2.2 yamt VATTR_NULL(&vattr);
181 1.3.2.2 yamt vattr.va_size = 0;
182 1.3.2.2 yamt
183 1.3.2.2 yamt if ((p->p_flag & PK_SUGID) && security_setidcore_dump) {
184 1.3.2.2 yamt vattr.va_uid = security_setidcore_owner;
185 1.3.2.2 yamt vattr.va_gid = security_setidcore_group;
186 1.3.2.2 yamt vattr.va_mode = security_setidcore_mode;
187 1.3.2.2 yamt }
188 1.3.2.2 yamt
189 1.3.2.2 yamt VOP_LEASE(vp, l, cred, LEASE_WRITE);
190 1.3.2.2 yamt VOP_SETATTR(vp, &vattr, cred, l);
191 1.3.2.2 yamt p->p_acflag |= ACORE;
192 1.3.2.2 yamt
193 1.3.2.2 yamt io.io_lwp = l;
194 1.3.2.2 yamt io.io_vp = vp;
195 1.3.2.2 yamt io.io_cred = cred;
196 1.3.2.2 yamt io.io_offset = 0;
197 1.3.2.2 yamt
198 1.3.2.2 yamt /* Now dump the actual core file. */
199 1.3.2.2 yamt error = (*p->p_execsw->es_coredump)(l, &io);
200 1.3.2.2 yamt out:
201 1.3.2.2 yamt VOP_UNLOCK(vp, 0);
202 1.3.2.2 yamt vn_finished_write(mp, 0);
203 1.3.2.2 yamt error1 = vn_close(vp, FWRITE, cred, l);
204 1.3.2.2 yamt if (error == 0)
205 1.3.2.2 yamt error = error1;
206 1.3.2.2 yamt done:
207 1.3.2.2 yamt if (name != NULL)
208 1.3.2.2 yamt PNBUF_PUT(name);
209 1.3.2.2 yamt return error;
210 1.3.2.2 yamt }
211 1.3.2.2 yamt
212 1.3.2.2 yamt static int
213 1.3.2.2 yamt coredump_buildname(struct proc *p, char *dst, const char *src, size_t len)
214 1.3.2.2 yamt {
215 1.3.2.2 yamt const char *s;
216 1.3.2.2 yamt char *d, *end;
217 1.3.2.2 yamt int i;
218 1.3.2.2 yamt
219 1.3.2.2 yamt LOCK_ASSERT(rw_read_held(&proclist_lock));
220 1.3.2.2 yamt
221 1.3.2.2 yamt for (s = src, d = dst, end = d + len; *s != '\0'; s++) {
222 1.3.2.2 yamt if (*s == '%') {
223 1.3.2.2 yamt switch (*(s + 1)) {
224 1.3.2.2 yamt case 'n':
225 1.3.2.2 yamt i = snprintf(d, end - d, "%s", p->p_comm);
226 1.3.2.2 yamt break;
227 1.3.2.2 yamt case 'p':
228 1.3.2.2 yamt i = snprintf(d, end - d, "%d", p->p_pid);
229 1.3.2.2 yamt break;
230 1.3.2.2 yamt case 'u':
231 1.3.2.2 yamt i = snprintf(d, end - d, "%.*s",
232 1.3.2.2 yamt (int)sizeof p->p_pgrp->pg_session->s_login,
233 1.3.2.2 yamt p->p_pgrp->pg_session->s_login);
234 1.3.2.2 yamt break;
235 1.3.2.2 yamt case 't':
236 1.3.2.2 yamt i = snprintf(d, end - d, "%ld",
237 1.3.2.2 yamt p->p_stats->p_start.tv_sec);
238 1.3.2.2 yamt break;
239 1.3.2.2 yamt default:
240 1.3.2.2 yamt goto copy;
241 1.3.2.2 yamt }
242 1.3.2.2 yamt d += i;
243 1.3.2.2 yamt s++;
244 1.3.2.2 yamt } else {
245 1.3.2.2 yamt copy: *d = *s;
246 1.3.2.2 yamt d++;
247 1.3.2.2 yamt }
248 1.3.2.2 yamt if (d >= end)
249 1.3.2.2 yamt return (ENAMETOOLONG);
250 1.3.2.2 yamt }
251 1.3.2.2 yamt *d = '\0';
252 1.3.2.2 yamt return 0;
253 1.3.2.2 yamt }
254 1.3.2.2 yamt
255 1.3.2.2 yamt int
256 1.3.2.2 yamt coredump_write(void *cookie, enum uio_seg segflg, const void *data, size_t len)
257 1.3.2.2 yamt {
258 1.3.2.2 yamt struct coredump_iostate *io = cookie;
259 1.3.2.2 yamt int error;
260 1.3.2.2 yamt
261 1.3.2.2 yamt error = vn_rdwr(UIO_WRITE, io->io_vp, __UNCONST(data), len,
262 1.3.2.2 yamt io->io_offset, segflg,
263 1.3.2.2 yamt IO_NODELOCKED|IO_UNIT, io->io_cred, NULL,
264 1.3.2.2 yamt segflg == UIO_USERSPACE ? io->io_lwp : NULL);
265 1.3.2.2 yamt if (error) {
266 1.3.2.2 yamt printf("pid %d (%s): %s write of %zu@%p at %lld failed: %d\n",
267 1.3.2.2 yamt io->io_lwp->l_proc->p_pid, io->io_lwp->l_proc->p_comm,
268 1.3.2.2 yamt segflg == UIO_USERSPACE ? "user" : "system",
269 1.3.2.2 yamt len, data, (long long) io->io_offset, error);
270 1.3.2.2 yamt return (error);
271 1.3.2.2 yamt }
272 1.3.2.2 yamt
273 1.3.2.2 yamt io->io_offset += len;
274 1.3.2.2 yamt return (0);
275 1.3.2.2 yamt }
276 1.3.2.2 yamt
277 1.3.2.2 yamt #endif /* COREDUMP */
278