2 Unix SMB/CIFS implementation.
3 Samba utility functions
5 Copyright (C) Andrew Tridgell 1992-2011
7 based on old fault.c code, which had:
9 Copyright (C) Jeremy Allison 2001-2007
10 Copyright (C) Simo Sorce 2001
11 Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2003
12 Copyright (C) James Peach 2006
14 This program is free software; you can redistribute it and/or modify
15 it under the terms of the GNU General Public License as published by
16 the Free Software Foundation; either version 3 of the License, or
17 (at your option) any later version.
19 This program is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 GNU General Public License for more details.
24 You should have received a copy of the GNU General Public License
25 along with this program. If not, see <http://www.gnu.org/licenses/>.
29 #include "system/filesys.h"
31 #ifdef HAVE_SYS_SYSCTL_H
32 #include <sys/sysctl.h>
35 #ifdef HAVE_SYS_PRCTL_H
36 #include <sys/prctl.h>
39 static char *corepath;
42 * Build up the default corepath as "<logbase>/cores/<progname>"
44 static char *get_default_corepath(const char *logbase, const char *progname)
48 /* Setup core dir in logbase. */
49 tmp_corepath = talloc_asprintf(NULL, "%s/cores", logbase);
53 if ((mkdir(tmp_corepath, 0700) == -1) && errno != EEXIST)
56 if (chmod(tmp_corepath, 0700) == -1)
59 talloc_free(tmp_corepath);
61 /* Setup progname-specific core subdir */
62 tmp_corepath = talloc_asprintf(NULL, "%s/cores/%s", logbase, progname);
66 if (mkdir(tmp_corepath, 0700) == -1 && errno != EEXIST)
69 if (chown(tmp_corepath, getuid(), getgid()) == -1)
72 if (chmod(tmp_corepath, 0700) == -1)
78 talloc_free(tmp_corepath);
84 * Get the FreeBSD corepath.
86 * On FreeBSD the current working directory is ignored when creating a core
87 * file. Instead the core directory is controlled via sysctl. This consults
88 * the value of "kern.corefile" so the correct corepath can be printed out
89 * before dump_core() calls abort.
91 #if (defined(FREEBSD) && defined(HAVE_SYSCTLBYNAME))
92 static char *get_freebsd_corepath(void)
94 char *tmp_corepath = NULL;
99 /* Loop with increasing sizes so we don't allocate too much. */
105 tmp_corepath = (char *)talloc_realloc(NULL, tmp_corepath,
111 ret = sysctlbyname("kern.corefile", tmp_corepath, &len, NULL,
114 if (errno != ENOMEM) {
115 DEBUG(0, ("sysctlbyname failed getting "
116 "kern.corefile %s\n",
121 /* Not a large enough array, try a bigger one. */
126 /* Strip off the common filename expansion */
127 if ((end = strrchr_m(tmp_corepath, '/'))) {
135 talloc_free(tmp_corepath);
141 #if defined(HAVE_SYS_KERNEL_PROC_CORE_PATTERN)
144 * Get the Linux corepath.
146 * On Linux the contents of /proc/sys/kernel/core_pattern indicates the
147 * location of the core path.
149 static char *get_linux_corepath(void)
155 fd = open("/proc/sys/kernel/core_pattern", O_RDONLY, 0);
160 result = afdgets(fd, NULL, 0);
163 if (result == NULL) {
167 if (result[0] != '/') {
169 * No absolute path, use the default (cwd)
174 /* Strip off the common filename expansion */
176 end = strrchr_m(result, '/');
178 if ((end != result) /* this would be the only / */
188 * Try getting system-specific corepath if one exists.
190 * If the system doesn't define a corepath, then the default is used.
192 static char *get_corepath(const char *logbase, const char *progname)
194 #if (defined(FREEBSD) && defined(HAVE_SYSCTLBYNAME))
195 char *tmp_corepath = NULL;
196 tmp_corepath = get_freebsd_corepath();
198 /* If this has been set correctly, we're done. */
204 #if defined(HAVE_SYS_KERNEL_PROC_CORE_PATTERN)
205 char *tmp_corepath = NULL;
206 tmp_corepath = get_linux_corepath();
208 /* If this has been set correctly, we're done. */
214 /* Fall back to the default. */
215 return get_default_corepath(logbase, progname);
218 /*******************************************************************
219 make all the preparations to safely dump a core file
220 ********************************************************************/
222 void dump_core_setup(const char *progname, const char *log_file)
224 char *logbase = NULL;
227 if (log_file && *log_file) {
228 if (asprintf(&logbase, "%s", log_file) < 0) {
231 if ((end = strrchr_m(logbase, '/'))) {
235 /* We will end up here if the log file is given on the command
236 * line by the -l option but the "log file" option is not set
239 if (asprintf(&logbase, "%s", get_dyn_LOGFILEBASE()) < 0) {
244 SMB_ASSERT(progname != NULL);
246 corepath = get_corepath(logbase, progname);
248 DEBUG(0, ("Unable to setup corepath for %s: %s\n", progname,
254 #ifdef HAVE_GETRLIMIT
258 getrlimit(RLIMIT_CORE, &rlp);
259 rlp.rlim_cur = MAX(16*1024*1024,rlp.rlim_cur);
260 setrlimit(RLIMIT_CORE, &rlp);
261 getrlimit(RLIMIT_CORE, &rlp);
262 DEBUG(3,("Maximum core file size limits now %d(soft) %d(hard)\n",
263 (int)rlp.rlim_cur,(int)rlp.rlim_max));
268 /* FIXME: if we have a core-plus-pid facility, configurably set
280 DEBUG(0, ("dump_core() called recursive\n"));
285 /* Note that even if core dumping has been disabled, we still set up
286 * the core path. This is to handle the case where core dumping is
287 * turned on in smb.conf and the relevant daemon is not restarted.
289 if (!lp_enable_core_files()) {
290 DEBUG(0, ("Exiting on internal error (core file administratively disabled)\n"));
295 /* If we're running as non root we might not be able to dump the core
296 * file to the corepath. There must not be an unbecome_root() before
297 * we call abort(). */
298 if (geteuid() != sec_initial_uid()) {
302 if (corepath == NULL) {
303 DEBUG(0, ("Can not dump core: corepath not set up\n"));
307 if (*corepath != '\0') {
308 /* The chdir might fail if we dump core before we finish
309 * processing the config file.
311 if (chdir(corepath) != 0) {
312 DEBUG(0, ("unable to change to %s\n", corepath));
313 DEBUGADD(0, ("refusing to dump core\n"));
317 DEBUG(0,("dumping core in %s\n", corepath));
323 #if defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE)
324 /* On Linux we lose the ability to dump core when we change our user
325 * ID. We know how to dump core safely, so let's make sure we have our
328 prctl(PR_SET_DUMPABLE, 1);
331 /* Ensure we don't have a signal handler for abort. */
333 CatchSignal(SIGABRT, SIG_DFL);
338 #else /* DUMP_CORE */
340 #endif /* DUMP_CORE */