/* Unix SMB/CIFS implementation. Critical Fault handling Copyright (C) Andrew Tridgell 1992-1998 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include "includes.h" #ifdef HAVE_SYS_PRCTL_H #include <sys/prctl.h> #endif static void (*cont_fn)(void *); static char *corepath; /******************************************************************* report a fault ********************************************************************/ static void fault_report(int sig) { static int counter; if (counter) _exit(1); counter++; DEBUGSEP(0); DEBUG(0,("INTERNAL ERROR: Signal %d in pid %d (%s)",sig,(int)sys_getpid(),SAMBA_VERSION_STRING)); DEBUG(0,("\nPlease read the Trouble-Shooting section of the Samba3-HOWTO\n")); DEBUG(0,("\nFrom: http://www.samba.org/samba/docs/Samba3-HOWTO.pdf\n")); DEBUGSEP(0); smb_panic("internal error"); if (cont_fn) { cont_fn(NULL); #ifdef SIGSEGV CatchSignal(SIGSEGV,SIGNAL_CAST SIG_DFL); #endif #ifdef SIGBUS CatchSignal(SIGBUS,SIGNAL_CAST SIG_DFL); #endif #ifdef SIGABRT CatchSignal(SIGABRT,SIGNAL_CAST SIG_DFL); #endif return; /* this should cause a core dump */ } exit(1); } /**************************************************************************** catch serious errors ****************************************************************************/ static void sig_fault(int sig) { fault_report(sig); } /******************************************************************* setup our fault handlers ********************************************************************/ void fault_setup(void (*fn)(void *)) { cont_fn = fn; #ifdef SIGSEGV CatchSignal(SIGSEGV,SIGNAL_CAST sig_fault); #endif #ifdef SIGBUS CatchSignal(SIGBUS,SIGNAL_CAST sig_fault); #endif #ifdef SIGABRT CatchSignal(SIGABRT,SIGNAL_CAST sig_fault); #endif } /******************************************************************* make all the preparations to safely dump a core file ********************************************************************/ void dump_core_setup(const char *progname) { char *logbase = NULL; char *end = NULL; if (lp_logfile() && *lp_logfile()) { if (asprintf(&logbase, "%s", lp_logfile()) < 0) { return; } if ((end = strrchr_m(logbase, '/'))) { *end = '\0'; } } else { /* We will end up here is the log file is given on the command * line by the -l option but the "log file" option is not set * in smb.conf. */ if (asprintf(&logbase, "%s", get_dyn_LOGFILEBASE()) < 0) { return; } } SMB_ASSERT(progname != NULL); if (asprintf(&corepath, "%s/cores", logbase) < 0) { SAFE_FREE(logbase); return; } mkdir(corepath,0700); SAFE_FREE(corepath); if (asprintf(&corepath, "%s/cores/%s", logbase, progname) < 0) { SAFE_FREE(logbase); return; } mkdir(corepath,0700); sys_chown(corepath,getuid(),getgid()); chmod(corepath,0700); SAFE_FREE(logbase); #ifdef HAVE_GETRLIMIT #ifdef RLIMIT_CORE { struct rlimit rlp; getrlimit(RLIMIT_CORE, &rlp); rlp.rlim_cur = MAX(16*1024*1024,rlp.rlim_cur); setrlimit(RLIMIT_CORE, &rlp); getrlimit(RLIMIT_CORE, &rlp); DEBUG(3,("Maximum core file size limits now %d(soft) %d(hard)\n", (int)rlp.rlim_cur,(int)rlp.rlim_max)); } #endif #endif #if defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE) /* On Linux we lose the ability to dump core when we change our user * ID. We know how to dump core safely, so let's make sure we have our * dumpable flag set. */ prctl(PR_SET_DUMPABLE, 1); #endif /* FIXME: if we have a core-plus-pid facility, configurably set * this up here. */ } void dump_core(void) { static bool called; if (called) { DEBUG(0, ("dump_core() called recursive\n")); exit(1); } called = true; /* Note that even if core dumping has been disabled, we still set up * the core path. This is to handle the case where core dumping is * turned on in smb.conf and the relevant daemon is not restarted. */ if (!lp_enable_core_files()) { DEBUG(0, ("Exiting on internal error (core file administratively disabled)\n")); exit(1); } #if DUMP_CORE /* If we're running as non root we might not be able to dump the core * file to the corepath. There must not be an unbecome_root() before * we call abort(). */ if (geteuid() != 0) { become_root(); } if (corepath == NULL) { DEBUG(0, ("Can not dump core: corepath not set up\n")); exit(1); } if (*corepath != '\0') { /* The chdir might fail if we dump core before we finish * processing the config file. */ if (chdir(corepath) != 0) { DEBUG(0, ("unable to change to %s\n", corepath)); DEBUGADD(0, ("refusing to dump core\n")); exit(1); } DEBUG(0,("dumping core in %s\n", corepath)); } umask(~(0700)); dbgflush(); /* Ensure we don't have a signal handler for abort. */ #ifdef SIGABRT CatchSignal(SIGABRT,SIGNAL_CAST SIG_DFL); #endif abort(); #else /* DUMP_CORE */ exit(1); #endif /* DUMP_CORE */ }