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-rw-r--r--lib/util/fault.c307
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diff --git a/lib/util/fault.c b/lib/util/fault.c
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--- /dev/null
+++ b/lib/util/fault.c
@@ -0,0 +1,307 @@
+/*
+ Unix SMB/CIFS implementation.
+ Critical Fault handling
+ Copyright (C) Andrew Tridgell 1992-1998
+ Copyright (C) Tim Prouty 2009
+ Copyright (C) James Peach 2006
+
+ 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 "replace.h"
+#include "system/filesys.h"
+#include "system/wait.h"
+#include "version.h"
+
+#ifdef HAVE_SYS_SYSCTL_H
+#include <sys/sysctl.h>
+#endif
+
+
+#ifdef HAVE_SYS_PRCTL_H
+#include <sys/prctl.h>
+#endif
+
+#include "debug.h"
+#include "lib/util/signal.h" /* Avoid /usr/include/signal.h */
+#include "fault.h"
+
+static struct {
+ bool disabled;
+ smb_panic_handler_t panic_handler;
+} fault_state;
+
+
+/*******************************************************************
+setup variables used for fault handling
+********************************************************************/
+void fault_configure(smb_panic_handler_t panic_handler)
+{
+ fault_state.panic_handler = panic_handler;
+}
+
+
+/**
+ disable setting up fault handlers
+ This is used for the bind9 dlz module, as we
+ don't want a Samba module in bind9 to override the bind
+ fault handling
+**/
+_PUBLIC_ void fault_setup_disable(void)
+{
+ fault_state.disabled = true;
+}
+
+
+#if !defined(HAVE_DISABLE_FAULT_HANDLING)
+/*******************************************************************
+report a fault
+********************************************************************/
+static void fault_report(int sig)
+{
+ static int counter;
+ char signal_string[128];
+
+ if (counter) _exit(1);
+
+ counter++;
+
+ snprintf(signal_string, sizeof(signal_string),
+ "Signal %d: %s", sig, strsignal(sig));
+ smb_panic(signal_string);
+
+ /* smb_panic() never returns, so this is really redundant */
+ exit(1);
+}
+
+/****************************************************************************
+catch serious errors
+****************************************************************************/
+static void sig_fault(int sig)
+{
+ fault_report(sig);
+}
+#endif
+/*******************************************************************
+setup our fault handlers
+********************************************************************/
+void fault_setup(void)
+{
+ if (fault_state.disabled) {
+ return;
+ }
+#if !defined(HAVE_DISABLE_FAULT_HANDLING)
+#ifdef SIGSEGV
+ CatchSignal(SIGSEGV, sig_fault);
+#endif
+#ifdef SIGBUS
+ CatchSignal(SIGBUS, sig_fault);
+#endif
+#ifdef SIGABRT
+ CatchSignal(SIGABRT, sig_fault);
+#endif
+#endif
+}
+
+_PUBLIC_ const char *panic_action = NULL;
+
+/*
+ default smb_panic() implementation
+*/
+static void smb_panic_default(const char *why) _NORETURN_;
+static void smb_panic_default(const char *why)
+{
+#if defined(HAVE_PRCTL) && defined(PR_SET_PTRACER)
+ /*
+ * Make sure all children can attach a debugger.
+ */
+ prctl(PR_SET_PTRACER, getpid(), 0, 0, 0);
+#endif
+
+ if (panic_action && *panic_action) {
+ char cmdstring[200];
+ if (strlcpy(cmdstring, panic_action, sizeof(cmdstring)) < sizeof(cmdstring)) {
+ int result;
+ char pidstr[20];
+ char subst[200];
+ char *p = NULL;
+ snprintf(pidstr, sizeof(pidstr), "%d", (int) getpid());
+
+ p = strstr(cmdstring, "%d");
+ if (p != NULL) {
+ snprintf(subst,
+ sizeof(subst),
+ "%.*s%s%s",
+ (int)(p-cmdstring),
+ cmdstring,
+ pidstr,
+ p+2);
+ strlcpy(cmdstring, subst, sizeof(cmdstring));
+ }
+
+ DEBUG(0, ("smb_panic(): calling panic action [%s]\n", cmdstring));
+ result = system(cmdstring);
+
+ if (result == -1)
+ DEBUG(0, ("smb_panic(): fork failed in panic action: %s\n",
+ strerror(errno)));
+ else
+ DEBUG(0, ("smb_panic(): action returned status %d\n",
+ WEXITSTATUS(result)));
+ }
+ }
+
+#ifdef SIGABRT
+ CatchSignal(SIGABRT, SIG_DFL);
+#endif
+ abort();
+}
+
+_PUBLIC_ void smb_panic_log(const char *why)
+{
+ DEBUGSEP(0);
+ DEBUG(0,("INTERNAL ERROR: %s in pid %lld (%s)\n",
+ why,
+ (unsigned long long)getpid(),
+ SAMBA_VERSION_STRING));
+ DEBUG(0,("If you are running a recent Samba version, and "
+ "if you think this problem is not yet fixed in the "
+ "latest versions, please consider reporting this "
+ "bug, see "
+ "https://wiki.samba.org/index.php/Bug_Reporting\n"));
+ DEBUGSEP(0);
+ DEBUG(0,("PANIC (pid %llu): %s in " SAMBA_VERSION_STRING "\n",
+ (unsigned long long)getpid(), why));
+
+ log_stack_trace();
+}
+
+/**
+ Something really nasty happened - panic !
+**/
+_PUBLIC_ void smb_panic(const char *why)
+{
+ smb_panic_log(why);
+
+ if (fault_state.panic_handler) {
+ fault_state.panic_handler(why);
+ _exit(1);
+ }
+ smb_panic_default(why);
+}
+
+/*******************************************************************
+ Print a backtrace of the stack to the debug log. This function
+ DELIBERATELY LEAKS MEMORY. The expectation is that you should
+ exit shortly after calling it.
+********************************************************************/
+
+/* Buffer size to use when printing backtraces */
+#define BACKTRACE_STACK_SIZE 64
+
+
+#ifdef HAVE_LIBUNWIND_H
+#include <libunwind.h>
+#endif
+
+#ifdef HAVE_EXECINFO_H
+#include <execinfo.h>
+#endif
+
+void log_stack_trace(void)
+{
+#ifdef HAVE_LIBUNWIND
+ /*
+ * --with-libunwind is required to use libunwind, the
+ * backtrace_symbols() code below is the default.
+ *
+ * This code is available because a previous version of this
+ * comment asserted that on ia64 libunwind correctly walks the
+ * stack in more circumstances than backtrace.
+ */
+ unw_cursor_t cursor;
+ unw_context_t uc;
+ unsigned i = 0;
+
+ char procname[256];
+ unw_word_t ip, sp, off;
+
+ procname[sizeof(procname) - 1] = '\0';
+
+ if (unw_getcontext(&uc) != 0) {
+ goto libunwind_failed;
+ }
+
+ if (unw_init_local(&cursor, &uc) != 0) {
+ goto libunwind_failed;
+ }
+
+ DEBUG(0, ("BACKTRACE:\n"));
+
+ do {
+ ip = sp = 0;
+ unw_get_reg(&cursor, UNW_REG_IP, &ip);
+ unw_get_reg(&cursor, UNW_REG_SP, &sp);
+
+ switch (unw_get_proc_name(&cursor,
+ procname, sizeof(procname) - 1, &off) ) {
+ case 0:
+ /* Name found. */
+ case -UNW_ENOMEM:
+ /* Name truncated. */
+ DEBUGADD(0, (" #%u %s + %#llx [ip=%#llx] [sp=%#llx]\n",
+ i, procname, (long long)off,
+ (long long)ip, (long long) sp));
+ break;
+ default:
+ /* case -UNW_ENOINFO: */
+ /* case -UNW_EUNSPEC: */
+ /* No symbol name found. */
+ DEBUGADD(0, (" #%u %s [ip=%#llx] [sp=%#llx]\n",
+ i, "<unknown symbol>",
+ (long long)ip, (long long) sp));
+ }
+ ++i;
+ } while (unw_step(&cursor) > 0);
+
+ return;
+
+libunwind_failed:
+ DEBUG(0, ("unable to produce a stack trace with libunwind\n"));
+
+#elif defined(HAVE_BACKTRACE_SYMBOLS)
+ void *backtrace_stack[BACKTRACE_STACK_SIZE];
+ size_t backtrace_size;
+ char **backtrace_strings;
+
+ /* get the backtrace (stack frames) */
+ backtrace_size = backtrace(backtrace_stack,BACKTRACE_STACK_SIZE);
+ backtrace_strings = backtrace_symbols(backtrace_stack, backtrace_size);
+
+ DEBUG(0, ("BACKTRACE: %lu stack frames:\n",
+ (unsigned long)backtrace_size));
+
+ if (backtrace_strings) {
+ size_t i;
+
+ for (i = 0; i < backtrace_size; i++)
+ DEBUGADD(0, (" #%zu %s\n", i, backtrace_strings[i]));
+
+ /* Leak the backtrace_strings, rather than risk what free() might do */
+ }
+
+#else
+ DEBUG(0, ("unable to produce a stack trace on this platform\n"));
+#endif
+}
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