Adding upstream version 2:4.17.12+dfsg.upstream/2%4.17.12+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 307 insertions, 0 deletions

diff --git a/lib/util/fault.c b/lib/util/fault.c
new file mode 100644
index 0000000..3b1d10d
--- /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
+}