From: Arran Cudbard-Bell <a.cudbardb@freeradius.org>
Date: Wed, 8 Jun 2016 15:12:32 +0000 (-0400)
Subject: Prevent signal loop
X-Git-Tag: release_3_0_12~126
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=442b8f27d3ba8e460c871cb0abc593d39442e12d;p=thirdparty%2Ffreeradius-server.git

Prevent signal loop

Conflicts:
	src/include/libradius.h
	src/lib/misc.c
---

diff --git a/src/include/libradius.h b/src/include/libradius.h
index 545be09dfca..9626864e718 100644
--- a/src/include/libradius.h
+++ b/src/include/libradius.h
@@ -703,6 +703,7 @@ void		fr_printf_log(char const *, ...) CC_HINT(format (printf, 1, 2));
  *	Several handy miscellaneous functions.
  */
 int		fr_set_signal(int sig, sig_t func);
+int		fr_unset_signal(int sig);
 int		fr_link_talloc_ctx_free(TALLOC_CTX *parent, TALLOC_CTX *child);
 char const	*fr_inet_ntop(int af, void const *src);
 char const 	*ip_ntoa(char *, uint32_t);
diff --git a/src/lib/debug.c b/src/lib/debug.c
index 151b4f664ab..2a034a48a32 100644
--- a/src/lib/debug.c
+++ b/src/lib/debug.c
@@ -703,11 +703,11 @@ NEVER_RETURNS void fr_fault(int sig)
 	if (strlen(p) >= left) goto oob;
 	strlcpy(out, p, left);
 
-	FR_FAULT_LOG("Calling: %s", cmd);
-
 	{
 		bool disable = false;
 
+		FR_FAULT_LOG("Calling: %s", cmd);
+
 		/*
 		 *	Here we temporarily enable the dumpable flag so if GBD or LLDB
 		 *	is called in the panic_action, they can pattach to the running
@@ -738,13 +738,23 @@ NEVER_RETURNS void fr_fault(int sig)
 			}
 		}
 
-		fr_exit_now(1);
+		FR_FAULT_LOG("Panic action exited with %i", code);
+
+		fr_exit_now(code);
 	}
 
-	FR_FAULT_LOG("Panic action exited with %i", code);
 
 finish:
+	/*
+	 *	(Re-)Raise the signal, so that if we're running under
+	 *	a debugger, the debugger can break when it receives
+	 *	the signal.
+	 */
+	fr_unset_signal(sig);	/* Make sure we don't get into a loop */
+
 	raise(sig);
+
+	fr_exit_now(1);		/* Function marked as noreturn */
 }
 
 /** Callback executed on fatal talloc error
diff --git a/src/lib/misc.c b/src/lib/misc.c
index 5ef00fe4dd1..8ed9e3a182b 100644
--- a/src/lib/misc.c
+++ b/src/lib/misc.c
@@ -80,6 +80,28 @@ int fr_set_signal(int sig, sig_t func)
 	return 0;
 }
 
+/** Uninstall a signal for a specific handler
+ *
+ * man sigaction says these are fine to call from a signal handler.
+ *
+ * @param sig SIGNAL
+ */
+int fr_unset_signal(int sig)
+{
+#ifdef HAVE_SIGACTION
+        struct sigaction act;
+
+        memset(&act, 0, sizeof(act));
+        act.sa_flags = 0;
+        sigemptyset(&act.sa_mask);
+        act.sa_handler = SIG_DFL;
+
+        return sigaction(sig, &act, NULL);
+#else
+        return signal(sig, SIG_DFLT);
+#endif
+}
+
 static int _fr_trigger_talloc_ctx_free(fr_talloc_link_t *trigger)
 {
 	if (trigger->armed) talloc_free(trigger->child);
@@ -322,7 +344,7 @@ int fr_pton4(fr_ipaddr_t *out, char const *value, ssize_t inlen, bool resolve, b
 
 		return 0;
 	}
-	
+
 	/*
 	 *	Copy the IP portion into a temporary buffer if we haven't already.
 	 */