From: Jonathan Rose <jrose@digium.com>
Date: Fri, 14 Jun 2013 16:14:48 +0000 (+0000)
Subject: app_mixmonitor: Fix crashes caused by unloading app_mixmonitor
X-Git-Tag: 1.8.24.0-rc1~68
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=0630ac71c27cadad1dfdf8395675746a49f27a42;p=thirdparty%2Fasterisk.git

app_mixmonitor: Fix crashes caused by unloading app_mixmonitor

Unloading app_mixmonitor while active mixmonitors were running would
cause a segfault. This patch fixes that by making it impossible to
unload app_mixmonitor while mixmonitors are active.

Review: https://reviewboard.asterisk.org/r/2624/


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@391778 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---

diff --git a/apps/app_mixmonitor.c b/apps/app_mixmonitor.c
index a9a4aa46fa..f13edc6ed8 100644
--- a/apps/app_mixmonitor.c
+++ b/apps/app_mixmonitor.c
@@ -381,6 +381,8 @@ static void *mixmonitor_thread(void *obj)
 
 	ast_verb(2, "End MixMonitor Recording %s\n", mixmonitor->name);
 	mixmonitor_free(mixmonitor);
+
+	ast_module_unref(ast_module_info->self);
 	return NULL;
 }
 
@@ -414,7 +416,7 @@ static int setup_mixmonitor_ds(struct mixmonitor *mixmonitor, struct ast_channel
 	return 0;
 }
 
-static void launch_monitor_thread(struct ast_channel *chan, const char *filename, unsigned int flags,
+static int launch_monitor_thread(struct ast_channel *chan, const char *filename, unsigned int flags,
 				  int readvol, int writevol, const char *post_process) 
 {
 	pthread_t thread;
@@ -442,26 +444,26 @@ static void launch_monitor_thread(struct ast_channel *chan, const char *filename
 
 	/* Pre-allocate mixmonitor structure and spy */
 	if (!(mixmonitor = ast_calloc(1, len))) {
-		return;
+		return -1;
 	}
 
 	/* Setup the actual spy before creating our thread */
 	if (ast_audiohook_init(&mixmonitor->audiohook, AST_AUDIOHOOK_TYPE_SPY, mixmonitor_spy_type)) {
 		mixmonitor_free(mixmonitor);
-		return;
+		return -1;
 	}
 
 	/* Copy over flags and channel name */
 	mixmonitor->flags = flags;
 	if (!(mixmonitor->autochan = ast_autochan_setup(chan))) {
 		mixmonitor_free(mixmonitor);
-		return;
+		return -1;
 	}
 
 	if (setup_mixmonitor_ds(mixmonitor, chan)) {
 		ast_autochan_destroy(mixmonitor->autochan);
 		mixmonitor_free(mixmonitor);
-		return;
+		return -1;
 	}
 	mixmonitor->name = (char *) mixmonitor + sizeof(*mixmonitor);
 	strcpy(mixmonitor->name, chan->name);
@@ -485,10 +487,10 @@ static void launch_monitor_thread(struct ast_channel *chan, const char *filename
 			mixmonitor_spy_type, chan->name);
 		ast_audiohook_destroy(&mixmonitor->audiohook);
 		mixmonitor_free(mixmonitor);
-		return;
+		return -1;
 	}
 
-	ast_pthread_create_detached_background(&thread, NULL, mixmonitor_thread, mixmonitor);
+	return ast_pthread_create_detached_background(&thread, NULL, mixmonitor_thread, mixmonitor);
 }
 
 static int mixmonitor_exec(struct ast_channel *chan, const char *data)
@@ -567,7 +569,12 @@ static int mixmonitor_exec(struct ast_channel *chan, const char *data)
 	ast_mkdir(tmp, 0777);
 
 	pbx_builtin_setvar_helper(chan, "MIXMONITOR_FILENAME", args.filename);
-	launch_monitor_thread(chan, args.filename, flags.flags, readvol, writevol, args.post_process);
+
+	/* If launch_monitor_thread works, the module reference must not be released until it is finished. */
+	ast_module_ref(ast_module_info->self);
+	if (launch_monitor_thread(chan, args.filename, flags.flags, readvol, writevol, args.post_process)) {
+		ast_module_unref(ast_module_info->self);
+	}
 
 	return 0;
 }