Lock around variables retrieved, and copy the values, if they stay persistent,

since another thread could remove them.
(closes issue #12541)
 Reported by: snuffy
 Patches: 
       bug_12156_apps.diff uploaded by snuffy (license 35)
       Several additional changes by me


git-svn-id: http://svn.digium.com/svn/asterisk/trunk@114904 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 26 insertions, 8 deletions

diff --git a/apps/app_minivm.c b/apps/app_minivm.c
index 8a66a9579..8746aca5b 100644
--- a/apps/app_minivm.c
+++ b/apps/app_minivm.c
@@ -1412,7 +1412,12 @@ static int notify_new_message(struct ast_channel *chan, const char *templatename
 
 
 	/* Read counter if available */
-	counter = pbx_builtin_getvar_helper(chan, "MVM_COUNTER");
+	ast_channel_lock(chan);
+	if ((counter = pbx_builtin_getvar_helper(chan, "MVM_COUNTER"))) {
+		counter = ast_strdupa(counter);
+	}
+	ast_channel_unlock(chan);
+
 	if (ast_strlen_zero(counter)) {
 		ast_debug(2, "-_-_- MVM_COUNTER not found\n");
 	} else {
@@ -1659,14 +1664,24 @@ static int minivm_notify_exec(struct ast_channel *chan, void *data)
 		pbx_builtin_setvar_helper(chan, "MINIVM_NOTIFY_STATUS", "FAILED");
 		return -1;
 	}
-	
-	filename = pbx_builtin_getvar_helper(chan, "MVM_FILENAME");
-	format = pbx_builtin_getvar_helper(chan, "MVM_FORMAT");
-	duration_string = pbx_builtin_getvar_helper(chan, "MVM_DURATION");
+
+	ast_channel_lock(chan);
+	if ((filename = pbx_builtin_getvar_helper(chan, "MVM_FILENAME"))) {
+		filename = ast_strdupa(filename);
+	}
+	ast_channel_unlock(chan);
 	/* Notify of new message to e-mail and pager */
 	if (!ast_strlen_zero(filename)) {
+		ast_channel_lock(chan);	
+		if ((format = pbx_builtin_getvar_helper(chan, "MVM_FORMAT"))) {
+			format = ast_strdupa(format);
+		}
+		if ((duration_string = pbx_builtin_getvar_helper(chan, "MVM_DURATION"))) {
+			duration_string = ast_strdupa(duration_string);
+		}
+		ast_channel_unlock(chan);
 		res = notify_new_message(chan, template, vmu, filename, atoi(duration_string), format, chan->cid.cid_num, chan->cid.cid_name);
-	};
+	}
 
 	pbx_builtin_setvar_helper(chan, "MINIVM_NOTIFY_STATUS", res == 0 ? "SUCCESS" : "FAILED");
 
@@ -1928,10 +1943,13 @@ static int minivm_delete_exec(struct ast_channel *chan, void *data)
 	int res = 0;
 	char filename[BUFSIZ];
 		
-	if (!ast_strlen_zero(data))
+	if (!ast_strlen_zero(data)) {
 		ast_copy_string(filename, (char *) data, sizeof(filename));
-	else
+	} else {
+		ast_channel_lock(chan);
 		ast_copy_string(filename, pbx_builtin_getvar_helper(chan, "MVM_FILENAME"), sizeof(filename));
+		ast_channel_unlock(chan);
+	}
 
 	if (ast_strlen_zero(filename)) {
 		ast_log(LOG_ERROR, "No filename given in application arguments or channel variable MVM_FILENAME\n");