talons

commit cfbe405f11fd8e87b13c34ba4c00a4ee5cffcd32
parent 57e6203525cd1238f5f7164ba2587c50a603d2c4
Author: Andrej Kacian <ticho@claws-mail.org>
Date:   Sun, 16 Jul 2017 12:18:03 +0200

Second attempt at fixing the memory leak in matcherrc rule parsing.

This time, we take into account that the memory allocated by
yyparse() uses is sometimes used and freed by another
function higher in the stack.

Diffstat:
M
src/matcher_parser_parse.y
 | 
15
+++++++++++++++

1 file changed, 15 insertions(+), 0 deletions(-)
diff --git a/src/matcher_parser_parse.y b/src/matcher_parser_parse.y
@@ -50,6 +50,7 @@ static gboolean matcher_is_fast = TRUE;
 static gboolean disable_warnings = FALSE;
 
 static FilteringProp *filtering;
+static gboolean filtering_ptr_externally_managed = FALSE;
 
 static GSList **prefs_filtering = NULL;
 static int enable_compatibility = 0;
@@ -112,11 +113,16 @@ FilteringProp *matcher_parser_get_filtering(gchar *str)
         matcher_parser_init();
 	bufstate = matcher_parser_scan_string((const char *) tmp_str);
         matcher_parser_switch_to_buffer(bufstate);
+	/* Indicate that we will be using the global "filtering" pointer,
+	 * so that yyparse does not free it in "filtering_action_list"
+	 * section. */
+	filtering_ptr_externally_managed = TRUE;
 	if (matcher_parserparse() != 0)
 		filtering = NULL;
 	matcher_parse_op = MATCHER_PARSE_FILE;
 	matcher_parser_delete_buffer(bufstate);
 	g_free(tmp_str);
+	filtering_ptr_externally_managed = FALSE; /* Return to normal. */
 	return filtering;
 }
 
@@ -537,6 +543,15 @@ filtering_action_list
 		*prefs_filtering = g_slist_append(*prefs_filtering,
 						  filtering);
 		filtering = NULL;
+	} else if (!filtering_ptr_externally_managed) {
+		/* If filtering_ptr_externally_managed was TRUE, it
+		 * would mean that some function higher in the stack is
+		 * interested in the data "filtering" is pointing at, so
+		 * we would not free it. That function has to free it itself.
+		 * At the time of writing this, the only function that
+		 * does this is matcher_parser_get_filtering(). */
+		filteringprop_free(filtering);
+		filtering = NULL;
 	}
 }
 ;