dfilter: Fixup deprecated tokens initialization

Always use the internal API to access "deprecated" and initialize
the data structure on demand. This fixes a null pointer dereference
introduced previously.

Use reference counting to share the array cleanly and avoid memory
leaks.

Keep the pointer in dfwork_t.

4 files changed, 23 insertions, 41 deletions

diff --git a/epan/dfilter/dfilter-int.h b/epan/dfilter/dfilter-int.h
index eff2946d98..9e6cef482c 100644
--- a/epan/dfilter/dfilter-int.h
+++ b/epan/dfilter/dfilter-int.h
@@ -53,7 +53,6 @@ typedef struct {
 	GString* quoted_string;
 	gboolean raw_string;
 	gboolean in_set;	/* true if parsing set elements for the membership operator */
-	GPtrArray *deprecated;
 } df_scanner_state_t;
 
 /* Constructor/Destructor prototypes for Lemon Parser */
@@ -76,7 +75,7 @@ void
 dfilter_parse_fail(dfwork_t *dfw, const char *format, ...) G_GNUC_PRINTF(2, 3);
 
 void
-add_deprecated_token(GPtrArray *deprecated, const char *token);
+add_deprecated_token(dfwork_t *dfw, const char *token);
 
 void
 free_deprecated(GPtrArray *deprecated);
diff --git a/epan/dfilter/dfilter.c b/epan/dfilter/dfilter.c
index e2a1a37069..1c47caa5a6 100644
--- a/epan/dfilter/dfilter.c
+++ b/epan/dfilter/dfilter.c
@@ -153,7 +153,7 @@ dfilter_resolve_unparsed(dfwork_t *dfw, stnode_t *node)
 	hfinfo = proto_registrar_get_byalias(name);
 	if (hfinfo != NULL) {
 		/* It's an aliased field name */
-		add_deprecated_token(dfw->deprecated, name);
+		add_deprecated_token(dfw, name);
 		stnode_replace(node, STTYPE_FIELD, hfinfo);
 		return node;
 	}
@@ -204,13 +204,15 @@ dfilter_cleanup(void)
 }
 
 static dfilter_t*
-dfilter_new(void)
+dfilter_new(GPtrArray *deprecated)
 {
 	dfilter_t	*df;
 
 	df = g_new0(dfilter_t, 1);
 	df->insns = NULL;
-	df->deprecated = NULL;
+
+	if (deprecated)
+		df->deprecated = g_ptr_array_ref(deprecated);
 
 	return df;
 }
@@ -253,13 +255,8 @@ dfilter_free(dfilter_t *df)
 		g_list_free(df->registers[i]);
 	}
 
-	if (df->deprecated) {
-		for (i = 0; i < df->deprecated->len; ++i) {
-			gchar *depr = (gchar *)g_ptr_array_index(df->deprecated, i);
-			g_free(depr);
-		}
-		g_ptr_array_free(df->deprecated, TRUE);
-	}
+	if (df->deprecated)
+		g_ptr_array_unref(df->deprecated);
 
 	g_free(df->registers);
 	g_free(df->attempted_load);
@@ -302,6 +299,9 @@ dfwork_free(dfwork_t *dfw)
 		free_insns(dfw->consts);
 	}
 
+	if (dfw->deprecated)
+		g_ptr_array_unref(dfw->deprecated);
+
 	/*
 	 * We don't free the error message string; our caller will return
 	 * it to its caller.
@@ -346,10 +346,15 @@ const char *tokenstr(int token)
 }
 
 void
-add_deprecated_token(GPtrArray *deprecated, const char *token)
+add_deprecated_token(dfwork_t *dfw, const char *token)
 {
+	if (dfw->deprecated == NULL)
+		dfw->deprecated  = g_ptr_array_new_full(0, g_free);
+
+	GPtrArray *deprecated = dfw->deprecated;
+
 	for (guint i = 0; i < deprecated->len; i++) {
-		const char *str = (const char *)g_ptr_array_index(deprecated, i);
+		const char *str = g_ptr_array_index(deprecated, i);
 		if (g_ascii_strcasecmp(token, str) == 0) {
 			/* It's already in our list */
 			return;
@@ -358,16 +363,6 @@ add_deprecated_token(GPtrArray *deprecated, const char *token)
 	g_ptr_array_add(deprecated, g_strdup(token));
 }
 
-void
-free_deprecated(GPtrArray *deprecated)
-{
-	for (guint i = 0; i < deprecated->len; ++i) {
-		gpointer *depr = g_ptr_array_index(deprecated,i);
-		g_free(depr);
-	}
-	g_ptr_array_free(deprecated, TRUE);
-}
-
 gboolean
 dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)
 {
@@ -379,8 +374,6 @@ dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)
 	yyscan_t	scanner;
 	YY_BUFFER_STATE in_buffer;
 	gboolean failure = FALSE;
-	/* XXX, GHashTable */
-	GPtrArray	*deprecated;
 
 	ws_assert(dfp);
 
@@ -409,13 +402,10 @@ dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)
 
 	dfw = dfwork_new();
 
-	deprecated = g_ptr_array_new();
-
 	state.dfw = dfw;
 	state.quoted_string = NULL;
 	state.in_set = FALSE;
 	state.raw_string = FALSE;
-	state.deprecated = deprecated;
 
 	df_set_extra(&state, scanner);
 
@@ -480,13 +470,10 @@ dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)
 	 * it and set *dfp to NULL */
 	if (dfw->st_root == NULL) {
 		*dfp = NULL;
-		free_deprecated(deprecated);
 	}
 	else {
 		log_syntax_tree(LOG_LEVEL_NOISY, dfw->st_root, "Syntax tree before semantic check");
 
-		dfw->deprecated = deprecated;
-
 		/* Check semantics and do necessary type conversion*/
 		if (!dfw_semcheck(dfw)) {
 			goto FAILURE;
@@ -498,7 +485,7 @@ dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)
 		dfw_gencode(dfw);
 
 		/* Tuck away the bytecode in the dfilter_t */
-		dfilter = dfilter_new();
+		dfilter = dfilter_new(dfw->deprecated);
 		dfilter->insns = dfw->insns;
 		dfilter->consts = dfw->consts;
 		dfw->insns = NULL;
@@ -516,9 +503,6 @@ dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)
 		/* Initialize constants */
 		dfvm_init_const(dfilter);
 
-		/* Add any deprecated items */
-		dfilter->deprecated = deprecated;
-
 		/* And give it to the user. */
 		*dfp = dfilter;
 	}
@@ -537,7 +521,6 @@ FAILURE:
 		global_dfw = NULL;
 		dfwork_free(dfw);
 	}
-	free_deprecated(deprecated);
 	if (err_msg != NULL) {
 		/*
 		 * Default error message.
diff --git a/epan/dfilter/scanner.l b/epan/dfilter/scanner.l
index 8a5c00b9c7..450d4564c9 100644
--- a/epan/dfilter/scanner.l
+++ b/epan/dfilter/scanner.l
@@ -137,11 +137,11 @@ static int simple(int token, const char *token_value);
 "=="		return SIMPLE(TOKEN_TEST_EQ);
 "eq"		return SIMPLE(TOKEN_TEST_EQ);
 "!="			{
-	add_deprecated_token(yyextra->deprecated, "!=");
+	add_deprecated_token(yyextra->dfw, "!=");
 	return SIMPLE(TOKEN_TEST_NE);
 }
 "ne"			{
-	add_deprecated_token(yyextra->deprecated, "ne");
+	add_deprecated_token(yyextra->dfw, "ne");
 	return SIMPLE(TOKEN_TEST_NE);
 }
 ">"		return SIMPLE(TOKEN_TEST_GT);
diff --git a/epan/dfilter/semcheck.c b/epan/dfilter/semcheck.c
index 56662defbf..02bea9194b 100644
--- a/epan/dfilter/semcheck.c
+++ b/epan/dfilter/semcheck.c
@@ -1378,7 +1378,7 @@ check_test(dfwork_t *dfw, stnode_t *st_node)
 				sttype_test_get(st_arg1, &st_arg_op, NULL, NULL);
 				if (st_arg_op == TEST_OP_AND || st_arg_op == TEST_OP_OR) {
 					if (st_op != st_arg_op && !stnode_inside_parens(st_arg1))
-						g_ptr_array_add(dfw->deprecated, g_strdup("suggest parentheses around '&&' within '||'"));
+						add_deprecated_token(dfw, "suggest parentheses around '&&' within '||'");
 				}
 			}
 
@@ -1386,7 +1386,7 @@ check_test(dfwork_t *dfw, stnode_t *st_node)
 				sttype_test_get(st_arg2, &st_arg_op, NULL, NULL);
 				if (st_arg_op == TEST_OP_AND || st_arg_op == TEST_OP_OR) {
 					if (st_op != st_arg_op && !stnode_inside_parens(st_arg2))
-						g_ptr_array_add(dfw->deprecated, g_strdup("suggest parentheses around '&&' within '||'"));
+						add_deprecated_token(dfw, "suggest parentheses around '&&' within '||'");
 				}
 			}