From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Thu, 28 May 2020 09:49:33 +0000 (+0300)
Subject: lib-mail: message-parser - Fix assert-crash if parsing is stopped early
X-Git-Tag: 2.3.11.2~32
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b38875a48acec9c91fb23576f78b2297e0d92a22;p=thirdparty%2Fdovecot%2Fcore.git

lib-mail: message-parser - Fix assert-crash if parsing is stopped early

Some callers don't want to parse the full message.

Fixes:
Panic: file message-parser.c: line 793 (message_parser_deinit_from_parts): assertion failed: (ctx->nested_parts_count == 0)
---

diff --git a/src/lib-mail/message-parser.c b/src/lib-mail/message-parser.c
index 5e74fb7b5b..6370a1bff7 100644
--- a/src/lib-mail/message-parser.c
+++ b/src/lib-mail/message-parser.c
@@ -787,7 +787,9 @@ int message_parser_deinit_from_parts(struct message_parser_ctx **_ctx,
 	if (ctx->hdr_parser_ctx != NULL)
 		message_parse_header_deinit(&ctx->hdr_parser_ctx);
 	boundary_remove_until(ctx, NULL);
-	i_assert(ctx->nested_parts_count == 0);
+	/* caller might have stopped the parsing early */
+	i_assert(ctx->nested_parts_count == 0 ||
+		 i_stream_have_bytes_left(ctx->input));
 
 	i_stream_unref(&ctx->input);
 	array_free(&ctx->next_part_stack);
diff --git a/src/lib-mail/test-message-parser.c b/src/lib-mail/test-message-parser.c
index 33ce79462b..1b782f5df2 100644
--- a/src/lib-mail/test-message-parser.c
+++ b/src/lib-mail/test-message-parser.c
@@ -175,6 +175,36 @@ static void test_message_parser_small_blocks(void)
 	test_end();
 }
 
+static void test_message_parser_stop_early(void)
+{
+	struct message_parser_ctx *parser;
+	struct istream *input;
+	struct message_part *parts;
+	struct message_block block;
+	unsigned int i;
+	pool_t pool;
+	int ret;
+
+	test_begin("message parser stop early");
+	pool = pool_alloconly_create("message parser", 10240);
+	input = test_istream_create(test_msg);
+
+	test_istream_set_allow_eof(input, FALSE);
+	for (i = 1; i <= TEST_MSG_LEN+1; i++) {
+		i_stream_seek(input, 0);
+		test_istream_set_size(input, i);
+		parser = message_parser_init(pool, input, &set_empty);
+		while ((ret = message_parser_parse_next_block(parser,
+							      &block)) > 0) ;
+		test_assert(ret == 0);
+		message_parser_deinit(&parser, &parts);
+	}
+
+	i_stream_unref(&input);
+	pool_unref(&pool);
+	test_end();
+}
+
 static void test_message_parser_truncated_mime_headers(void)
 {
 static const char input_msg[] =
@@ -1058,6 +1088,7 @@ int main(void)
 {
 	static void (*const test_functions[])(void) = {
 		test_message_parser_small_blocks,
+		test_message_parser_stop_early,
 		test_message_parser_truncated_mime_headers,
 		test_message_parser_truncated_mime_headers2,
 		test_message_parser_truncated_mime_headers3,