From b81ce7b56616cf9f5dbb790d65111cd5cb7f92d6 Mon Sep 17 00:00:00 2001 From: Anthony Liguori Date: Mon, 5 Mar 2012 17:44:33 -0500 Subject: [PATCH 66/98] json-streamer: limit the maximum recursion depth and maximum token count Signed-off-by: Michael Roth Signed-off-by: Anthony Liguori (cherry picked from commit 29c75ddd87ff7904005da08ff1056395261d90f1) Signed-off-by: Jeff Cody Signed-off-by: Michal Novotny --- json-streamer.c | 17 +++++++++++++++++ 1 files changed, 17 insertions(+), 0 deletions(-) diff --git a/json-streamer.c b/json-streamer.c index 549e9b7..6b9af63 100644 --- a/json-streamer.c +++ b/json-streamer.c @@ -18,6 +18,9 @@ #include "json-lexer.h" #include "json-streamer.h" +#define MAX_TOKEN_SIZE (64ULL << 20) +#define MAX_NESTING (1ULL << 10) + static void json_message_process_token(JSONLexer *lexer, QString *token, JSONTokenType type, int x, int y) { JSONMessageParser *parser = container_of(lexer, JSONMessageParser, lexer); @@ -49,6 +52,8 @@ static void json_message_process_token(JSONLexer *lexer, QString *token, JSONTok qdict_put(dict, "x", qint_from_int(x)); qdict_put(dict, "y", qint_from_int(y)); + parser->token_size += token->length; + qlist_append(parser->tokens, dict); if (parser->brace_count < 0 || @@ -60,6 +65,17 @@ static void json_message_process_token(JSONLexer *lexer, QString *token, JSONTok parser->emit(parser, parser->tokens); QDECREF(parser->tokens); parser->tokens = qlist_new(); + } else if (parser->token_size > MAX_TOKEN_SIZE || + parser->bracket_count > MAX_NESTING || + parser->brace_count > MAX_NESTING) { + /* Security consideration, we limit total memory allocated per object + * and the maximum recursion depth that a message can force. + */ + parser->brace_count = 0; + parser->bracket_count = 0; + parser->emit(parser, parser->tokens); + QDECREF(parser->tokens); + parser->tokens = qlist_new(); } } @@ -70,6 +86,7 @@ void json_message_parser_init(JSONMessageParser *parser, parser->brace_count = 0; parser->bracket_count = 0; parser->tokens = qlist_new(); + parser->token_size = 0; json_lexer_init(&parser->lexer, json_message_process_token); } -- 1.7.7.6