* [PULL 1/1] json: Fix a memleak in parse_pair()
2020-11-17 14:57 [PULL 0/1] QObject patches patches for 2020-11-17 Markus Armbruster
@ 2020-11-17 14:57 ` Markus Armbruster
2020-11-17 22:06 ` [PULL 0/1] QObject patches patches for 2020-11-17 Peter Maydell
1 sibling, 0 replies; 3+ messages in thread
From: Markus Armbruster @ 2020-11-17 14:57 UTC (permalink / raw)
To: qemu-devel; +Cc: Alex Chen, peter.maydell, Chen Qun, Euler Robot
From: Alex Chen <alex.chen@huawei.com>
In qobject_type(), NULL is returned when the 'QObject' returned from parse_value() is not of QString type,
and this 'QObject' memory will leaked.
So we need to first cache the 'QObject' returned from parse_value(), and finally
free 'QObject' memory at the end of the function.
Also, we add a testcast about invalid dict key.
The memleak stack is as follows:
Direct leak of 32 byte(s) in 1 object(s) allocated from:
#0 0xfffe4b3c34fb in __interceptor_malloc (/lib64/libasan.so.4+0xd34fb)
#1 0xfffe4ae48aa3 in g_malloc (/lib64/libglib-2.0.so.0+0x58aa3)
#2 0xaaab3557d9f7 in qnum_from_int qemu/qobject/qnum.c:25
#3 0xaaab35584d23 in parse_literal qemu/qobject/json-parser.c:511
#4 0xaaab35584d23 in parse_value qemu/qobject/json-parser.c:554
#5 0xaaab35583d77 in parse_pair qemu/qobject/json-parser.c:270
#6 0xaaab355845db in parse_object qemu/qobject/json-parser.c:327
#7 0xaaab355845db in parse_value qemu/qobject/json-parser.c:546
#8 0xaaab35585b1b in json_parser_parse qemu/qobject/json-parser.c:580
#9 0xaaab35583703 in json_message_process_token qemu/qobject/json-streamer.c:92
#10 0xaaab355ddccf in json_lexer_feed_char qemu/qobject/json-lexer.c:313
#11 0xaaab355de0eb in json_lexer_feed qemu/qobject/json-lexer.c:350
#12 0xaaab354aff67 in tcp_chr_read qemu/chardev/char-socket.c:525
#13 0xfffe4ae429db in g_main_context_dispatch (/lib64/libglib-2.0.so.0+0x529db)
#14 0xfffe4ae42d8f (/lib64/libglib-2.0.so.0+0x52d8f)
#15 0xfffe4ae430df in g_main_loop_run (/lib64/libglib-2.0.so.0+0x530df)
#16 0xaaab34d70bff in iothread_run qemu/iothread.c:82
#17 0xaaab3559d71b in qemu_thread_start qemu/util/qemu-thread-posix.c:519
Fixes: 532fb5328473 ("qapi: Make more of qobject_to()")
Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Alex Chen <alex.chen@huawei.com>
Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201113145525.85151-1-alex.chen@huawei.com>
[Commit message tweaked]
---
qobject/json-parser.c | 12 ++++++------
tests/check-qjson.c | 9 +++++++++
2 files changed, 15 insertions(+), 6 deletions(-)
diff --git a/qobject/json-parser.c b/qobject/json-parser.c
index d083810d37..c0f521b56b 100644
--- a/qobject/json-parser.c
+++ b/qobject/json-parser.c
@@ -257,8 +257,9 @@ static JSONToken *parser_context_peek_token(JSONParserContext *ctxt)
*/
static int parse_pair(JSONParserContext *ctxt, QDict *dict)
{
+ QObject *key_obj = NULL;
+ QString *key;
QObject *value;
- QString *key = NULL;
JSONToken *peek, *token;
peek = parser_context_peek_token(ctxt);
@@ -267,7 +268,8 @@ static int parse_pair(JSONParserContext *ctxt, QDict *dict)
goto out;
}
- key = qobject_to(QString, parse_value(ctxt));
+ key_obj = parse_value(ctxt);
+ key = qobject_to(QString, key_obj);
if (!key) {
parse_error(ctxt, peek, "key is not a string in object");
goto out;
@@ -297,13 +299,11 @@ static int parse_pair(JSONParserContext *ctxt, QDict *dict)
qdict_put_obj(dict, qstring_get_str(key), value);
- qobject_unref(key);
-
+ qobject_unref(key_obj);
return 0;
out:
- qobject_unref(key);
-
+ qobject_unref(key_obj);
return -1;
}
diff --git a/tests/check-qjson.c b/tests/check-qjson.c
index 07a773e653..9a02079099 100644
--- a/tests/check-qjson.c
+++ b/tests/check-qjson.c
@@ -1415,6 +1415,14 @@ static void invalid_dict_comma(void)
g_assert(obj == NULL);
}
+static void invalid_dict_key(void)
+{
+ Error *err = NULL;
+ QObject *obj = qobject_from_json("{32:'abc'}", &err);
+ error_free_or_abort(&err);
+ g_assert(obj == NULL);
+}
+
static void unterminated_literal(void)
{
Error *err = NULL;
@@ -1500,6 +1508,7 @@ int main(int argc, char **argv)
g_test_add_func("/errors/unterminated/dict_comma", unterminated_dict_comma);
g_test_add_func("/errors/invalid_array_comma", invalid_array_comma);
g_test_add_func("/errors/invalid_dict_comma", invalid_dict_comma);
+ g_test_add_func("/errors/invalid_dict_key", invalid_dict_key);
g_test_add_func("/errors/unterminated/literal", unterminated_literal);
g_test_add_func("/errors/limits/nesting", limits_nesting);
g_test_add_func("/errors/multiple_values", multiple_values);
--
2.26.2
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