Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit0217a74

Browse files
committed
Fix race condition with BIO methods initialization in libpq with threads
The libpq code in charge of creating per-connection SSL objects wasprone to a race condition when loading the custom BIO methods needed bymy_SSL_set_fd(). As BIO methods are stored as a static variable, theinitialization of a connection could fail because it could be possibleto have one thread refer to my_bio_methods while it is being manipulatedby a second concurrent thread.This error has been introduced by8bb14cd, that has removedssl_config_mutex around the call of my_SSL_set_fd(), that itself setsthe custom BIO methods used in libpq. Like previously, the BIO methodinitialization is now protected by the existing ssl_config_mutex, itselfinitialized earlier for WIN32.While on it, document that my_bio_methods is protected byssl_config_mutex, as this can be easy to miss.Reported-by: Willi MannAuthor: Willi Mann, Michael PaquierDiscussion:https://postgr.es/m/e77abc4c-4d03-4058-a9d7-ef0035657e04@celonis.comBackpatch-through: 12
1 parent450ad65 commit0217a74

File tree

1 file changed

+51
-22
lines changed

1 file changed

+51
-22
lines changed

‎src/interfaces/libpq/fe-secure-openssl.c

Lines changed: 51 additions & 22 deletions
Original file line numberDiff line numberDiff line change
@@ -1496,6 +1496,7 @@ PQsslAttribute(PGconn *conn, const char *attribute_name)
14961496
#defineBIO_set_data(bio,data) (bio->ptr = data)
14971497
#endif
14981498

1499+
/* protected by ssl_config_mutex */
14991500
staticBIO_METHOD*my_bio_methods;
15001501

15011502
staticint
@@ -1561,6 +1562,15 @@ my_sock_write(BIO *h, const char *buf, int size)
15611562
staticBIO_METHOD*
15621563
my_BIO_s_socket(void)
15631564
{
1565+
BIO_METHOD*res;
1566+
1567+
#ifdefENABLE_THREAD_SAFETY
1568+
if (pthread_mutex_lock(&ssl_config_mutex))
1569+
returnNULL;
1570+
#endif
1571+
1572+
res=my_bio_methods;
1573+
15641574
if (!my_bio_methods)
15651575
{
15661576
BIO_METHOD*biom= (BIO_METHOD*)BIO_s_socket();
@@ -1569,39 +1579,58 @@ my_BIO_s_socket(void)
15691579

15701580
my_bio_index=BIO_get_new_index();
15711581
if (my_bio_index==-1)
1572-
returnNULL;
1582+
gotoerr;
15731583
my_bio_index |= (BIO_TYPE_DESCRIPTOR |BIO_TYPE_SOURCE_SINK);
1574-
my_bio_methods=BIO_meth_new(my_bio_index,"libpq socket");
1575-
if (!my_bio_methods)
1576-
returnNULL;
1584+
res=BIO_meth_new(my_bio_index,"libpq socket");
1585+
if (!res)
1586+
gotoerr;
15771587

15781588
/*
15791589
* As of this writing, these functions never fail. But check anyway,
15801590
* like OpenSSL's own examples do.
15811591
*/
1582-
if (!BIO_meth_set_write(my_bio_methods,my_sock_write)||
1583-
!BIO_meth_set_read(my_bio_methods,my_sock_read)||
1584-
!BIO_meth_set_gets(my_bio_methods,BIO_meth_get_gets(biom))||
1585-
!BIO_meth_set_puts(my_bio_methods,BIO_meth_get_puts(biom))||
1586-
!BIO_meth_set_ctrl(my_bio_methods,BIO_meth_get_ctrl(biom))||
1587-
!BIO_meth_set_create(my_bio_methods,BIO_meth_get_create(biom))||
1588-
!BIO_meth_set_destroy(my_bio_methods,BIO_meth_get_destroy(biom))||
1589-
!BIO_meth_set_callback_ctrl(my_bio_methods,BIO_meth_get_callback_ctrl(biom)))
1592+
if (!BIO_meth_set_write(res,my_sock_write)||
1593+
!BIO_meth_set_read(res,my_sock_read)||
1594+
!BIO_meth_set_gets(res,BIO_meth_get_gets(biom))||
1595+
!BIO_meth_set_puts(res,BIO_meth_get_puts(biom))||
1596+
!BIO_meth_set_ctrl(res,BIO_meth_get_ctrl(biom))||
1597+
!BIO_meth_set_create(res,BIO_meth_get_create(biom))||
1598+
!BIO_meth_set_destroy(res,BIO_meth_get_destroy(biom))||
1599+
!BIO_meth_set_callback_ctrl(res,BIO_meth_get_callback_ctrl(biom)))
15901600
{
1591-
BIO_meth_free(my_bio_methods);
1592-
my_bio_methods=NULL;
1593-
returnNULL;
1601+
gotoerr;
15941602
}
15951603
#else
1596-
my_bio_methods=malloc(sizeof(BIO_METHOD));
1597-
if (!my_bio_methods)
1598-
returnNULL;
1599-
memcpy(my_bio_methods,biom,sizeof(BIO_METHOD));
1600-
my_bio_methods->bread=my_sock_read;
1601-
my_bio_methods->bwrite=my_sock_write;
1604+
res=malloc(sizeof(BIO_METHOD));
1605+
if (!res)
1606+
gotoerr;
1607+
memcpy(res,biom,sizeof(BIO_METHOD));
1608+
res->bread=my_sock_read;
1609+
res->bwrite=my_sock_write;
16021610
#endif
16031611
}
1604-
returnmy_bio_methods;
1612+
1613+
my_bio_methods=res;
1614+
1615+
#ifdefENABLE_THREAD_SAFETY
1616+
pthread_mutex_unlock(&ssl_config_mutex);
1617+
#endif
1618+
1619+
returnres;
1620+
1621+
err:
1622+
#ifdefHAVE_BIO_METH_NEW
1623+
if (res)
1624+
BIO_meth_free(res);
1625+
#else
1626+
if (res)
1627+
free(res);
1628+
#endif
1629+
1630+
#ifdefENABLE_THREAD_SAFETY
1631+
pthread_mutex_unlock(&ssl_config_mutex);
1632+
#endif
1633+
returnNULL;
16051634
}
16061635

16071636
/* This should exactly match OpenSSL's SSL_set_fd except for using my BIO */

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp