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

Commit01eca6a

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 parentbc3c8db commit01eca6a

File tree

1 file changed

+42
-22
lines changed

1 file changed

+42
-22
lines changed

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

Lines changed: 42 additions & 22 deletions
Original file line numberDiff line numberDiff line change
@@ -1820,6 +1820,7 @@ PQsslAttribute(PGconn *conn, const char *attribute_name)
18201820
#defineBIO_set_data(bio,data) (bio->ptr = data)
18211821
#endif
18221822

1823+
/* protected by ssl_config_mutex */
18231824
staticBIO_METHOD*my_bio_methods;
18241825

18251826
staticint
@@ -1885,6 +1886,13 @@ my_sock_write(BIO *h, const char *buf, int size)
18851886
staticBIO_METHOD*
18861887
my_BIO_s_socket(void)
18871888
{
1889+
BIO_METHOD*res;
1890+
1891+
if (pthread_mutex_lock(&ssl_config_mutex))
1892+
returnNULL;
1893+
1894+
res=my_bio_methods;
1895+
18881896
if (!my_bio_methods)
18891897
{
18901898
BIO_METHOD*biom= (BIO_METHOD*)BIO_s_socket();
@@ -1893,39 +1901,51 @@ my_BIO_s_socket(void)
18931901

18941902
my_bio_index=BIO_get_new_index();
18951903
if (my_bio_index==-1)
1896-
returnNULL;
1904+
gotoerr;
18971905
my_bio_index |= (BIO_TYPE_DESCRIPTOR |BIO_TYPE_SOURCE_SINK);
1898-
my_bio_methods=BIO_meth_new(my_bio_index,"libpq socket");
1899-
if (!my_bio_methods)
1900-
returnNULL;
1906+
res=BIO_meth_new(my_bio_index,"libpq socket");
1907+
if (!res)
1908+
gotoerr;
19011909

19021910
/*
19031911
* As of this writing, these functions never fail. But check anyway,
19041912
* like OpenSSL's own examples do.
19051913
*/
1906-
if (!BIO_meth_set_write(my_bio_methods,my_sock_write)||
1907-
!BIO_meth_set_read(my_bio_methods,my_sock_read)||
1908-
!BIO_meth_set_gets(my_bio_methods,BIO_meth_get_gets(biom))||
1909-
!BIO_meth_set_puts(my_bio_methods,BIO_meth_get_puts(biom))||
1910-
!BIO_meth_set_ctrl(my_bio_methods,BIO_meth_get_ctrl(biom))||
1911-
!BIO_meth_set_create(my_bio_methods,BIO_meth_get_create(biom))||
1912-
!BIO_meth_set_destroy(my_bio_methods,BIO_meth_get_destroy(biom))||
1913-
!BIO_meth_set_callback_ctrl(my_bio_methods,BIO_meth_get_callback_ctrl(biom)))
1914+
if (!BIO_meth_set_write(res,my_sock_write)||
1915+
!BIO_meth_set_read(res,my_sock_read)||
1916+
!BIO_meth_set_gets(res,BIO_meth_get_gets(biom))||
1917+
!BIO_meth_set_puts(res,BIO_meth_get_puts(biom))||
1918+
!BIO_meth_set_ctrl(res,BIO_meth_get_ctrl(biom))||
1919+
!BIO_meth_set_create(res,BIO_meth_get_create(biom))||
1920+
!BIO_meth_set_destroy(res,BIO_meth_get_destroy(biom))||
1921+
!BIO_meth_set_callback_ctrl(res,BIO_meth_get_callback_ctrl(biom)))
19141922
{
1915-
BIO_meth_free(my_bio_methods);
1916-
my_bio_methods=NULL;
1917-
returnNULL;
1923+
gotoerr;
19181924
}
19191925
#else
1920-
my_bio_methods=malloc(sizeof(BIO_METHOD));
1921-
if (!my_bio_methods)
1922-
returnNULL;
1923-
memcpy(my_bio_methods,biom,sizeof(BIO_METHOD));
1924-
my_bio_methods->bread=my_sock_read;
1925-
my_bio_methods->bwrite=my_sock_write;
1926+
res=malloc(sizeof(BIO_METHOD));
1927+
if (!res)
1928+
gotoerr;
1929+
memcpy(res,biom,sizeof(BIO_METHOD));
1930+
res->bread=my_sock_read;
1931+
res->bwrite=my_sock_write;
19261932
#endif
19271933
}
1928-
returnmy_bio_methods;
1934+
1935+
my_bio_methods=res;
1936+
pthread_mutex_unlock(&ssl_config_mutex);
1937+
returnres;
1938+
1939+
err:
1940+
#ifdefHAVE_BIO_METH_NEW
1941+
if (res)
1942+
BIO_meth_free(res);
1943+
#else
1944+
if (res)
1945+
free(res);
1946+
#endif
1947+
pthread_mutex_unlock(&ssl_config_mutex);
1948+
returnNULL;
19291949
}
19301950

19311951
/* 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