https://bugs.openldap.org/show_bug.cgi?id=10330

Issue ID: 10330 Summary: TIMEOUT and NETWORK_TIMEOUT not respected when receiving bad data during TLS negotiation Product: OpenLDAP Version: 2.6.9 Hardware: x86_64 OS: Linux Status: UNCONFIRMED Keywords: needs_review Severity: normal Priority: --- Component: libraries Assignee: bugs@openldap.org Reporter: michael.kourlas@solace.com Target Milestone: ---

Created attachment 1063 --> https://bugs.openldap.org/attachment.cgi?id=1063&action=edit Test program

This seems related to bug 8047.

Steps to reproduce:

1. Setup a netcat server on a host: "nc -l -k -p 636".

2. On a different host, attempt to connect to the host running "nc" as if it were an LDAP server via ldaps: "ldapsearch -o NETWORK_TIMEOUT=5 -o TIMEOUT=5 -H ldaps://<ip>:636".

3. During the 5 second timeout period, switch back to the netcat server and transmit a newline by pressing enter.

4. ldapsearch will hang forever until the TCP connection is closed (e.g. by killing the netcat server).

My expectation would be that ldapsearch would exit after 5 seconds, per the NETWORK_TIMEOUT and TIMEOUT options.

I'm using the following version of ldapsearch on Fedora 41 (x86-64):

ldapsearch: @(#) $OpenLDAP: ldapsearch 2.6.9 (Mar 27 2025 00:00:00) $ openldap (LDAP library: OpenLDAP 20609)

This problem is also observable when directly using the OpenLDAP C API. This is more of an issue, since any application using the API could become unresponsive if these timeout values aren't respected.

I've attached a short test program which can be used instead of ldapsearch. If I abort the test program while it is stuck in this state, the traceback looks like this:

#0 0x00007f50b7a25811 in __GI___libc_read (fd=3, buf=0x2aaf9ac5, nbytes=3) at ../sysdeps/unix/sysv/linux/read.c:26 #1 0x00007f50b792f8b9 in sb_debug_read (sbiod=0x2aadf390, buf=0x2aaf9ac5, len=3) at /usr/src/debug/openldap-2.6.9-1.fc41.x86_64/openldap-2.6.9/libraries/liblber/sockbuf.c:829 #2 0x00007f50b7b61156 in tlso_bio_read (b=0x2aadf9c0, buf=0x2aaf9ac5 "", len=3) at /usr/src/debug/openldap-2.6.9-1.fc41.x86_64/openldap-2.6.9/libraries/libldap/tls_o.c:1279 #3 0x00007f50b7221ea3 in bread_conv (bio=<optimized out>, data=<optimized out>, datal=<optimized out>, readbytes=0x7ffd1cf2e3f0) at crypto/bio/bio_meth.c:121 #4 0x00007f50b7226047 in bio_read_intern (b=b@entry=0x2aadf9c0, data=0x2aaf9ac5, data@entry=0x555f3588, dlen=3, dlen@entry=18446744072487067717, readbytes=readbytes@entry=0x7ffd1cf2e3f0) at crypto/bio/bio_lib.c:285 #5 0x00007f50b72261db in BIO_read (b=0x2aadf9c0, data=0x555f3588, dlen=-1222483899) at crypto/bio/bio_lib.c:311 #6 BIO_read (b=b@entry=0x2aadf9c0, data=data@entry=0x2aaf9ac5, dlen=dlen@entry=3) at crypto/bio/bio_lib.c:303 #7 0x00007f50b783ce03 in tls_default_read_n (rl=0x2aaec1c0, n=5, max=<optimized out>, extend=<optimized out>, clearold=<optimized out>, readbytes=0x7ffd1cf2e4b8) at ssl/record/methods/tls_common.c:406 #8 0x00007f50b784151b in tls_get_more_records (rl=0x2aaec1c0) at ssl/record/methods/tls_common.c:583 #9 0x00007f50b783b8ea in tls_read_record (rl=0x2aaec1c0, rechandle=0x2aaeb600, rversion=0x2aaeb608, type=0x2aaeb60c "", data=0x2aaeb610, datalen=0x2aaeb620, epoch=0x0, seq_num=0x0) at ssl/record/methods/tls_common.c:1130 #10 0x00007f50b783969a in ssl3_read_bytes (ssl=<optimized out>, type=22 '\026', recvd_type=0x7ffd1cf2e684 "", buf=0x2aaee480 "\001", len=4, peek=0, readbytes=0x7ffd1cf2e688) at ssl/record/rec_layer_s3.c:689 #11 0x00007f50b784f5a7 in tls_get_message_header (s=0x2aaea980, mt=<synthetic pointer>) at ssl/statem/statem_lib.c:1554 --Type <RET> for more, q to quit, c to continue without paging-- #12 read_state_machine (s=0x2aaea980) at ssl/statem/statem.c:625 #13 state_machine (s=<optimized out>, server=0) at ssl/statem/statem.c:479 #14 0x00007f50b7b615c3 in tlso_session_connect (ld=<optimized out>, sess=0x2aaea980, name_in=<optimized out>) at /usr/src/debug/openldap-2.6.9-1.fc41.x86_64/openldap-2.6.9/libraries/libldap/tls_o.c:693 #15 0x00007f50b7b65bf2 in ldap_int_tls_connect (ld=ld@entry=0x2a9b2430, conn=conn@entry=0x2a9b25d0, host=host@entry=0x2a9b2550 "192.168.133.56") at /usr/src/debug/openldap-2.6.9-1.fc41.x86_64/openldap-2.6.9/libraries/libldap/tls2.c:425 #16 0x00007f50b7b6636f in ldap_int_tls_start (ld=0x2a9b2430, conn=0x2a9b25d0, srv=<optimized out>) at /usr/src/debug/openldap-2.6.9-1.fc41.x86_64/openldap-2.6.9/libraries/libldap/tls2.c:1245 #17 0x00007f50b7b3d4c2 in ldap_int_open_connection (ld=0x2a9b2430, conn=0x2a9b25d0, srv=0x2a9b24d0, async=0) at /usr/src/debug/openldap-2.6.9-1.fc41.x86_64/openldap-2.6.9/libraries/libldap/open.c:515 #18 0x00007f50b7b5212d in ldap_new_connection (ld=0x2a9b2430, srvlist=0x2a9b2878, use_ldsb=1, connect=<optimized out>, bind=0x0, m_req=0, m_res=0) at /usr/src/debug/openldap-2.6.9-1.fc41.x86_64/openldap-2.6.9/libraries/libldap/request.c:491 #19 0x00007f50b7b3c7b4 in ldap_open_defconn (ld=0x2a9b2430) at /usr/src/debug/openldap-2.6.9-1.fc41.x86_64/openldap-2.6.9/libraries/libldap/open.c:42 #20 0x00007f50b7b52ed8 in ldap_send_initial_request (ld=0x2a9b2430, msgtype=96, dn=0x4023a9 "cn=admin,dc=solace,dc=com", ber=0x2a9b2570, msgid=1) at /usr/src/debug/openldap-2.6.9-1.fc41.x86_64/openldap-2.6.9/libraries/libldap/request.c:131 #21 0x00007f50b7b429b9 in ldap_sasl_bind (ld=0x2a9b2430, dn=0x4023a9 "cn=admin,dc=solace,dc=com", mechanism=0x0, cred=0x7ffd1cf2eb90, sctrls=0x0, cctrls=0x0, msgidp=0x7ffd1cf2eb8c) at /usr/src/debug/openldap-2.6.9-1.fc41.x86_64/openldap-2.6.9/libraries/libldap/sasl.c:164