Please find attached a test program and Makefile plus a test script to drive it. Basically the program exercises concurrent SASL binds.
With the current packages in xenial, the test program fails in a variety of ways: $ ./sasltest rc = -6 (Unknown authentication method) sasltest: sasltest.c:70: bind_thread: Assertion `rc == LDAP_SUCCESS' failed. Aborted $ ./sasltest Segmentation fault $ ./sasltest Bus error or even simply hanging/spinning. (If you execute ./sasltest in a shell, be sure to export LDAPSASL_SECPROPS=none first to avoid the confidentiality requirement.) With the proposed patch, the test program should reliably complete all its iterations (takes a few seconds) and exit successfully. I hope this reproduces the problem for you. My proposed debdiff and PPA are out of date and should be rebased using the actual upstream patches. (Similar changes already landed in Debian stretch.) I will try to take care of that this week, but if you have everything you need and the tuits, feel free to proceed without me. ** Attachment added: "Makefile" https://bugs.launchpad.net/bugs/1688575/+attachment/5139678/+files/Makefile ** Attachment added: "sasltest.c" https://bugs.launchpad.net/bugs/1688575/+attachment/5139679/+files/sasltest.c ** Attachment added: "testscript" https://bugs.launchpad.net/bugs/1688575/+attachment/5139680/+files/testscript -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openldap in Ubuntu. https://bugs.launchpad.net/bugs/1688575 Title: Segmentation fault on a slave slapd (sync replication with kerberos authentication) Status in openldap: Fix Released Status in openldap package in Ubuntu: Fix Released Bug description: I have a slapd problem on a freshly installed 16.04 machine: slapd[17107]: segfault at 1a ip 00007f3c12c79f55 sp 00007f3c03c2d080 error 4 in libsasl2.so.2.0.25[7f3c12c72000+19000] I'm using the server as Slave LDAP-Server and sync replication with kerberos authentication. The service either starts and runs successfully or it fails with segmentation fault or 100% CPU. Maybe an useful info, I'm replicating two databases. When I deactivate syncrepl for one of them (doesn't matter which one) the problem is not occuring. Linux xxx 4.4.0-75-generic #96-Ubuntu SMP Thu Apr 20 09:56:33 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux slapd 2.4.42+dfsg-2ubuntu3.1 libsasl2-2:amd64 2.1.26.dfsg1-14build1 libsasl2-modules:amd64 2.1.26.dfsg1-14build1 libsasl2-modules-gssapi-mit:amd64 2.1.26.dfsg1-14build1 GDB debug: Starting program: /usr/sbin/slapd -h "ldap:/// ldaps:/// ldapi:///" -u openldap -g openldap -f /etc/ldap/slapd.conf -d 256 [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". 590c82ab @(#) $OpenLDAP: slapd (Ubuntu) (May 11 2016 16:12:05) $ buildd@lgw01-10:/build/openldap-mF7Kfq/openldap-2.4.42+dfsg/debian/build/servers/slapd 590c82ab slapd starting [New Thread 0x7f2e96b7b700 (LWP 42139)] [New Thread 0x7f2e9637a700 (LWP 42140)] [New Thread 0x7f2e95b79700 (LWP 42141)] [New Thread 0x7f2e95378700 (LWP 42142)] [New Thread 0x7f2e94b77700 (LWP 42143)] 590c82ba slap_client_connect: URI=ldap://xxx ldap_sasl_interactive_bind_s failed (-6) 590c82ba do_syncrepl: rid=132 rc -6 retrying (9 retries left) Thread 4 "slapd" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7f2e95b79700 (LWP 42141)] 0x00007f2ea53035b5 in sasl_client_add_plugin () from /usr/lib/x86_64-linux-gnu/libsasl2.so.2 (gdb) thr apply all bt Thread 6 (Thread 0x7f2e94b77700 (LWP 42143)): #0 pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007f2ea59463f3 in ?? () from /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2 #2 0x00007f2ea487c6ba in start_thread (arg=0x7f2e94b77700) at pthread_create.c:333 #3 0x00007f2ea45b282d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 Thread 5 (Thread 0x7f2e95378700 (LWP 42142)): #0 pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007f2ea59463f3 in ?? () from /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2 #2 0x00007f2ea487c6ba in start_thread (arg=0x7f2e95378700) at pthread_create.c:333 #3 0x00007f2ea45b282d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 Thread 4 (Thread 0x7f2e95b79700 (LWP 42141)): #0 0x00007f2ea53035b5 in sasl_client_add_plugin () from /usr/lib/x86_64-linux-gnu/libsasl2.so.2 #1 0x00007f2ea530f250 in ?? () from /usr/lib/x86_64-linux-gnu/libsasl2.so.2 #2 0x00007f2ea5303d69 in sasl_client_init () from /usr/lib/x86_64-linux-gnu/libsasl2.so.2 #3 0x00007f2ea594da6c in ldap_int_sasl_init () from /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2 #4 0x00007f2ea594db2c in ldap_int_sasl_open () from /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2 #5 0x00007f2ea594e2d4 in ldap_int_sasl_bind () from /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2 #6 0x00007f2ea5951828 in ldap_sasl_interactive_bind () from /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2 #7 0x00007f2ea5951a4e in ldap_sasl_interactive_bind_s () from /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2 #8 0x0000561fbc556db4 in slap_client_connect (ldp=0x561fbe1e9f68, sb=0x561fbe1e9d40) at ../../../../servers/slapd/config.c:2063 #9 0x0000561fbc5c699d in do_syncrep1 (si=0x561fbe1e9d10, op=0x7f2e95b787b0) at ../../../../servers/slapd/syncrepl.c:618 #10 do_syncrepl (ctx=<optimized out>, arg=0x561fbe1e5620) at ../../../../servers/slapd/syncrepl.c:1548 #11 0x00007f2ea59463a2 in ?? () from /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2 #12 0x00007f2ea487c6ba in start_thread (arg=0x7f2e95b79700) at pthread_create.c:333 #13 0x00007f2ea45b282d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 Thread 3 (Thread 0x7f2e9637a700 (LWP 42140)): ---Type <return> to continue, or q <return> to quit--- #0 pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007f2ea59463f3 in ?? () from /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2 #2 0x00007f2ea487c6ba in start_thread (arg=0x7f2e9637a700) at pthread_create.c:333 #3 0x00007f2ea45b282d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 Thread 2 (Thread 0x7f2e96b7b700 (LWP 42139)): #0 0x00007f2ea45b2e23 in epoll_wait () at ../sysdeps/unix/syscall-template.S:84 #1 0x0000561fbc55a8f0 in slapd_daemon_task (ptr=<optimized out>) at ../../../../servers/slapd/daemon.c:2539 #2 0x00007f2ea487c6ba in start_thread (arg=0x7f2e96b7b700) at pthread_create.c:333 #3 0x00007f2ea45b282d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 Thread 1 (Thread 0x7f2ea5d96740 (LWP 42138)): #0 0x00007f2ea487d98d in pthread_join (threadid=139838073845504, thread_return=0x0) at pthread_join.c:90 #1 0x0000561fbc55cc81 in slapd_daemon () at ../../../../servers/slapd/daemon.c:2932 #2 0x0000561fbc543bea in main (argc=11, argv=<optimized out>) at ../../../../servers/slapd/main.c:1017 (gdb) To manage notifications about this bug go to: https://bugs.launchpad.net/openldap/+bug/1688575/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
