dhawes@vt.edu wrote:
dhawes@vt.edu wrote:
Full_Name: David Hawes Version: 2.4.13 OS: Debian GNU/Linux 4.0 URL: Submission from: (NULL) (98.117.88.57)
As outlined at:
http://www.openldap.org/lists/openldap-software/200811/msg00136.html
OpenLDAP 2.4 leaks memory when TLS client certificates are used. Running slapd under valgrind yields the following:
==13311== 4,906 (92 direct, 4,814 indirect) bytes in 1 blocks are definitely lost in loss record 19 of 23 ==13311== at 0x401D898: malloc (vg_replace_malloc.c:207) ==13311== by 0x41FCCC4: default_malloc_ex (mem.c:79) ==13311== by 0x41FD33F: CRYPTO_malloc (mem.c:304) ==13311== by 0x428CA65: asn1_item_ex_combine_new (tasn_new.c:191) ==13311== by 0x428C79C: ASN1_item_ex_new (tasn_new.c:85) ==13311== by 0x428ECAA: ASN1_item_ex_d2i (tasn_dec.c:399) ==13311== by 0x428E5F9: ASN1_item_d2i (tasn_dec.c:134) ==13311== by 0x4286A57: d2i_X509 (x_x509.c:136) ==13311== by 0x4194F26: ssl3_get_client_certificate (s3_srvr.c:2521) ==13311== by 0x4191897: ssl3_accept (s3_srvr.c:462) ==13311== by 0x41AD930: SSL_accept (ssl_lib.c:867) ==13311== by 0x815D00E: ldap_pvt_tls_accept (tls.c:1594) ==13311== by 0x8076926: connection_read_thread (connection.c:1286) ==13311== by 0x813CEE5: ldap_int_thread_pool_wrapper (tpool.c:663) ==13311== by 0x415823F: start_thread (in /lib/tls/i686/cmov/libpthread-2.3.6.so) ==13311== by 0x43ED49D: clone (in /lib/tls/i686/cmov/libc-2.3.6.so)
Philip Guenther notes:
In 2.4.x, tls_get_cert_dn() leaks a reference to the client's X509 cert: the call to SSL_get_peer_certificate() in tls_get_cert() increments the reference count on the cert and it never gets decremented by a call to X509_free(). Simply adding the call there might not be safe, depending on whether the berval that tls_get_cert_dn() sets up relies on the underlying X509 to stay valid for longer than this chain of calls, as the X509 may be invalidated by a rehandshake.
Calling X509_free(x) before the return statement in tls_get_cert_dn() does fix the memory leak, though I do not know if this is proper, as Philip noted.
My apologies for not checking the ITS before sending that message.
The fix in HEAD works.