The array of sasl_callback_t callbacks which is passed to sasl_client_new() must be kept alive as long as the created sasl_conn_t object is alive as cyrus-sasl uses this structure internally for things like logging, so the memory used for callbacks must only be freed after sasl_dispose() has been called. During testing of successful SASL logins with virsh -c qemu+tls:///system list --all I've been getting invalid read reports from valgrind ==9237== Invalid read of size 8 ==9237== at 0x6E93B6F: _sasl_getcallback (common.c:1745) ==9237== by 0x6E95430: _sasl_log (common.c:1850) ==9237== by 0x16593D87: digestmd5_client_mech_dispose (digestmd5.c:4580) ==9237== by 0x6E91653: client_dispose (client.c:332) ==9237== by 0x6E9476A: sasl_dispose (common.c:851) ==9237== by 0x4E225A1: virNetSASLSessionDispose (virnetsaslcontext.c:678) ==9237== by 0x4CBC551: virObjectUnref (virobject.c:262) ==9237== by 0x4E254D1: virNetSocketDispose (virnetsocket.c:1042) ==9237== by 0x4CBC551: virObjectUnref (virobject.c:262) ==9237== by 0x4E2701C: virNetSocketEventFree (virnetsocket.c:1794) ==9237== by 0x4C965D3: virEventPollCleanupHandles (vireventpoll.c:583) ==9237== by 0x4C96987: virEventPollRunOnce (vireventpoll.c:652) ==9237== by 0x4C94730: virEventRunDefaultImpl (virevent.c:274) ==9237== by 0x12C7BA: vshEventLoop (virsh.c:2407) ==9237== by 0x4CD3D04: virThreadHelper (virthreadpthread.c:161) ==9237== by 0x7DAEF32: start_thread (pthread_create.c:309) ==9237== by 0x8C86EAC: clone (clone.S:111) ==9237== Address 0xe2d61b0 is 0 bytes inside a block of size 168 free'd ==9237== at 0x4A07577: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so) ==9237== by 0x4C73827: virFree (viralloc.c:580) ==9237== by 0x4DE4BC7: remoteAuthSASL (remote_driver.c:4219) ==9237== by 0x4DE33D0: remoteAuthenticate (remote_driver.c:3639) ==9237== by 0x4DDBFAA: doRemoteOpen (remote_driver.c:832) ==9237== by 0x4DDC8DC: remoteConnectOpen (remote_driver.c:1031) ==9237== by 0x4D8595F: do_open (libvirt.c:1239) ==9237== by 0x4D863F3: virConnectOpenAuth (libvirt.c:1481) ==9237== by 0x12762B: vshReconnect (virsh.c:337) ==9237== by 0x12C9B0: vshInit (virsh.c:2470) ==9237== by 0x12E9A5: main (virsh.c:3338) This commit changes virNetSASLSessionNewClient() to take ownership of the SASL callbacks. Then we can free them in virNetSASLSessionDispose() after the corresponding sasl_conn_t has been freed. --- src/remote/remote_driver.c | 2 ++ src/rpc/virnetsaslcontext.c | 6 ++++-- src/rpc/virnetsaslcontext.h | 2 +- 3 files changed, 7 insertions(+), 3 deletions(-) diff --git a/src/remote/remote_driver.c b/src/remote/remote_driver.c index 5c559ee..3a22cdf 100644 --- a/src/remote/remote_driver.c +++ b/src/remote/remote_driver.c @@ -4033,6 +4033,8 @@ remoteAuthSASL(virConnectPtr conn, struct private_data *priv, virNetClientRemoteAddrString(priv->client), saslcb))) goto cleanup; + /* saslcb is now owned by sasl */ + saslcb = NULL; # ifdef WITH_GNUTLS /* Initialize some connection props we care about */ diff --git a/src/rpc/virnetsaslcontext.c b/src/rpc/virnetsaslcontext.c index 35dc6cf..1baf41e 100644 --- a/src/rpc/virnetsaslcontext.c +++ b/src/rpc/virnetsaslcontext.c @@ -44,6 +44,7 @@ struct _virNetSASLSession { sasl_conn_t *conn; size_t maxbufsize; + sasl_callback_t *callbacks; }; @@ -167,7 +168,7 @@ virNetSASLSessionPtr virNetSASLSessionNewClient(virNetSASLContextPtr ctxt ATTRIB const char *hostname, const char *localAddr, const char *remoteAddr, - const sasl_callback_t *cbs) + sasl_callback_t *cbs) { virNetSASLSessionPtr sasl = NULL; int err; @@ -191,6 +192,7 @@ virNetSASLSessionPtr virNetSASLSessionNewClient(virNetSASLContextPtr ctxt ATTRIB err, sasl_errstring(err, NULL, NULL)); goto cleanup; } + sasl->callbacks = cbs; return sasl; @@ -674,5 +676,5 @@ void virNetSASLSessionDispose(void *obj) if (sasl->conn) sasl_dispose(&sasl->conn); - + VIR_FREE(sasl->callbacks); } diff --git a/src/rpc/virnetsaslcontext.h b/src/rpc/virnetsaslcontext.h index e726302..54634d5 100644 --- a/src/rpc/virnetsaslcontext.h +++ b/src/rpc/virnetsaslcontext.h @@ -49,7 +49,7 @@ virNetSASLSessionPtr virNetSASLSessionNewClient(virNetSASLContextPtr ctxt, const char *hostname, const char *localAddr, const char *remoteAddr, - const sasl_callback_t *cbs); + sasl_callback_t *cbs); virNetSASLSessionPtr virNetSASLSessionNewServer(virNetSASLContextPtr ctxt, const char *service, const char *localAddr, -- 1.8.4.2 -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list