Fix talloc memory heirarchy bug. If there's an SMB2 sessionsetup in flight when we...

Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Mon Sep 10 23:34:06 CEST 2012 on sn-devel-104

diff --git a/source3/smbd/smb2_sesssetup.c b/source3/smbd/smb2_sesssetup.c
index a03abf73aa77dda803c8083dc5cc25d0aa7d396a..61b5519d979dc2702ddfcce1356eb05f7e31f8e1 100644 (file)
--- a/source3/smbd/smb2_sesssetup.c
+++ b/source3/smbd/smb2_sesssetup.c
@@ -439,8 +439,16 @@ struct smbd_smb2_session_setup_state {
        uint16_t out_session_flags;
        DATA_BLOB out_security_buffer;
        uint64_t out_session_id;
+       /* The following pointer is owned by state->session. */
+       struct smbd_smb2_session_setup_state **pp_self_ref;
 };
 
+static int pp_self_ref_destructor(struct smbd_smb2_session_setup_state **pp_state)
+{
+       (*pp_state)->session = NULL;
+       return 0;
+}
+
 static int smbd_smb2_session_setup_state_destructor(struct smbd_smb2_session_setup_state *state)
 {
        /*
@@ -454,6 +462,24 @@ static int smbd_smb2_session_setup_state_destructor(struct smbd_smb2_session_set
 static void smbd_smb2_session_setup_gensec_done(struct tevent_req *subreq);
 static void smbd_smb2_session_setup_previous_done(struct tevent_req *subreq);
 
+/************************************************************************
+ We have to tag the state->session pointer with memory talloc'ed
+ on it to ensure it gets NULL'ed out if the underlying struct smbXsrv_session
+ is deleted by shutdown whilst this request is in flight.
+************************************************************************/
+
+static NTSTATUS tag_state_session_ptr(struct smbd_smb2_session_setup_state *state)
+{
+       state->pp_self_ref = talloc_zero(state->session,
+                       struct smbd_smb2_session_setup_state *);
+       if (state->pp_self_ref == NULL) {
+               return NT_STATUS_NO_MEMORY;
+       }
+       *state->pp_self_ref = state;
+       talloc_set_destructor(state->pp_self_ref, pp_self_ref_destructor);
+       return NT_STATUS_OK;
+}
+
 static struct tevent_req *smbd_smb2_session_setup_send(TALLOC_CTX *mem_ctx,
                                        struct tevent_context *ev,
                                        struct smbd_smb2_request *smb2req,
@@ -522,6 +548,11 @@ static struct tevent_req *smbd_smb2_session_setup_send(TALLOC_CTX *mem_ctx,
                }
        }
 
+       status = tag_state_session_ptr(state);
+       if (tevent_req_nterror(req, status)) {
+               return tevent_req_post(req, ev);
+       }
+
        if (state->session->gensec == NULL) {
                status = auth_generic_prepare(state->session,
                                              state->session->connection->remote_address,
@@ -577,7 +608,7 @@ static void smbd_smb2_session_setup_gensec_done(struct tevent_req *subreq)
        if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
                state->out_session_id = state->session->global->session_wire_id;
                /* we want to keep the session */
-               state->session = NULL;
+               TALLOC_FREE(state->pp_self_ref);
                tevent_req_nterror(req, status);
                return;
        }
@@ -617,7 +648,7 @@ static void smbd_smb2_session_setup_gensec_done(struct tevent_req *subreq)
                        return;
                }
                /* we want to keep the session */
-               state->session = NULL;
+               TALLOC_FREE(state->pp_self_ref);
                tevent_req_done(req);
                return;
        }
@@ -633,7 +664,7 @@ static void smbd_smb2_session_setup_gensec_done(struct tevent_req *subreq)
        }
 
        /* we want to keep the session */
-       state->session = NULL;
+       TALLOC_FREE(state->pp_self_ref);
        tevent_req_done(req);
        return;
 }
@@ -664,7 +695,7 @@ static void smbd_smb2_session_setup_previous_done(struct tevent_req *subreq)
                        return;
                }
                /* we want to keep the session */
-               state->session = NULL;
+               TALLOC_FREE(state->pp_self_ref);
                tevent_req_done(req);
                return;
        }
@@ -680,7 +711,7 @@ static void smbd_smb2_session_setup_previous_done(struct tevent_req *subreq)
        }
 
        /* we want to keep the session */
-       state->session = NULL;
+       TALLOC_FREE(state->pp_self_ref);
        tevent_req_done(req);
        return;
 }