Fixed up mutex protection around winbindd logon code. Sync with APP-HEAD.

Jeremy.
(This used to be commit 3d04872499332ef2d8e7479b924afc8fc1ac29d7)

diff --git a/source3/include/local.h b/source3/include/local.h
index 20fa5ff52a4ed83a72e3c8d2991c51a46c9acb94..bf828b5894e4f73e80bc9667e58374a8caf9db05 100644 (file)
--- a/source3/include/local.h
+++ b/source3/include/local.h
@@ -216,4 +216,12 @@
 /* Max number of open RPC pipes. */
 #define MAX_OPEN_PIPES 2048
 
+/* Tuning for server auth mutex. */
+#define CLI_AUTH_TIMEOUT 5000 /* In milli-seconds. */
+#define NUM_CLI_AUTH_CONNECT_RETRIES 3
+/* Number in seconds to wait for the mutex. This must be less than 30 seconds. */
+#define SERVER_MUTEX_WAIT_TIME ( ((NUM_CLI_AUTH_CONNECT_RETRIES) * ((CLI_AUTH_TIMEOUT)/1000)) + 5)
+/* Number in seconds for winbindd to wait for the mutex. Make this 2 * smbd wait time. */
+#define WINBIND_SERVER_MUTEX_WAIT_TIME (( ((NUM_CLI_AUTH_CONNECT_RETRIES) * ((CLI_AUTH_TIMEOUT)/1000)) + 5)*2)
+
 #endif

diff --git a/source3/lib/server_mutex.c b/source3/lib/server_mutex.c
index 3e5512c734205d77720525cab9dc89af7af0972a..878e5497d8e86df3d6edec44d65043dc6d52c4e7 100644 (file)
--- a/source3/lib/server_mutex.c
+++ b/source3/lib/server_mutex.c
@@ -30,6 +30,8 @@
    like the single-connection that NT makes. */
 
 static char *mutex_server_name;
+/* FIXME. ref_count should be allocated per name... JRA. */
+size_t ref_count;
 
 BOOL grab_server_mutex(const char *name)
 {
@@ -38,7 +40,7 @@ BOOL grab_server_mutex(const char *name)
                DEBUG(0,("grab_server_mutex: malloc failed for %s\n", name));
                return False;
        }
-       if (!secrets_named_mutex(mutex_server_name, 10)) {
+       if (!secrets_named_mutex(mutex_server_name, 10, &ref_count)) {
                DEBUG(10,("grab_server_mutex: failed for %s\n", name));
                SAFE_FREE(mutex_server_name);
                return False;
@@ -50,7 +52,7 @@ BOOL grab_server_mutex(const char *name)
 void release_server_mutex(void)
 {
        if (mutex_server_name) {
-               secrets_named_mutex_release(mutex_server_name);
+               secrets_named_mutex_release(mutex_server_name, &ref_count);
                SAFE_FREE(mutex_server_name);
        }
 }

diff --git a/source3/nsswitch/winbindd_cm.c b/source3/nsswitch/winbindd_cm.c
index 1105c775720eefd6091d64083bce95be2d858f64..54096c0c1d8a712357cf16e7105162a6ab8a740f 100644 (file)
--- a/source3/nsswitch/winbindd_cm.c
+++ b/source3/nsswitch/winbindd_cm.c
@@ -72,6 +72,7 @@ struct winbindd_cm_conn {
        fstring domain;
        fstring controller;
        fstring pipe_name;
+       size_t mutex_ref_count;
        struct cli_state *cli;
        POLICY_HND pol;
 };
@@ -301,7 +302,7 @@ static void add_failed_connection_entry(struct winbindd_cm_conn *new_conn,
 /* Open a connction to the remote server, cache failures for 30 seconds */
 
 static NTSTATUS cm_open_connection(const char *domain, const int pipe_index,
-                              struct winbindd_cm_conn *new_conn)
+                              struct winbindd_cm_conn *new_conn, BOOL keep_mutex)
 {
        struct failed_connection_cache *fcc;
        NTSTATUS result;
@@ -309,6 +310,7 @@ static NTSTATUS cm_open_connection(const char *domain, const int pipe_index,
        struct in_addr dc_ip;
        int i;
        BOOL retry = True;
+       BOOL got_mutex = False;
 
        ZERO_STRUCT(dc_ip);
 
@@ -365,12 +367,23 @@ static NTSTATUS cm_open_connection(const char *domain, const int pipe_index,
 
        for (i = 0; retry && (i < 3); i++) {
                
+               if (!secrets_named_mutex(new_conn->controller, WINBIND_SERVER_MUTEX_WAIT_TIME, &new_conn->mutex_ref_count)) {
+                       DEBUG(0,("cm_open_connection: mutex grab failed for %s\n", new_conn->controller));
+                       result = NT_STATUS_POSSIBLE_DEADLOCK;
+                       continue;
+               }
+
+               got_mutex = True;
+
                result = cli_full_connection(&new_conn->cli, global_myname(), new_conn->controller, 
                        &dc_ip, 0, "IPC$", "IPC", ipc_username, ipc_domain, 
                        ipc_password, 0, &retry);
 
                if (NT_STATUS_IS_OK(result))
                        break;
+
+               secrets_named_mutex_release(new_conn->controller, &new_conn->mutex_ref_count);
+               got_mutex = False;
        }
 
        SAFE_FREE(ipc_username);
@@ -378,6 +391,8 @@ static NTSTATUS cm_open_connection(const char *domain, const int pipe_index,
        SAFE_FREE(ipc_password);
 
        if (!NT_STATUS_IS_OK(result)) {
+               if (got_mutex)
+                       secrets_named_mutex_release(new_conn->controller, &new_conn->mutex_ref_count);
                add_failed_connection_entry(new_conn, result);
                return result;
        }
@@ -392,12 +407,16 @@ static NTSTATUS cm_open_connection(const char *domain, const int pipe_index,
                 * if the PDC is an NT4 box.   but since there is only one 2k 
                 * specific UUID right now, i'm not going to bother.  --jerry
                 */
+               if (got_mutex)
+                       secrets_named_mutex_release(new_conn->controller, &new_conn->mutex_ref_count);
                if ( !is_win2k_pipe(pipe_index) )
                        add_failed_connection_entry(new_conn, result);
                cli_shutdown(new_conn->cli);
                return result;
        }
 
+       if ((got_mutex) && !keep_mutex)
+               secrets_named_mutex_release(new_conn->controller, &new_conn->mutex_ref_count);
        return NT_STATUS_OK;
 }
 
@@ -435,7 +454,8 @@ static BOOL connection_ok(struct winbindd_cm_conn *conn)
 
 /* Get a connection to the remote DC and open the pipe.  If there is already a connection, use that */
 
-static NTSTATUS get_connection_from_cache(const char *domain, const char *pipe_name, struct winbindd_cm_conn **conn_out) 
+static NTSTATUS get_connection_from_cache(const char *domain, const char *pipe_name,
+               struct winbindd_cm_conn **conn_out, BOOL keep_mutex) 
 {
        struct winbindd_cm_conn *conn, conn_temp;
        NTSTATUS result;
@@ -452,6 +472,12 @@ static NTSTATUS get_connection_from_cache(const char *domain, const char *pipe_n
                                SAFE_FREE(conn);
                                conn = &conn_temp;  /* Just to keep the loop moving */
                        } else {
+                               if (keep_mutex) {
+                                       if (!secrets_named_mutex(conn->controller,
+                                                       WINBIND_SERVER_MUTEX_WAIT_TIME, &conn->mutex_ref_count))
+                                               DEBUG(0,("get_connection_from_cache: mutex grab failed for %s\n",
+                                                       conn->controller));
+                               }
                                break;
                        }
                }
@@ -463,7 +489,7 @@ static NTSTATUS get_connection_from_cache(const char *domain, const char *pipe_n
                
                ZERO_STRUCTP(conn);
                
-               if (!NT_STATUS_IS_OK(result = cm_open_connection(domain, get_pipe_index(pipe_name), conn))) {
+               if (!NT_STATUS_IS_OK(result = cm_open_connection(domain, get_pipe_index(pipe_name), conn, keep_mutex))) {
                        DEBUG(3, ("Could not open a connection to %s for %s (%s)\n", 
                                  domain, pipe_name, nt_errstr(result)));
                        SAFE_FREE(conn);
@@ -491,7 +517,7 @@ BOOL cm_check_for_native_mode_win2k( const char *domain )
        ZERO_STRUCT( ctr );
        
        
-       if ( !NT_STATUS_IS_OK(result = cm_open_connection(domain, PI_LSARPC_DS, &conn)) ) {
+       if ( !NT_STATUS_IS_OK(result = cm_open_connection(domain, PI_LSARPC_DS, &conn, False)) ) {
                DEBUG(5, ("cm_check_for_native_mode_win2k: Could not open a connection to %s for PIPE_LSARPC (%s)\n", 
                          domain, nt_errstr(result)));
                return False;
@@ -529,7 +555,7 @@ CLI_POLICY_HND *cm_get_lsa_handle(const char *domain)
 
        /* Look for existing connections */
 
-       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_LSARPC, &conn)))
+       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_LSARPC, &conn, False)))
                return NULL;
 
        /* This *shitty* code needs scrapping ! JRA */
@@ -545,7 +571,7 @@ CLI_POLICY_HND *cm_get_lsa_handle(const char *domain)
        if (!NT_STATUS_IS_OK(result)) {
                /* Hit the cache code again.  This cleans out the old connection and gets a new one */
                if (conn->cli->fd == -1) { /* Try again, if the remote host disapeared */
-                       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_LSARPC, &conn)))
+                       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_LSARPC, &conn, False)))
                                return NULL;
 
                        result = cli_lsa_open_policy(conn->cli, conn->cli->mem_ctx, False, 
@@ -577,7 +603,7 @@ CLI_POLICY_HND *cm_get_sam_handle(char *domain)
 
        /* Look for existing connections */
 
-       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_SAMR, &conn)))
+       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_SAMR, &conn, False)))
                return NULL;
        
        /* This *shitty* code needs scrapping ! JRA */
@@ -592,7 +618,7 @@ CLI_POLICY_HND *cm_get_sam_handle(char *domain)
        if (!NT_STATUS_IS_OK(result)) {
                /* Hit the cache code again.  This cleans out the old connection and gets a new one */
                if (conn->cli->fd == -1) { /* Try again, if the remote host disapeared */
-                       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_SAMR, &conn)))
+                       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_SAMR, &conn, False)))
                                return NULL;
 
                        result = cli_samr_connect(conn->cli, conn->cli->mem_ctx,
@@ -849,28 +875,19 @@ NTSTATUS cm_get_netlogon_cli(const char *domain, const unsigned char *trust_pass
        NTSTATUS result = NT_STATUS_DOMAIN_CONTROLLER_NOT_FOUND;
        struct winbindd_cm_conn *conn;
        uint32 neg_flags = 0x000001ff;
-       fstring srv_name;
-       struct in_addr dc_ip;
 
        if (!cli)
                return NT_STATUS_INVALID_PARAMETER;
 
-       if (!cm_get_dc_name(domain, srv_name, &dc_ip))
-               return NT_STATUS_DOMAIN_CONTROLLER_NOT_FOUND;
+       /* Open an initial conection - keep the mutex. */
 
-       if (!secrets_named_mutex(srv_name, 10)) {
-               DEBUG(0,("cm_get_netlogon_cli: mutex grab failed for %s\n", srv_name));
-               return NT_STATUS_POSSIBLE_DEADLOCK;
-       }
-
-       /* Open an initial conection */
-
-       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_NETLOGON, &conn)))
+       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_NETLOGON, &conn, True)))
                return result;
        
        result = cli_nt_setup_creds(conn->cli, get_sec_chan(), trust_passwd, &neg_flags, 2);
 
-       secrets_named_mutex_release(srv_name);
+       if (conn->mutex_ref_count)
+               secrets_named_mutex_release(conn->controller, &conn->mutex_ref_count);
 
        if (!NT_STATUS_IS_OK(result)) {
                DEBUG(0, ("error connecting to domain password server: %s\n",
@@ -879,18 +896,14 @@ NTSTATUS cm_get_netlogon_cli(const char *domain, const unsigned char *trust_pass
                /* Hit the cache code again.  This cleans out the old connection and gets a new one */
                if (conn->cli->fd == -1) {
 
-                       if (!secrets_named_mutex(srv_name, 10)) {
-                               DEBUG(0,("cm_get_netlogon_cli: mutex grab failed for %s\n", srv_name));
-                               return NT_STATUS_POSSIBLE_DEADLOCK;
-                       }
-
-                       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_NETLOGON, &conn)))
+                       if (!NT_STATUS_IS_OK(result = get_connection_from_cache(domain, PIPE_NETLOGON, &conn, True)))
                                return result;
                        
                        /* Try again */
                        result = cli_nt_setup_creds( conn->cli, get_sec_chan(),trust_passwd, &neg_flags, 2);
 
-                       secrets_named_mutex_release(srv_name);
+                       if (conn->mutex_ref_count)
+                               secrets_named_mutex_release(conn->controller, &conn->mutex_ref_count);
                }
                
                if (!NT_STATUS_IS_OK(result)) {

diff --git a/source3/passdb/secrets.c b/source3/passdb/secrets.c
index 5ba9f1dc1e178d238f0e36c6f2d477a046c4107c..a52e2642705a1a6fe70193a1881335219717c0b7 100644 (file)
--- a/source3/passdb/secrets.c
+++ b/source3/passdb/secrets.c
@@ -588,17 +588,24 @@ NTSTATUS secrets_get_trusted_domains(TALLOC_CTX* ctx, int* enum_ctx, int max_num
  between smbd instances.
 *******************************************************************************/
 
-BOOL secrets_named_mutex(const char *name, unsigned int timeout)
+BOOL secrets_named_mutex(const char *name, unsigned int timeout, size_t *p_ref_count)
 {
-       int ret;
+       size_t ref_count = *p_ref_count;
+       int ret = 0;
 
        if (!message_init())
                return False;
 
-       ret = tdb_lock_bystring(tdb, name, timeout);
-       if (ret == 0)
-               DEBUG(10,("secrets_named_mutex: got mutex for %s\n", name ));
+       if (ref_count == 0) {
+               ret = tdb_lock_bystring(tdb, name, timeout);
+               if (ret == 0)
+                       DEBUG(10,("secrets_named_mutex: got mutex for %s\n", name ));
+       }
 
+       if (ret == 0) {
+               *p_ref_count = ++ref_count;
+               DEBUG(10,("secrets_named_mutex: ref_count for mutex %s = %u\n", name, (unsigned int)ref_count ));
+       }
        return (ret == 0);
 }
 
@@ -606,10 +613,19 @@ BOOL secrets_named_mutex(const char *name, unsigned int timeout)
  Unlock a named mutex.
 *******************************************************************************/
 
-void secrets_named_mutex_release(const char *name)
+void secrets_named_mutex_release(const char *name, size_t *p_ref_count)
 {
-       tdb_unlock_bystring(tdb, name);
-       DEBUG(10,("secrets_named_mutex: released mutex for %s\n", name ));
+       size_t ref_count = *p_ref_count;
+
+       SMB_ASSERT(ref_count != 0);
+
+       if (ref_count == 1) {
+               tdb_unlock_bystring(tdb, name);
+               DEBUG(10,("secrets_named_mutex: released mutex for %s\n", name ));
+       }
+
+       *p_ref_count = --ref_count;
+       DEBUG(10,("secrets_named_mutex_release: ref_count for mutex %s = %u\n", name, (unsigned int)ref_count ));
 }
 
 /*********************************************************