net/smc: fix cleanup for linkgroup setup failures
If an SMC connection to a certain peer is setup the first time,
a new linkgroup is created. In case of setup failures, such a
linkgroup is unusable and should disappear. As a first step the
linkgroup is removed from the linkgroup list in smc_lgr_forget().
There are 2 problems:
smc_listen_decline() might be called before linkgroup creation
resulting in a crash due to calling smc_lgr_forget() with
parameter NULL.
If a setup failure occurs after linkgroup creation, the connection
is never unregistered from the linkgroup, preventing linkgroup
freeing.
This patch introduces an enhanced smc_lgr_cleanup_early() function
which
* contains a linkgroup check for early smc_listen_decline()
invocations
* invokes smc_conn_free() to guarantee unregistering of the
connection.
* schedules fast linkgroup removal of the unusable linkgroup
And the unused function smcd_conn_free() is removed from smc_core.h.
Fixes: 3b2dec2603d5b ("net/smc: restructure client and server code in af_smc")
Fixes: 2a0674fffb6bc ("net/smc: improve abnormal termination of link groups")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 2249de5..5b085ef 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -162,6 +162,18 @@ static void smc_lgr_unregister_conn(struct smc_connection *conn)
conn->lgr = NULL;
}
+void smc_lgr_cleanup_early(struct smc_connection *conn)
+{
+ struct smc_link_group *lgr = conn->lgr;
+
+ if (!lgr)
+ return;
+
+ smc_conn_free(conn);
+ smc_lgr_forget(lgr);
+ smc_lgr_schedule_free_work_fast(lgr);
+}
+
/* Send delete link, either as client to request the initiation
* of the DELETE LINK sequence from server; or as server to
* initiate the delete processing. See smc_llc_rx_delete_link().
