be2net: Free/delete pmacs (in be_clear()) only if they exist

During suspend-resume and lancer error recovery we will cleanup and
re-initialize the resources through be_clear() and be_setup() respectively.
During re-initialisation in be_setup(), if be_get_config() fails, we'll again
call be_clear() which will cause a NULL pointer dereference as adapter->pmac_id is
already freed.

Signed-off-by: Kalesh AP <kalesh.purayil@emulex.com>
Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 15 insertions, 8 deletions

diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index a2302dc061f3..0fde69d5cb6a 100644
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -2940,28 +2940,35 @@ static void be_cancel_worker(struct be_adapter *adapter)
         }
 }
 
-static int be_clear(struct be_adapter *adapter)
+static void be_mac_clear(struct be_adapter *adapter)
 {
         int i;
 
+        if (adapter->pmac_id) {
+                for (i = 0; i < (adapter->uc_macs + 1); i++)
+                        be_cmd_pmac_del(adapter, adapter->if_handle,
+                                        adapter->pmac_id[i], 0);
+                adapter->uc_macs = 0;
+
+                kfree(adapter->pmac_id);
+                adapter->pmac_id = NULL;
+        }
+}
+
+static int be_clear(struct be_adapter *adapter)
+{
         be_cancel_worker(adapter);
 
         if (sriov_enabled(adapter))
                 be_vf_clear(adapter);
 
         /* delete the primary mac along with the uc-mac list */
-        for (i = 0; i < (adapter->uc_macs + 1); i++)
-                be_cmd_pmac_del(adapter, adapter->if_handle,
-                                adapter->pmac_id[i], 0);
-        adapter->uc_macs = 0;
+        be_mac_clear(adapter);
 
         be_cmd_if_destroy(adapter, adapter->if_handle,  0);
 
         be_clear_queues(adapter);
 
-        kfree(adapter->pmac_id);
-        adapter->pmac_id = NULL;
-
         be_msix_disable(adapter);
         return 0;
 }