[PATCH] thunderbolt: Fix to check for kmemdup failure

[Aditya Pakki]

Memory allocated via kmemdup might fail and return a NULL pointer.
This patch adds a check on the return value of kmemdup and passes the
error upstream.

Signed-off-by: Aditya Pakki <pakki...@umn.edu>
---
 drivers/thunderbolt/switch.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index cd96994dc094..c05d77073ee7 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -1294,13 +1294,13 @@ int tb_switch_configure(struct tb_switch *sw)
        return tb_plug_events_active(sw, true);
 }
 
-static void tb_switch_set_uuid(struct tb_switch *sw)
+static int tb_switch_set_uuid(struct tb_switch *sw)
 {
        u32 uuid[4];
        int cap;
 
        if (sw->uuid)
-               return;
+               return 0;
 
        /*
         * The newer controllers include fused UUID as part of link
@@ -1323,6 +1323,9 @@ static void tb_switch_set_uuid(struct tb_switch *sw)
        }
 
        sw->uuid = kmemdup(uuid, sizeof(uuid), GFP_KERNEL);
+       if (!sw->uuid)
+               return -ENOMEM;
+       return 0;
 }
 
 static int tb_switch_add_dma_port(struct tb_switch *sw)
@@ -1372,7 +1375,9 @@ static int tb_switch_add_dma_port(struct tb_switch *sw)
 
        if (status) {
                tb_sw_info(sw, "switch flash authentication failed\n");
-               tb_switch_set_uuid(sw);
+               ret = tb_switch_set_uuid(sw);
+               if (ret)
+                       return ret;
                nvm_set_auth_status(sw, status);
        }
 
@@ -1422,7 +1427,9 @@ int tb_switch_add(struct tb_switch *sw)
                }
                tb_sw_dbg(sw, "uid: %#llx\n", sw->uid);
 
-               tb_switch_set_uuid(sw);
+               ret = tb_switch_set_uuid(sw);
+               if (ret)
+                       return ret;
 
                for (i = 0; i <= sw->config.max_port_number; i++) {
                        if (sw->ports[i].disabled) {
-- 
2.17.1