mlx4: fix error path in drivers/net/mlx4/en_rx.c

this warning:

  drivers/net/mlx4/en_rx.c: In function ‘mlx4_en_activate_rx_rings’:
  drivers/net/mlx4/en_rx.c:412: warning: ‘err’ may be used uninitialized in this function

Triggers because 'err' is uninitialized in the following input
conditions: priv->rx_ring_num is zero and mlx4_en_fill_rx_buffers()
fails.

But even if ->rx_ring_num is nonzero, 'err' will be zero if
mlx4_en_fill_rx_buffers() fails and mlx4_en_activate_rx_rings() returns
success - incorrectly.

So it's best to keep the error code uptodate on mlx4_en_fill_rx_buffers()
calls as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/net/mlx4/en_rx.c b/drivers/net/mlx4/en_rx.c
index 944ad47c9519..ffe28089b687 100644
--- a/drivers/net/mlx4/en_rx.c
+++ b/drivers/net/mlx4/en_rx.c
@@ -443,7 +443,8 @@ int mlx4_en_activate_rx_rings(struct mlx4_en_priv *priv)
                 /* Fill Rx buffers */
                 ring->full = 0;
         }
-        if (mlx4_en_fill_rx_buffers(priv))
+        err = mlx4_en_fill_rx_buffers(priv);
+        if (err)
                 goto err_buffers;
 
         for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {