target/linux/generic/backport-5.15/733-v6.4-23-net-ethernet-mtk_eth_soc-fix-NULL-pointer-dereferenc.patch

   1 From 7c83e28f10830aa5105c25eaabe890e3adac36aa Mon Sep 17 00:00:00 2001
   2 From: Daniel Golle <daniel@makrotopia.org>
   3 Date: Tue, 9 May 2023 03:20:06 +0200
   4 Subject: [PATCH] net: ethernet: mtk_eth_soc: fix NULL pointer dereference
   5
   6 Check for NULL pointer to avoid kernel crashing in case of missing WO
   7 firmware in case only a single WEDv2 device has been initialized, e.g. on
   8 MT7981 which can connect just one wireless frontend.
   9
  10 Fixes: 86ce0d09e424 ("net: ethernet: mtk_eth_soc: use WO firmware for MT7981")
  11 Signed-off-by: Daniel Golle <daniel@makrotopia.org>
  12 Reviewed-by: Simon Horman <simon.horman@corigine.com>
  13 Signed-off-by: David S. Miller <davem@davemloft.net>
  14 ---
  15  drivers/net/ethernet/mediatek/mtk_wed.c | 2 +-
  16  1 file changed, 1 insertion(+), 1 deletion(-)
  17
  18 --- a/drivers/net/ethernet/mediatek/mtk_wed.c
  19 +++ b/drivers/net/ethernet/mediatek/mtk_wed.c
  20 @@ -647,7 +647,7 @@ __mtk_wed_detach(struct mtk_wed_device *
  21                                            BIT(hw->index), BIT(hw->index));
  22         }
  23
  24 -       if (!hw_list[!hw->index]->wed_dev &&
  25 +       if ((!hw_list[!hw->index] || !hw_list[!hw->index]->wed_dev) &&
  26             hw->eth->dma_dev != hw->eth->dev)
  27                 mtk_eth_set_dma_device(hw->eth, hw->eth->dev);
  28