releases/4.4.181/ethtool-check-the-return-value-of-get_regs_len.patch

   1 From f9fc54d313fab2834f44f516459cdc8ac91d797f Mon Sep 17 00:00:00 2001
   2 From: Yunsheng Lin <linyunsheng@huawei.com>
   3 Date: Wed, 26 Dec 2018 19:51:46 +0800
   4 Subject: ethtool: check the return value of get_regs_len
   5
   6 From: Yunsheng Lin <linyunsheng@huawei.com>
   7
   8 commit f9fc54d313fab2834f44f516459cdc8ac91d797f upstream.
   9
  10 The return type for get_regs_len in struct ethtool_ops is int,
  11 the hns3 driver may return error when failing to get the regs
  12 len by sending cmd to firmware.
  13
  14 Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
  15 Signed-off-by: David S. Miller <davem@davemloft.net>
  16 Cc: Michal Kubecek <mkubecek@suse.cz>
  17 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  18
  19 ---
  20  net/core/ethtool.c |   12 ++++++++++--
  21  1 file changed, 10 insertions(+), 2 deletions(-)
  22
  23 --- a/net/core/ethtool.c
  24 +++ b/net/core/ethtool.c
  25 @@ -428,8 +428,13 @@ static noinline_for_stack int ethtool_ge
  26                 if (rc >= 0)
  27                         info.n_priv_flags = rc;
  28         }
  29 -       if (ops->get_regs_len)
  30 -               info.regdump_len = ops->get_regs_len(dev);
  31 +       if (ops->get_regs_len) {
  32 +               int ret = ops->get_regs_len(dev);
  33 +
  34 +               if (ret > 0)
  35 +                       info.regdump_len = ret;
  36 +       }
  37 +
  38         if (ops->get_eeprom_len)
  39                 info.eedump_len = ops->get_eeprom_len(dev);
  40
  41 @@ -883,6 +888,9 @@ static int ethtool_get_regs(struct net_d
  42                 return -EFAULT;
  43
  44         reglen = ops->get_regs_len(dev);
  45 +       if (reglen <= 0)
  46 +               return reglen;
  47 +
  48         if (regs.len > reglen)
  49                 regs.len = reglen;
  50