[PATCH 13/44] net: mana: Fix return type of mana_start_xmit()
authorNathan Huckleberry <nhuck@google.com>
Wed, 9 Nov 2022 00:26:30 +0000 (17:26 -0700)
committerSalvatore Bonaccorso <carnil@debian.org>
Fri, 25 Apr 2025 19:51:43 +0000 (21:51 +0200)
commit6f2dbeb300c282f3543663e3f91888c2304321e6
tree429e8c1165cde35755949ad16e3e861c4bf46558
parente94e4b9cc976d2ebe7f6ecd8304315d8a04cd89d
[PATCH 13/44] net: mana: Fix return type of mana_start_xmit()

The ndo_start_xmit field in net_device_ops is expected to be of type
netdev_tx_t (*ndo_start_xmit)(struct sk_buff *skb, struct net_device *dev).

The mismatched return type breaks forward edge kCFI since the underlying
function definition does not match the function hook definition. A new
warning in clang will catch this at compile time:

  drivers/net/ethernet/microsoft/mana/mana_en.c:382:21: error: incompatible function pointer types initializing 'netdev_tx_t (*)(struct sk_buff *, struct net_device *)' (aka 'enum netdev_tx (*)(struct sk_buff *, struct net_device *)') with an expression of type 'int (struct sk_buff *, struct net_device *)' [-Werror,-Wincompatible-function-pointer-types-strict]
          .ndo_start_xmit         = mana_start_xmit,
                                    ^~~~~~~~~~~~~~~
  1 error generated.

The return type of mana_start_xmit should be changed from int to
netdev_tx_t.

Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1703
Link: https://github.com/ClangBuiltLinux/linux/issues/1750
Signed-off-by: Nathan Huckleberry <nhuck@google.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
[nathan: Rebase on net-next and resolve conflicts
         Add note about new clang warning]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20221109002629.1446680-1-nathan@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
(cherry picked from commit 0c9ef08a4d0fd6c5e6000597b506235d71a85a61)
Signed-off-by: Bastian Blank <waldi@debian.org>
Gbp-Pq: Topic features/all/ethernet-microsoft
Gbp-Pq: Name 0013-net-mana-Fix-return-type-of-mana_start_xmit.patch
drivers/net/ethernet/microsoft/mana/mana_en.c
include/net/mana/mana.h