Re: [PATCH] staging: octeon: Fix return type of cvm_oct_xmit and cvm_oct_xmit_pow

Nathan Chancellor
2022-09-13T22:33:26Z

On Mon, Sep 12, 2022 at 02:45:20PM -0700, Nathan Huckleberry wrote:
> 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.
>
> The return type of cvm_oct_xmit and cvm_oct_xmit_pow should be changed
> from int to netdev_tx_t.
>
> Reported-by: Dan Carpenter <error27@gmail.com>
> Link: https://github.com/ClangBuiltLinux/linux/issues/1703
> Cc: llvm@lists.linux.dev
> Signed-off-by: Nathan Huckleberry <nhuck@google.com>

Reviewed-by: Nathan Chancellor <nathan@kernel.org>

> ---
> drivers/staging/octeon/ethernet-tx.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/octeon/ethernet-tx.c b/drivers/staging/octeon/ethernet-tx.c
> index 1ad94c5060b5..a36e36701c74 100644
> --- a/drivers/staging/octeon/ethernet-tx.c
> +++ b/drivers/staging/octeon/ethernet-tx.c
> @@ -125,7 +125,7 @@ static void cvm_oct_free_tx_skbs(struct net_device *dev)
> *
> * Returns Always returns NETDEV_TX_OK
> */
> -int cvm_oct_xmit(struct sk_buff *skb, struct net_device *dev)
> +netdev_tx_t cvm_oct_xmit(struct sk_buff *skb, struct net_device *dev)
> {
> union cvmx_pko_command_word0 pko_command;
> union cvmx_buf_ptr hw_buffer;
> @@ -506,7 +506,7 @@ int cvm_oct_xmit(struct sk_buff *skb, struct net_device *dev)
> * @dev: Device info structure
> * Returns Always returns zero
> */
> -int cvm_oct_xmit_pow(struct sk_buff *skb, struct net_device *dev)
> +netdev_tx_t cvm_oct_xmit_pow(struct sk_buff *skb, struct net_device *dev)
> {
> struct octeon_ethernet *priv = netdev_priv(dev);
> void *packet_buffer;
> --
> 2.37.2.789.g6183377224-goog
>