Hi,
Please, withdraw this patch.
I can fix this by using TCPHDR_* definitions.
Thanks.
On Mon, Dec 09, 2019 at 04:55:30PM +0100, Pablo Neira Ayuso wrote:
> net/netfilter/nf_flow_table_offload.c: In function 'nf_flow_rule_match':
> net/netfilter/nf_flow_table_offload.c:80:21: warning: unsigned conversion from 'int' to '__be16' {aka 'short unsigned int'} changes value from '327680' to '0' [-Woverflow]
> 80 | mask->tcp.flags = TCP_FLAG_RST | TCP_FLAG_FIN;
> | ^~~~~~~~~~~~
>
> Fixes: ac4bb5de2701 ("net: flow_dissector: add support for dissection of tcp flags")
> Fixes: c29f74e0df7a ("netfilter: nf_flow_table: hardware offload support")
> Reported-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
> ---
> @Geert: I have removed the pad field and included the nitpick fix on the
> comment, given I have slightly updated this patch, I would prefer
> if you can provide a fresh Reviewed-by tag. Thanks.
>
> include/net/flow_dissector.h | 8 ++++++--
> net/core/flow_dissector.c | 2 +-
> net/netfilter/nf_flow_table_offload.c | 4 ++--
> 3 files changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h
> index b8c20e9f343e..9ff8dac9d5ec 100644
> --- a/include/net/flow_dissector.h
> +++ b/include/net/flow_dissector.h
> @@ -189,10 +189,14 @@ struct flow_dissector_key_eth_addrs {
>
> /**
> * struct flow_dissector_key_tcp:
> - * @flags: flags
> + * @flags: TCP flags, including the initial Data offset field bits (16-bits)
> + * @flag_word: Data offset + reserved bits + TCP flags + window (32-bits)
> */
> struct flow_dissector_key_tcp {
> - __be16 flags;
> + union {
> + __be16 flags;
> + __be32 flag_word;
> + };
> };
>
> /**
> diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
> index ca871657a4c4..83af4633f306 100644
> --- a/net/core/flow_dissector.c
> +++ b/net/core/flow_dissector.c
> @@ -756,7 +756,7 @@ __skb_flow_dissect_tcp(const struct sk_buff *skb,
> key_tcp = skb_flow_dissector_target(flow_dissector,
> FLOW_DISSECTOR_KEY_TCP,
> target_container);
> - key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF));
> + key_tcp->flag_word = tcp_flag_word(th);
> }
>
> static void
> diff --git a/net/netfilter/nf_flow_table_offload.c b/net/netfilter/nf_flow_table_offload.c
> index c94ebad78c5c..30205d57226d 100644
> --- a/net/netfilter/nf_flow_table_offload.c
> +++ b/net/netfilter/nf_flow_table_offload.c
> @@ -87,8 +87,8 @@ static int nf_flow_rule_match(struct nf_flow_match *match,
>
> switch (tuple->l4proto) {
> case IPPROTO_TCP:
> - key->tcp.flags = 0;
> - mask->tcp.flags = TCP_FLAG_RST | TCP_FLAG_FIN;
> + key->tcp.flag_word = 0;
> + mask->tcp.flag_word = TCP_FLAG_RST | TCP_FLAG_FIN;
> match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_TCP);
> break;
> case IPPROTO_UDP:
> --
> 2.11.0
>
