On Fri, Mar 12, 2021 at 09:08 PM CET, Alexander Lobakin wrote:
> flow_dissector_key_icmp::id is of type u16 (CPU byteorder),
> ICMP header has its ID field in network byteorder obviously.
> Sparse says:
>
> net/core/flow_dissector.c:178:43: warning: restricted __be16 degrades to
> integer
>
> Convert ID value to CPU byteorder when storing it into
> flow_dissector_key_icmp.
>
> Fixes: 5dec597e5cd0 ("flow_dissector: extract more ICMP information")
> Signed-off-by: Alexander Lobakin <aloba...@pm.me>
> ---
> net/core/flow_dissector.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
> index 2ef2224b3bff..a96a4f5de0ce 100644
> --- a/net/core/flow_dissector.c
> +++ b/net/core/flow_dissector.c
> @@ -176,7 +176,7 @@ void skb_flow_get_icmp_tci(const struct sk_buff *skb,
> * avoid confusion with packets without such field
> */
> if (icmp_has_id(ih->type))
> - key_icmp->id = ih->un.echo.id ? : 1;
> + key_icmp->id = ih->un.echo.id ? ntohs(ih->un.echo.id) : 1;
> else
> key_icmp->id = 0;
> }
Smells like a breaking change for existing consumers of this value.
How about we change the type of flow_dissector_key_icmp{}.id to __be16
instead to make sparse happy?
