Re: [net-next fragmenation icmp 1/2] ipv4_fragment: Add a bit in IPCB to control ICMP generation

[Andy Zhou <azhou@nicira.com>]

Since I only need 1 bit for this, I can probably define and use one
more bit in the 'flags' field above.

Thanks for the review.  I will send out a 'v2'.


On Wed, May 6, 2015 at 5:23 AM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> On Tue, 2015-05-05 at 18:59 -0700, Andy Zhou wrote:
>> Currently, on fragmentation or defragmentation error, ICMP error message
>> can be generated. This is fine when they are used in a routing context,
>> but does not make sense when they are used in a bridging context, i.e.
>> netfilter for bridging.
>>
>> This patch adds a bit in IPCB to control whether ICMP error message
>> should be generated.
>>
>> IPV6 fragmentation and defragmentation functions are not reused by
>> bridge netfilter. Thus, this change is only required for IPV4.
>>
>> Signed-off-by: Andy Zhou <azhou@nicira.com>
>> ---
>>  include/net/inet_frag.h |  2 ++
>>  include/net/ip.h        |  1 +
>>  net/ipv4/ip_fragment.c  | 11 ++++++++++-
>>  net/ipv4/ip_output.c    |  5 +++--
>>  4 files changed, 16 insertions(+), 3 deletions(-)
>>
>> diff --git a/include/net/inet_frag.h b/include/net/inet_frag.h
>> index 8d17655..1d57045 100644
>> --- a/include/net/inet_frag.h
>> +++ b/include/net/inet_frag.h
>> @@ -44,6 +44,7 @@ enum {
>>   * @meat: length of received fragments so far
>>   * @flags: fragment queue flags
>>   * @max_size: (ipv4 only) maximum received fragment size with IP_DF set
>> + * @no_icmp:  Do not generate any fragmentation related icmp packet
>>   * @net: namespace that this frag belongs to
>>   */
>>  struct inet_frag_queue {
>> @@ -58,6 +59,7 @@ struct inet_frag_queue {
>>       int                     meat;
>>       __u8                    flags;
>>       u16                     max_size;
>> +     bool                    no_icmp;
>>       struct netns_frags      *net;
>>  };
>>
>
>
> What about filling the 8bit hole ?
>
>         int                     meat;
>         __u8                    flags;
> +       bool                    no_icmp;
>         u16                     max_size;
>         struct netns_frags      *net;
>
>
>