Re: [PATCH] sctp: remove redundant chunk length check

[Shan Wei <shanwei@cn.fujitsu.com>]

Nicolas Kaiser wrote, at 10/21/2010 06:14 PM:
> Checking the chunk length at this point appears redundant, as
> the rest of the packet gets discarded anyway.
> 
> Signed-off-by: Nicolas Kaiser <nikai@nikai.net>

Yes, indeed.

How did you find this? By reviewing the source code?

-- 
Best Regards
-----
Shan Wei

> ---
>  net/sctp/sm_statefuns.c |    6 ------
>  1 files changed, 0 insertions(+), 6 deletions(-)
> 
> diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
> index 4b4eb7c..9840615 100644
> --- a/net/sctp/sm_statefuns.c
> +++ b/net/sctp/sm_statefuns.c
> @@ -3418,12 +3418,6 @@ static sctp_disposition_t sctp_sf_shut_8_4_5(const struct sctp_endpoint *ep,
>  
>  		SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS);
>  
> -		/* If the chunk length is invalid, we don't want to process
> -		 * the reset of the packet.
> -		 */
> -		if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
> -			return sctp_sf_pdiscard(ep, asoc, type, arg, commands);
> -
>  		/* We need to discard the rest of the packet to prevent
>  		 * potential bomming attacks from additional bundled chunks.
>  		 * This is documented in SCTP Threats ID.