Re: [PATCH] Revert "net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends"

From: Andreas Schwab
Date: Mon Jun 18 2018 - 13:54:57 EST


On Jun 17 2018, Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote:

> Oh this is silly, please try :
>
> diff --git a/net/core/skbuff.c b/net/core/skbuff.c
> index c642304f178ce0a4e1358d59e45032a39f76fb3f..54dd9c18ecad817812898d6f335e1794a07dabbe 100644
> --- a/net/core/skbuff.c
> +++ b/net/core/skbuff.c
> @@ -1845,10 +1845,9 @@ EXPORT_SYMBOL(___pskb_trim);
> int pskb_trim_rcsum_slow(struct sk_buff *skb, unsigned int len)
> {
> if (skb->ip_summed == CHECKSUM_COMPLETE) {
> - int delta = skb->len - len;
> + __wsum csumdiff = skb_checksum(skb, len, skb->len - len, 0);
>
> - skb->csum = csum_sub(skb->csum,
> - skb_checksum(skb, len, delta, 0));
> + skb->csum = csum_block_sub(skb->csum, csumdiff, len);
> }
> return __pskb_trim(skb, len);
> }

That doesn't help either.

Andreas.

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Andreas Schwab, schwab@xxxxxxxxxxxxxx
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