Hi Cong, On 06/30/2016 07:15 PM, Cong Wang wrote:
Similar to commit 9b368814b336 ("net: fix bridge multicast packet checksum validation") we need to fixup the checksum for CHECKSUM_COMPLETE when pushing skb on RX path. Otherwise we get similar splats.Cc: Jamal Hadi Salim <j...@mojatatu.com> Cc: Tom Herbert <t...@herbertland.com> Signed-off-by: Cong Wang <xiyou.wangc...@gmail.com> --- include/linux/skbuff.h | 19 +++++++++++++++++++ net/core/skbuff.c | 18 ------------------ net/sched/act_mirred.c | 2 +- 3 files changed, 20 insertions(+), 19 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index ee38a41..61ab566 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -2870,6 +2870,25 @@ static inline void skb_postpush_rcsum(struct sk_buff *skb, } /** + * skb_push_rcsum - push skb and update receive checksum + * @skb: buffer to update + * @len: length of data pulled + * + * This function performs an skb_push on the packet and updates + * the CHECKSUM_COMPLETE checksum. It should be used on + * receive path processing instead of skb_push unless you know + * that the checksum difference is zero (e.g., a valid IP header) + * or you are setting ip_summed to CHECKSUM_NONE. + */ +static inline unsigned char *skb_push_rcsum(struct sk_buff *skb, + unsigned int len) +{ + skb_push(skb, len); + skb_postpush_rcsum(skb, skb->data, len); + return skb->data; +} + +/** * pskb_trim_rcsum - trim received skb and update checksum * @skb: buffer to trim * @len: new length diff --git a/net/core/skbuff.c b/net/core/skbuff.c index f2b77e5..eb12d21 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3016,24 +3016,6 @@ int skb_append_pagefrags(struct sk_buff *skb, struct page *page, EXPORT_SYMBOL_GPL(skb_append_pagefrags); /** - * skb_push_rcsum - push skb and update receive checksum - * @skb: buffer to update - * @len: length of data pulled - * - * This function performs an skb_push on the packet and updates - * the CHECKSUM_COMPLETE checksum. It should be used on - * receive path processing instead of skb_push unless you know - * that the checksum difference is zero (e.g., a valid IP header) - * or you are setting ip_summed to CHECKSUM_NONE. - */ -static unsigned char *skb_push_rcsum(struct sk_buff *skb, unsigned len) -{ - skb_push(skb, len); - skb_postpush_rcsum(skb, skb->data, len); - return skb->data; -} - -/** * skb_pull_rcsum - pull skb and update receive checksum * @skb: buffer to update * @len: length of data pulled
Fix looks good to me, just a minor comment. Maybe makes sense to move skb_push_rcsum() but /also/ skb_pull_rcsum() to the header then? Both seem similarly small at least (could be split f.e into two patches then, first for the move, second for the actual fix). Thanks, Daniel
