On Fri, Jan 3, 2020 at 12:27 AM Simon Horman <simon.horman@xxxxxxxxxxxxx> wrote: > > On Fri, Jan 03, 2020 at 02:02:33PM +0800, Li RongQing wrote: > > bpf_skb_generic_push always returns 0, not need to check > > its return, so change its type as void > > > > Signed-off-by: Li RongQing <lirongqing@xxxxxxxxx> > > Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxxx> Acked-by: Song Liu <songliubraving@xxxxxx> > > > --- > > net/core/filter.c | 30 ++++++++++-------------------- > > 1 file changed, 10 insertions(+), 20 deletions(-) > > > > diff --git a/net/core/filter.c b/net/core/filter.c > > index 42fd17c48c5f..1cbac34a4e11 100644 > > --- a/net/core/filter.c > > +++ b/net/core/filter.c > > ... > > > @@ -5144,7 +5134,7 @@ BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset, > > if (unlikely(ret < 0)) > > return ret; > > > > - ret = bpf_skb_net_hdr_push(skb, offset, len); > > + bpf_skb_net_hdr_push(skb, offset, len); > > There is a check for (ret < 0) just below this if block. > That is ok becuase in order to get to here (ret < 0) must > be true as per the check a few lines above. > > So I think this is ok although the asymmetry with the else arm > of this if statement is not ideal IMHO. Agreed with this concern. But I cannot think of any free solution. I guess we will just live with assumption that skb_cow_head() never return >0. Thanks, Song
