liujian (CE) wrote: > > > > -----Original Message----- > > From: Martin KaFai Lau [mailto:kafai@xxxxxx] > > Sent: Wednesday, March 16, 2022 3:58 AM > > To: liujian (CE) <liujian56@xxxxxxxxxx> > > Cc: ast@xxxxxxxxxx; daniel@xxxxxxxxxxxxx; andrii@xxxxxxxxxx; > > songliubraving@xxxxxx; yhs@xxxxxx; john.fastabend@xxxxxxxxx; > > kpsingh@xxxxxxxxxx; davem@xxxxxxxxxxxxx; kuba@xxxxxxxxxx; > > sdf@xxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; bpf@xxxxxxxxxxxxxxx > > Subject: Re: [PATCH bpf-next] net: Use skb->len to check the validity of the > > parameters in bpf_skb_load_bytes > > > > On Tue, Mar 15, 2022 at 08:39:16PM +0800, Liu Jian wrote: > > > The data length of skb frags + frag_list may be greater than 0xffff, > > > so here use skb->len to check the validity of the parameters. > > What is the use case that needs to look beyond 0xffff ? > I use sockmap with strparser, the stm->strp.offset (the begin of one > application layer protocol message) maybe beyond 0xffff, but i need > load the message head to do something. This would explain skb_load_bytes but not the other two right? Also if we are doing this why not just remove those two checks in flow_dissector_load() I think skb_header_pointer() does duplicate checks. Please check.
