Re: [PATCH net] net: make skb_partial_csum_set() more robust against overflows

2018-10-10 Thread David Miller
From: Eric Dumazet Date: Wed, 10 Oct 2018 06:59:35 -0700 > syzbot managed to crash in skb_checksum_help() [1] : > > BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb)); > > Root cause is the following check in skb_partial_csum_set() > > if (unlikely(start > skb_headlen(skb)) || >

[PATCH net] net: make skb_partial_csum_set() more robust against overflows

2018-10-10 Thread Eric Dumazet
syzbot managed to crash in skb_checksum_help() [1] : BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb)); Root cause is the following check in skb_partial_csum_set() if (unlikely(start > skb_headlen(skb)) || unlikely((int)start + off > skb_headlen(skb) - 2))