On Sun, Jun 02, 2019 at 11:24:18AM -0700, Eric Dumazet wrote:
> syzbot reported nasty use-after-free [1]
>
> Lets remove frag_list field from structs ip_fraglist_iter
> and ip6_fraglist_iter. This seens not needed anyway.
>
> [1] :
> BUG: KASAN: use-after-free in kfree_skb_list+0x5d/0x60 net/core/skbuff.c:706
> Read of size 8 at addr ffff888085a3cbc0 by task syz-executor303/8947
[...]
>
> Memory state around the buggy address:
> ffff888085a3ca80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> ffff888085a3cb00: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
> >ffff888085a3cb80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
> ^
> ffff888085a3cc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff888085a3cc80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
>
> Fixes: 0feca6190f88 ("net: ipv6: add skbuff fraglist splitter")
> Fixes: c8b17be0b7a4 ("net: ipv4: add skbuff fraglist splitter")
> Signed-off-by: Eric Dumazet <[email protected]>
> Cc: Pablo Neira Ayuso <[email protected]>
Acked-by: Pablo Neira Ayuso <[email protected]>
Thanks!
