On Thu, Dec 20, 2018 at 5:20 AM Herbert Xu <herb...@gondor.apana.org.au> wrote:
>
> It was reported that IPsec would crash when it encounters an IPv6
> reassembled packet because skb->sk is non-zero and not a valid
> pointer.
>
> This is because skb->sk is now a union with ip_defrag_offset.
>
> This patch fixes this by resetting skb->sk when exiting from
> the reassembly code.
>
> Reported-by: Xiumei Mu <x...@redhat.com>
> Fixes: 219badfaade9 ("ipv6: frags: get rid of ip6frag_skb_cb/...")
> Signed-off-by: Herbert Xu <herb...@gondor.apana.org.au>
>
> diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
> index 5c3c92713096..a98f95fb6eac 100644
> --- a/net/ipv6/reassembly.c
> +++ b/net/ipv6/reassembly.c
> @@ -378,6 +378,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct
> sk_buff *prev,
> if (skb_try_coalesce(head, fp, &headstolen, &delta)) {
> kfree_skb_partial(fp, headstolen);
> } else {
> + fp->sk = NULL;
> if (!skb_shinfo(head)->frag_list)
> skb_shinfo(head)->frag_list = fp;
> head->data_len += fp->len;
I wonder why this have not been done earlier in commit
commit 5d407b071dc369c26a38398326ee2be53651cfe4
Author: Taehee Yoo <ap420...@gmail.com>
Date: Mon Sep 10 02:47:05 2018 +0900
ip: frags: fix crash in ip_do_fragment()
Maybe because the Fixes tag mentioned fa0f527358bd ("ip: use rb trees
for IP frag queue.")
and IPv6 reasm was not using rbtree ...
Oh well.
