cc Frantisek
On Mon, 1 Jun 2020 at 12:00, Hangbin Liu <liuhangbin@xxxxxxxxx> wrote:
>
> Socket option IPV6_ADDRFORM supports UDP/UDPLITE and TCP at present.
> Previously the checking logic looks like:
> if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE)
> do_some_check;
> else if (sk->sk_protocol != IPPROTO_TCP)
> break;
>
> After commit b6f6118901d1 ("ipv6: restrict IPV6_ADDRFORM operation"), TCP
> was blocked as the logic changed to:
> if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE)
> do_some_check;
> else if (sk->sk_protocol == IPPROTO_TCP)
> do_some_check;
> break;
> else
> break;
>
> Then after commit 82c9ae440857 ("ipv6: fix restrict IPV6_ADDRFORM operation")
> UDP/UDPLITE were blocked as the logic changed to:
> if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE)
> do_some_check;
> if (sk->sk_protocol == IPPROTO_TCP)
> do_some_check;
>
> if (sk->sk_protocol != IPPROTO_TCP)
> break;
>
> Fix it by using Eric's code and simply remove the break in TCP check, which
> looks like:
> if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE)
> do_some_check;
> else if (sk->sk_protocol == IPPROTO_TCP)
> do_some_check;
> else
> break;
>
> Fixes: 82c9ae440857 ("ipv6: fix restrict IPV6_ADDRFORM operation")
> Signed-off-by: Hangbin Liu <liuhangbin@xxxxxxxxx>
> ---
> net/ipv6/ipv6_sockglue.c | 13 +++++++------
> 1 file changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
> index 18d05403d3b5..5af97b4f5df3 100644
> --- a/net/ipv6/ipv6_sockglue.c
> +++ b/net/ipv6/ipv6_sockglue.c
> @@ -183,14 +183,15 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
> retv = -EBUSY;
> break;
> }
> - }
> - if (sk->sk_protocol == IPPROTO_TCP &&
> - sk->sk_prot != &tcpv6_prot) {
> - retv = -EBUSY;
> + } else if (sk->sk_protocol == IPPROTO_TCP) {
> + if (sk->sk_prot != &tcpv6_prot) {
> + retv = -EBUSY;
> + break;
> + }
> + } else {
> break;
> }
> - if (sk->sk_protocol != IPPROTO_TCP)
> - break;
> +
> if (sk->sk_state != TCP_ESTABLISHED) {
> retv = -ENOTCONN;
> break;
> --
> 2.25.4
>
