Commit b84d2b73 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by David S. Miller
Browse files

net/ipv6: factor out a ipv6_set_opt_hdr helper 



Factour out a helper to set the IPv6 option headers from
do_ipv6_setsockopt.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 86298285

net/ipv6/ipv6_sockglue.c

+75 −75
Original line number Diff line number Diff line
@@ -315,6 +315,80 @@ static int compat_ipv6_mcast_join_leave(struct sock *sk, int optname, 
	return ipv6_sock_mc_drop(sk, gr32.gr_interface, &psin6->sin6_addr);

}



static int ipv6_set_opt_hdr(struct sock *sk, int optname, void __user *optval,

		int optlen)

{

	struct ipv6_pinfo *np = inet6_sk(sk);

	struct ipv6_opt_hdr *new = NULL;

	struct net *net = sock_net(sk);

	struct ipv6_txoptions *opt;

	int err;



	/* hop-by-hop / destination options are privileged option */

	if (optname != IPV6_RTHDR && !ns_capable(net->user_ns, CAP_NET_RAW))

		return -EPERM;



	/* remove any sticky options header with a zero option

	 * length, per RFC3542.

	 */

	if (optlen > 0) {

		if (!optval)

			return -EINVAL;

		if (optlen < sizeof(struct ipv6_opt_hdr) ||

		    optlen & 0x7 ||

		    optlen > 8 * 255)

			return -EINVAL;



		new = memdup_user(optval, optlen);

		if (IS_ERR(new))

			return PTR_ERR(new);

		if (unlikely(ipv6_optlen(new) > optlen)) {

			kfree(new);

			return -EINVAL;

		}

	}



	opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));

	opt = ipv6_renew_options(sk, opt, optname, new);

	kfree(new);

	if (IS_ERR(opt))

		return PTR_ERR(opt);



	/* routing header option needs extra check */

	err = -EINVAL;

	if (optname == IPV6_RTHDR && opt && opt->srcrt) {

		struct ipv6_rt_hdr *rthdr = opt->srcrt;

		switch (rthdr->type) {

#if IS_ENABLED(CONFIG_IPV6_MIP6)

		case IPV6_SRCRT_TYPE_2:

			if (rthdr->hdrlen != 2 || rthdr->segments_left != 1)

				goto sticky_done;

			break;

#endif

		case IPV6_SRCRT_TYPE_4:

		{

			struct ipv6_sr_hdr *srh =

				(struct ipv6_sr_hdr *)opt->srcrt;



			if (!seg6_validate_srh(srh, optlen, false))

				goto sticky_done;

			break;

		}

		default:

			goto sticky_done;

		}

	}



	err = 0;

	opt = ipv6_update_options(sk, opt);

sticky_done:

	if (opt) {

		atomic_sub(opt->tot_len, &sk->sk_omem_alloc);

		txopt_put(opt);

	}

	return err;

}



static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,

		    char __user *optval, unsigned int optlen)

{
@@ -580,82 +654,8 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname, 
	case IPV6_RTHDRDSTOPTS:

	case IPV6_RTHDR:

	case IPV6_DSTOPTS:

	{

		struct ipv6_txoptions *opt;

		struct ipv6_opt_hdr *new = NULL;



		/* hop-by-hop / destination options are privileged option */

		retv = -EPERM;

		if (optname != IPV6_RTHDR && !ns_capable(net->user_ns, CAP_NET_RAW))

			break;



		/* remove any sticky options header with a zero option

		 * length, per RFC3542.

		 */

		if (optlen == 0)

			optval = NULL;

		else if (!optval)

			goto e_inval;

		else if (optlen < sizeof(struct ipv6_opt_hdr) ||

			 optlen & 0x7 || optlen > 8 * 255)

			goto e_inval;

		else {

			new = memdup_user(optval, optlen);

			if (IS_ERR(new)) {

				retv = PTR_ERR(new);

				break;

			}

			if (unlikely(ipv6_optlen(new) > optlen)) {

				kfree(new);

				goto e_inval;

			}

		}



		opt = rcu_dereference_protected(np->opt,

						lockdep_sock_is_held(sk));

		opt = ipv6_renew_options(sk, opt, optname, new);

		kfree(new);

		if (IS_ERR(opt)) {

			retv = PTR_ERR(opt);

			break;

		}



		/* routing header option needs extra check */

		retv = -EINVAL;

		if (optname == IPV6_RTHDR && opt && opt->srcrt) {

			struct ipv6_rt_hdr *rthdr = opt->srcrt;

			switch (rthdr->type) {

#if IS_ENABLED(CONFIG_IPV6_MIP6)

			case IPV6_SRCRT_TYPE_2:

				if (rthdr->hdrlen != 2 ||

				    rthdr->segments_left != 1)

					goto sticky_done;



				break;

#endif

			case IPV6_SRCRT_TYPE_4:

			{

				struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)

							  opt->srcrt;



				if (!seg6_validate_srh(srh, optlen, false))

					goto sticky_done;

		retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);

		break;

			}

			default:

				goto sticky_done;

			}

		}



		retv = 0;

		opt = ipv6_update_options(sk, opt);

sticky_done:

		if (opt) {

			atomic_sub(opt->tot_len, &sk->sk_omem_alloc);

			txopt_put(opt);

		}

		break;

	}



	case IPV6_PKTINFO:

	{