Commit 168a2cca authored by Al Viro's avatar Al Viro
Browse files

ipv6: do compat setsockopt for MCAST_MSFILTER directly 



similar to the ipv4 counterpart of that patch - the same
trick used to align the tail array properly.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent d59eb177

net/ipv6/ipv6_sockglue.c

+47 −1
Original line number Diff line number Diff line
@@ -980,9 +980,55 @@ int compat_ipv6_setsockopt(struct sock *sk, int level, int optname, 
	case MCAST_LEAVE_SOURCE_GROUP:

	case MCAST_BLOCK_SOURCE:

	case MCAST_UNBLOCK_SOURCE:

	case MCAST_MSFILTER:

		return compat_mc_setsockopt(sk, level, optname, optval, optlen,

			ipv6_setsockopt);

	case MCAST_MSFILTER:

	{

		const int size0 = offsetof(struct compat_group_filter, gf_slist);

		struct compat_group_filter *gf32;

		void *p;

		int n;



		if (optlen < size0)

			return -EINVAL;

		if (optlen > sysctl_optmem_max - 4)

			return -ENOBUFS;



		p = kmalloc(optlen + 4, GFP_KERNEL);

		if (!p)

			return -ENOMEM;



		gf32 = p + 4; /* we want ->gf_group and ->gf_slist aligned */

		if (copy_from_user(gf32, optval, optlen)) {

			err = -EFAULT;

			goto mc_msf_out;

		}



		n = gf32->gf_numsrc;

		/* numsrc >= (4G-140)/128 overflow in 32 bits */

		if (n >= 0x1ffffffU ||

		    n > sysctl_mld_max_msf) {

			err = -ENOBUFS;

			goto mc_msf_out;

		}

		if (offsetof(struct compat_group_filter, gf_slist[n]) > optlen) {

			err = -EINVAL;

			goto mc_msf_out;

		}



		rtnl_lock();

		lock_sock(sk);

		err = ip6_mc_msfilter(sk, &(struct group_filter){

				.gf_interface = gf32->gf_interface,

				.gf_group = gf32->gf_group,

				.gf_fmode = gf32->gf_fmode,

				.gf_numsrc = gf32->gf_numsrc}, gf32->gf_slist);

		release_sock(sk);

		rtnl_unlock();

mc_msf_out:

		kfree(p);

		return err;

	}

	}



	err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);