net/ipv4: factor out MCAST_MSFILTER setsockopt helpers

Factor out one helper each for setting the native and compat
version of the MCAST_MSFILTER option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 70d32c9476a2e314b0d1917388ca4d741004ca39..b587dee006f8828c69436c4d82e7388c8a6829f5 100644 (file)
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -722,6 +722,90 @@ static int do_mcast_group_source(struct sock *sk, int optname,
        return ip_mc_source(add, omode, sk, &mreqs, greqs->gsr_interface);
 }
 
+static int ip_set_mcast_msfilter(struct sock *sk, void __user *optval,
+               int optlen)
+{
+       struct group_filter *gsf = NULL;
+       int err;
+
+       if (optlen < GROUP_FILTER_SIZE(0))
+               return -EINVAL;
+       if (optlen > sysctl_optmem_max)
+               return -ENOBUFS;
+
+       gsf = memdup_user(optval, optlen);
+       if (IS_ERR(gsf))
+               return PTR_ERR(gsf);
+
+       /* numsrc >= (4G-140)/128 overflow in 32 bits */
+       err = -ENOBUFS;
+       if (gsf->gf_numsrc >= 0x1ffffff ||
+           gsf->gf_numsrc > sock_net(sk)->ipv4.sysctl_igmp_max_msf)
+               goto out_free_gsf;
+
+       err = -EINVAL;
+       if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
+               goto out_free_gsf;
+
+       err = set_mcast_msfilter(sk, gsf->gf_interface, gsf->gf_numsrc,
+                                gsf->gf_fmode, &gsf->gf_group, gsf->gf_slist);
+out_free_gsf:
+       kfree(gsf);
+       return err;
+}
+
+#ifdef CONFIG_COMPAT
+static int compat_ip_set_mcast_msfilter(struct sock *sk, void __user *optval,
+               int optlen)
+{
+       const int size0 = offsetof(struct compat_group_filter, gf_slist);
+       struct compat_group_filter *gf32;
+       unsigned int n;
+       void *p;
+       int err;
+
+       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 */
+
+       err = -EFAULT;
+       if (copy_from_user(gf32, optval, optlen))
+               goto out_free_gsf;
+
+       /* numsrc >= (4G-140)/128 overflow in 32 bits */
+       n = gf32->gf_numsrc;
+       err = -ENOBUFS;
+       if (n >= 0x1ffffff)
+               goto out_free_gsf;
+
+       err = -EINVAL;
+       if (offsetof(struct compat_group_filter, gf_slist[n]) > optlen)
+               goto out_free_gsf;
+
+       rtnl_lock();
+       lock_sock(sk);
+
+       /* numsrc >= (4G-140)/128 overflow in 32 bits */
+       err = -ENOBUFS;
+       if (n > sock_net(sk)->ipv4.sysctl_igmp_max_msf)
+               goto out_unlock;
+       err = set_mcast_msfilter(sk, gf32->gf_interface, n, gf32->gf_fmode,
+                                &gf32->gf_group, gf32->gf_slist);
+out_unlock:
+       release_sock(sk);
+       rtnl_unlock();
+out_free_gsf:
+       kfree(p);
+       return err;
+}
+#endif
+
 static int do_ip_setsockopt(struct sock *sk, int level,
                            int optname, char __user *optval, unsigned int optlen)
 {
@@ -1167,37 +1251,8 @@ static int do_ip_setsockopt(struct sock *sk, int level,
                break;
        }
        case MCAST_MSFILTER:
-       {
-               struct group_filter *gsf = NULL;
-
-               if (optlen < GROUP_FILTER_SIZE(0))
-                       goto e_inval;
-               if (optlen > sysctl_optmem_max) {
-                       err = -ENOBUFS;
-                       break;
-               }
-               gsf = memdup_user(optval, optlen);
-               if (IS_ERR(gsf)) {
-                       err = PTR_ERR(gsf);
-                       break;
-               }
-               /* numsrc >= (4G-140)/128 overflow in 32 bits */
-               if (gsf->gf_numsrc >= 0x1ffffff ||
-                   gsf->gf_numsrc > net->ipv4.sysctl_igmp_max_msf) {
-                       err = -ENOBUFS;
-                       goto mc_msf_out;
-               }
-               if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
-                       err = -EINVAL;
-                       goto mc_msf_out;
-               }
-               err = set_mcast_msfilter(sk, gsf->gf_interface,
-                                        gsf->gf_numsrc, gsf->gf_fmode,
-                                        &gsf->gf_group, gsf->gf_slist);
-mc_msf_out:
-               kfree(gsf);
+               err = ip_set_mcast_msfilter(sk, optval, optlen);
                break;
-       }
        case IP_MULTICAST_ALL:
                if (optlen < 1)
                        goto e_inval;
@@ -1391,52 +1446,7 @@ int compat_ip_setsockopt(struct sock *sk, int level, int optname,
                return err;
        }
        case MCAST_MSFILTER:
-       {
-               const int size0 = offsetof(struct compat_group_filter, gf_slist);
-               struct compat_group_filter *gf32;
-               unsigned int n;
-               void *p;
-
-               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 >= 0x1ffffff) {
-                       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);
-               /* numsrc >= (4G-140)/128 overflow in 32 bits */
-               if (n > sock_net(sk)->ipv4.sysctl_igmp_max_msf)
-                       err = -ENOBUFS;
-               else
-                       err = set_mcast_msfilter(sk, gf32->gf_interface,
-                                                n, gf32->gf_fmode,
-                                                &gf32->gf_group, gf32->gf_slist);
-               release_sock(sk);
-               rtnl_unlock();
-mc_msf_out:
-               kfree(p);
-               return err;
-       }
+               return compat_ip_set_mcast_msfilter(sk, optval, optlen);
        }
 
        err = do_ip_setsockopt(sk, level, optname, optval, optlen);