net/ipv6: factor out MCAST_MSFILTER getsockopt helpers
authorChristoph Hellwig <hch@lst.de>
Fri, 17 Jul 2020 06:23:27 +0000 (08:23 +0200)
committerDavid S. Miller <davem@davemloft.net>
Mon, 20 Jul 2020 01:16:41 +0000 (18:16 -0700)
Factor out one helper each for getting 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>
net/ipv6/ipv6_sockglue.c

index 6adfbdc..ef5656f 100644 (file)
@@ -1071,6 +1071,77 @@ static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
        return len;
 }
 
+static int ipv6_get_msfilter(struct sock *sk, void __user *optval,
+               int __user *optlen, int len)
+{
+       const int size0 = offsetof(struct group_filter, gf_slist);
+       struct group_filter __user *p = optval;
+       struct group_filter gsf;
+       int num;
+       int err;
+
+       if (len < size0)
+               return -EINVAL;
+       if (copy_from_user(&gsf, p, size0))
+               return -EFAULT;
+       if (gsf.gf_group.ss_family != AF_INET6)
+               return -EADDRNOTAVAIL;
+       num = gsf.gf_numsrc;
+       lock_sock(sk);
+       err = ip6_mc_msfget(sk, &gsf, p->gf_slist);
+       if (!err) {
+               if (num > gsf.gf_numsrc)
+                       num = gsf.gf_numsrc;
+               if (put_user(GROUP_FILTER_SIZE(num), optlen) ||
+                   copy_to_user(p, &gsf, size0))
+                       err = -EFAULT;
+       }
+       release_sock(sk);
+       return err;
+}
+
+#ifdef CONFIG_COMPAT
+static int compat_ipv6_get_msfilter(struct sock *sk, void __user *optval,
+               int __user *optlen)
+{
+       const int size0 = offsetof(struct compat_group_filter, gf_slist);
+       struct compat_group_filter __user *p = optval;
+       struct compat_group_filter gf32;
+       struct group_filter gf;
+       int len, err;
+       int num;
+
+       if (get_user(len, optlen))
+               return -EFAULT;
+       if (len < size0)
+               return -EINVAL;
+
+       if (copy_from_user(&gf32, p, size0))
+               return -EFAULT;
+       gf.gf_interface = gf32.gf_interface;
+       gf.gf_fmode = gf32.gf_fmode;
+       num = gf.gf_numsrc = gf32.gf_numsrc;
+       gf.gf_group = gf32.gf_group;
+
+       if (gf.gf_group.ss_family != AF_INET6)
+               return -EADDRNOTAVAIL;
+
+       lock_sock(sk);
+       err = ip6_mc_msfget(sk, &gf, p->gf_slist);
+       release_sock(sk);
+       if (err)
+               return err;
+       if (num > gf.gf_numsrc)
+               num = gf.gf_numsrc;
+       len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
+       if (put_user(len, optlen) ||
+           put_user(gf.gf_fmode, &p->gf_fmode) ||
+           put_user(gf.gf_numsrc, &p->gf_numsrc))
+               return -EFAULT;
+       return 0;
+}
+#endif
+
 static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
                    char __user *optval, int __user *optlen, unsigned int flags)
 {
@@ -1094,33 +1165,7 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
                val = sk->sk_family;
                break;
        case MCAST_MSFILTER:
-       {
-               struct group_filter __user *p = (void __user *)optval;
-               struct group_filter gsf;
-               const int size0 = offsetof(struct group_filter, gf_slist);
-               int num;
-               int err;
-
-               if (len < size0)
-                       return -EINVAL;
-               if (copy_from_user(&gsf, p, size0))
-                       return -EFAULT;
-               if (gsf.gf_group.ss_family != AF_INET6)
-                       return -EADDRNOTAVAIL;
-               num = gsf.gf_numsrc;
-               lock_sock(sk);
-               err = ip6_mc_msfget(sk, &gsf, p->gf_slist);
-               if (!err) {
-                       if (num > gsf.gf_numsrc)
-                               num = gsf.gf_numsrc;
-                       if (put_user(GROUP_FILTER_SIZE(num), optlen) ||
-                           copy_to_user(p, &gsf, size0))
-                               err = -EFAULT;
-               }
-               release_sock(sk);
-               return err;
-       }
-
+               return ipv6_get_msfilter(sk, optval, optlen, len);
        case IPV6_2292PKTOPTIONS:
        {
                struct msghdr msg;
@@ -1481,44 +1526,8 @@ int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
        if (level != SOL_IPV6)
                return -ENOPROTOOPT;
 
-       if (optname == MCAST_MSFILTER) {
-               const int size0 = offsetof(struct compat_group_filter, gf_slist);
-               struct compat_group_filter __user *p = (void __user *)optval;
-               struct compat_group_filter gf32;
-               struct group_filter gf;
-               int ulen, err;
-               int num;
-
-               if (get_user(ulen, optlen))
-                       return -EFAULT;
-
-               if (ulen < size0)
-                       return -EINVAL;
-
-               if (copy_from_user(&gf32, p, size0))
-                       return -EFAULT;
-
-               gf.gf_interface = gf32.gf_interface;
-               gf.gf_fmode = gf32.gf_fmode;
-               num = gf.gf_numsrc = gf32.gf_numsrc;
-               gf.gf_group = gf32.gf_group;
-
-               if (gf.gf_group.ss_family != AF_INET6)
-                       return -EADDRNOTAVAIL;
-               lock_sock(sk);
-               err = ip6_mc_msfget(sk, &gf, p->gf_slist);
-               release_sock(sk);
-               if (err)
-                       return err;
-               if (num > gf.gf_numsrc)
-                       num = gf.gf_numsrc;
-               ulen = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
-               if (put_user(ulen, optlen) ||
-                   put_user(gf.gf_fmode, &p->gf_fmode) ||
-                   put_user(gf.gf_numsrc, &p->gf_numsrc))
-                       return -EFAULT;
-               return 0;
-       }
+       if (optname == MCAST_MSFILTER)
+               return compat_ipv6_get_msfilter(sk, optval, optlen);
 
        err = do_ipv6_getsockopt(sk, level, optname, optval, optlen,
                                 MSG_CMSG_COMPAT);