mptcp: setsockopt: handle SOL_SOCKET in one place only

Move the pre-check to the function that handles all SOL_SOCKET values.

At this point there is complete coverage for all values that were
accepted by the pre-check.

BUSYPOLL functions are accepted but will not have any functionality
yet until its clear how the expected mptcp behaviour should look like.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index 3168ad4..092d1f6 100644 (file)
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -304,6 +304,14 @@ static int mptcp_setsockopt_sol_socket(struct mptcp_sock *msk, int optname,
                return mptcp_setsockopt_sol_socket_int(msk, optname, optval, optlen);
        case SO_LINGER:
                return mptcp_setsockopt_sol_socket_linger(msk, optval, optlen);
+       case SO_RCVLOWAT:
+       case SO_RCVTIMEO_OLD:
+       case SO_RCVTIMEO_NEW:
+       case SO_BUSY_POLL:
+       case SO_PREFER_BUSY_POLL:
+       case SO_BUSY_POLL_BUDGET:
+               /* No need to copy: only relevant for msk */
+               return sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, optval, optlen);
        case SO_NO_CHECK:
        case SO_DONTROUTE:
        case SO_BROADCAST:
@@ -317,7 +325,24 @@ static int mptcp_setsockopt_sol_socket(struct mptcp_sock *msk, int optname,
                return 0;
        }
 
-       return sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, optval, optlen);
+       /* SO_OOBINLINE is not supported, let's avoid the related mess
+        * SO_ATTACH_FILTER, SO_ATTACH_BPF, SO_ATTACH_REUSEPORT_CBPF,
+        * SO_DETACH_REUSEPORT_BPF, SO_DETACH_FILTER, SO_LOCK_FILTER,
+        * we must be careful with subflows
+        *
+        * SO_ATTACH_REUSEPORT_EBPF is not supported, at it checks
+        * explicitly the sk_protocol field
+        *
+        * SO_PEEK_OFF is unsupported, as it is for plain TCP
+        * SO_MAX_PACING_RATE is unsupported, we must be careful with subflows
+        * SO_CNX_ADVICE is currently unsupported, could possibly be relevant,
+        * but likely needs careful design
+        *
+        * SO_ZEROCOPY is currently unsupported, TODO in sndmsg
+        * SO_TXTIME is currently unsupported
+        */
+
+       return -EOPNOTSUPP;
 }
 
 static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname,
@@ -349,72 +374,6 @@ static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname,
 
 static bool mptcp_supported_sockopt(int level, int optname)
 {
-       if (level == SOL_SOCKET) {
-               switch (optname) {
-               case SO_DEBUG:
-               case SO_REUSEPORT:
-               case SO_REUSEADDR:
-
-               /* the following ones need a better implementation,
-                * but are quite common we want to preserve them
-                */
-               case SO_BINDTODEVICE:
-               case SO_SNDBUF:
-               case SO_SNDBUFFORCE:
-               case SO_RCVBUF:
-               case SO_RCVBUFFORCE:
-               case SO_KEEPALIVE:
-               case SO_PRIORITY:
-               case SO_LINGER:
-               case SO_TIMESTAMP_OLD:
-               case SO_TIMESTAMP_NEW:
-               case SO_TIMESTAMPNS_OLD:
-               case SO_TIMESTAMPNS_NEW:
-               case SO_TIMESTAMPING_OLD:
-               case SO_TIMESTAMPING_NEW:
-               case SO_RCVLOWAT:
-               case SO_RCVTIMEO_OLD:
-               case SO_RCVTIMEO_NEW:
-               case SO_SNDTIMEO_OLD:
-               case SO_SNDTIMEO_NEW:
-               case SO_MARK:
-               case SO_INCOMING_CPU:
-               case SO_BINDTOIFINDEX:
-               case SO_BUSY_POLL:
-               case SO_PREFER_BUSY_POLL:
-               case SO_BUSY_POLL_BUDGET:
-
-               /* next ones are no-op for plain TCP */
-               case SO_NO_CHECK:
-               case SO_DONTROUTE:
-               case SO_BROADCAST:
-               case SO_BSDCOMPAT:
-               case SO_PASSCRED:
-               case SO_PASSSEC:
-               case SO_RXQ_OVFL:
-               case SO_WIFI_STATUS:
-               case SO_NOFCS:
-               case SO_SELECT_ERR_QUEUE:
-                       return true;
-               }
-
-               /* SO_OOBINLINE is not supported, let's avoid the related mess */
-               /* SO_ATTACH_FILTER, SO_ATTACH_BPF, SO_ATTACH_REUSEPORT_CBPF,
-                * SO_DETACH_REUSEPORT_BPF, SO_DETACH_FILTER, SO_LOCK_FILTER,
-                * we must be careful with subflows
-                */
-               /* SO_ATTACH_REUSEPORT_EBPF is not supported, at it checks
-                * explicitly the sk_protocol field
-                */
-               /* SO_PEEK_OFF is unsupported, as it is for plain TCP */
-               /* SO_MAX_PACING_RATE is unsupported, we must be careful with subflows */
-               /* SO_CNX_ADVICE is currently unsupported, could possibly be relevant,
-                * but likely needs careful design
-                */
-               /* SO_ZEROCOPY is currently unsupported, TODO in sndmsg */
-               /* SO_TXTIME is currently unsupported */
-               return false;
-       }
        if (level == SOL_IP) {
                switch (optname) {
                /* should work fine */
@@ -624,12 +583,12 @@ int mptcp_setsockopt(struct sock *sk, int level, int optname,
 
        pr_debug("msk=%p", msk);
 
-       if (!mptcp_supported_sockopt(level, optname))
-               return -ENOPROTOOPT;
-
        if (level == SOL_SOCKET)
                return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen);
 
+       if (!mptcp_supported_sockopt(level, optname))
+               return -ENOPROTOOPT;
+
        /* @@ the meaning of setsockopt() when the socket is connected and
         * there are multiple subflows is not yet defined. It is up to the
         * MPTCP-level socket to configure the subflows until the subflow