1 files changed, 33 insertions, 16 deletions

diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index 1edf2cf62cc5..8b8d7e14f800 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -134,6 +134,8 @@ static void rxrpc_end_rx_phase(struct rxrpc_call *call)
 {
         _enter("%d,%s", call->debug_id, rxrpc_call_states[call->state]);
 
+        ASSERTCMP(call->rx_hard_ack, ==, call->rx_top);
+
         if (call->state == RXRPC_CALL_CLIENT_RECV_REPLY) {
                 rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, 0, true, false);
                 rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ACK);
@@ -163,8 +165,10 @@ static void rxrpc_end_rx_phase(struct rxrpc_call *call)
  */
 static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
 {
+        struct rxrpc_skb_priv *sp;
         struct sk_buff *skb;
         rxrpc_seq_t hard_ack, top;
+        u8 flags;
         int ix;
 
         _enter("%d", call->debug_id);
@@ -177,6 +181,8 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
         ix = hard_ack & RXRPC_RXTX_BUFF_MASK;
         skb = call->rxtx_buffer[ix];
         rxrpc_see_skb(skb);
+        sp = rxrpc_skb(skb);
+        flags = sp->hdr.flags;
         call->rxtx_buffer[ix] = NULL;
         call->rxtx_annotations[ix] = 0;
         /* Barrier against rxrpc_input_data(). */
@@ -184,8 +190,8 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
 
         rxrpc_free_skb(skb);
 
-        _debug("%u,%u,%lx", hard_ack, top, call->flags);
-        if (hard_ack == top && test_bit(RXRPC_CALL_RX_LAST, &call->flags))
+        _debug("%u,%u,%02x", hard_ack, top, flags);
+        if (flags & RXRPC_LAST_PACKET)
                 rxrpc_end_rx_phase(call);
 }
 
@@ -278,13 +284,19 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
         size_t remain;
         bool last;
         unsigned int rx_pkt_offset, rx_pkt_len;
-        int ix, copy, ret = 0;
+        int ix, copy, ret = -EAGAIN, ret2;
 
         _enter("");
 
         rx_pkt_offset = call->rx_pkt_offset;
         rx_pkt_len = call->rx_pkt_len;
 
+        if (call->state >= RXRPC_CALL_SERVER_ACK_REQUEST) {
+                seq = call->rx_hard_ack;
+                ret = 1;
+                goto done;
+        }
+
         /* Barriers against rxrpc_input_data(). */
         hard_ack = call->rx_hard_ack;
         top = smp_load_acquire(&call->rx_top);
@@ -301,11 +313,13 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
                         sock_recv_timestamp(msg, sock->sk, skb);
 
                 if (rx_pkt_offset == 0) {
-                        ret = rxrpc_locate_data(call, skb,
-                                                &call->rxtx_annotations[ix],
-                                                &rx_pkt_offset, &rx_pkt_len);
-                        if (ret < 0)
+                        ret2 = rxrpc_locate_data(call, skb,
+                                                 &call->rxtx_annotations[ix],
+                                                 &rx_pkt_offset, &rx_pkt_len);
+                        if (ret2 < 0) {
+                                ret = ret2;
                                 goto out;
+                        }
                 }
                 _debug("recvmsg %x DATA #%u { %d, %d }",
                        sp->hdr.callNumber, seq, rx_pkt_offset, rx_pkt_len);
@@ -316,10 +330,12 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
                 if (copy > remain)
                         copy = remain;
                 if (copy > 0) {
-                        ret = skb_copy_datagram_iter(skb, rx_pkt_offset, iter,
-                                                     copy);
-                        if (ret < 0)
+                        ret2 = skb_copy_datagram_iter(skb, rx_pkt_offset, iter,
+                                                      copy);
+                        if (ret2 < 0) {
+                                ret = ret2;
                                 goto out;
+                        }
 
                         /* handle piecemeal consumption of data packets */
                         _debug("copied %d @%zu", copy, *_offset);
@@ -332,6 +348,7 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
                 if (rx_pkt_len > 0) {
                         _debug("buffer full");
                         ASSERTCMP(*_offset, ==, len);
+                        ret = 0;
                         break;
                 }
 
@@ -342,19 +359,19 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
                 rx_pkt_offset = 0;
                 rx_pkt_len = 0;
 
-                ASSERTIFCMP(last, seq, ==, top);
-        }
-
-        if (after(seq, top)) {
-                ret = -EAGAIN;
-                if (test_bit(RXRPC_CALL_RX_LAST, &call->flags))
+                if (last) {
+                        ASSERTCMP(seq, ==, READ_ONCE(call->rx_top));
                         ret = 1;
+                        goto out;
+                }
         }
+
 out:
         if (!(flags & MSG_PEEK)) {
                 call->rx_pkt_offset = rx_pkt_offset;
                 call->rx_pkt_len = rx_pkt_len;
         }
+done:
         _leave(" = %d [%u/%u]", ret, seq, top);
         return ret;
 }