From: David Howells dhowells@redhat.com
[ Upstream commit 5273a191dca65a675dc0bcf3909e59c6933e2831 ]
When a call is disconnected, the connection pointer from the call is cleared to make sure it isn't used again and to prevent further attempted transmission for the call. Unfortunately, there might be a daemon trying to use it at the same time to transmit a packet.
Fix this by keeping call->conn set, but setting a flag on the call to indicate disconnection instead.
Remove also the bits in the transmission functions where the conn pointer is checked and a ref taken under spinlock as this is now redundant.
Fixes: 8d94aa381dab ("rxrpc: Calls shouldn't hold socket refs") Signed-off-by: David Howells dhowells@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/rxrpc/ar-internal.h | 1 + net/rxrpc/call_object.c | 4 ++-- net/rxrpc/conn_client.c | 3 +-- net/rxrpc/conn_object.c | 4 ++-- net/rxrpc/output.c | 26 +++++++++----------------- 5 files changed, 15 insertions(+), 23 deletions(-)
--- a/net/rxrpc/ar-internal.h +++ b/net/rxrpc/ar-internal.h @@ -451,6 +451,7 @@ enum rxrpc_call_flag { RXRPC_CALL_SEND_PING, /* A ping will need to be sent */ RXRPC_CALL_PINGING, /* Ping in process */ RXRPC_CALL_RETRANS_TIMEOUT, /* Retransmission due to timeout occurred */ + RXRPC_CALL_DISCONNECTED, /* The call has been disconnected */ };
/* --- a/net/rxrpc/call_object.c +++ b/net/rxrpc/call_object.c @@ -505,7 +505,7 @@ void rxrpc_release_call(struct rxrpc_soc
_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
- if (conn) + if (conn && !test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) rxrpc_disconnect_call(call);
for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) { @@ -639,6 +639,7 @@ static void rxrpc_rcu_destroy_call(struc { struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
+ rxrpc_put_connection(call->conn); rxrpc_put_peer(call->peer); kfree(call->rxtx_buffer); kfree(call->rxtx_annotations); @@ -660,7 +661,6 @@ void rxrpc_cleanup_call(struct rxrpc_cal
ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE); ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags)); - ASSERTCMP(call->conn, ==, NULL);
/* Clean up the Rx/Tx buffer */ for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) --- a/net/rxrpc/conn_client.c +++ b/net/rxrpc/conn_client.c @@ -762,9 +762,9 @@ void rxrpc_disconnect_client_call(struct struct rxrpc_net *rxnet = rxrpc_net(sock_net(&call->socket->sk));
trace_rxrpc_client(conn, channel, rxrpc_client_chan_disconnect); - call->conn = NULL;
spin_lock(&conn->channel_lock); + set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
/* Calls that have never actually been assigned a channel can simply be * discarded. If the conn didn't get used either, it will follow @@ -863,7 +863,6 @@ out: spin_unlock(&rxnet->client_conn_cache_lock); out_2: spin_unlock(&conn->channel_lock); - rxrpc_put_connection(conn); _leave(""); return;
--- a/net/rxrpc/conn_object.c +++ b/net/rxrpc/conn_object.c @@ -163,6 +163,8 @@ void __rxrpc_disconnect_call(struct rxrp
_enter("%d,%x", conn->debug_id, call->cid);
+ set_bit(RXRPC_CALL_DISCONNECTED, &call->flags); + if (rcu_access_pointer(chan->call) == call) { /* Save the result of the call so that we can repeat it if necessary * through the channel, whilst disposing of the actual call record. @@ -207,9 +209,7 @@ void rxrpc_disconnect_call(struct rxrpc_ __rxrpc_disconnect_call(conn, call); spin_unlock(&conn->channel_lock);
- call->conn = NULL; conn->idle_timestamp = jiffies; - rxrpc_put_connection(conn); }
/* --- a/net/rxrpc/output.c +++ b/net/rxrpc/output.c @@ -96,7 +96,7 @@ static size_t rxrpc_fill_out_ack(struct */ int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping) { - struct rxrpc_connection *conn = NULL; + struct rxrpc_connection *conn; struct rxrpc_ack_buffer *pkt; struct msghdr msg; struct kvec iov[2]; @@ -106,18 +106,14 @@ int rxrpc_send_ack_packet(struct rxrpc_c int ret; u8 reason;
- spin_lock_bh(&call->lock); - if (call->conn) - conn = rxrpc_get_connection_maybe(call->conn); - spin_unlock_bh(&call->lock); - if (!conn) + if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) return -ECONNRESET;
pkt = kzalloc(sizeof(*pkt), GFP_KERNEL); - if (!pkt) { - rxrpc_put_connection(conn); + if (!pkt) return -ENOMEM; - } + + conn = call->conn;
msg.msg_name = &call->peer->srx.transport; msg.msg_namelen = call->peer->srx.transport_len; @@ -204,7 +200,6 @@ int rxrpc_send_ack_packet(struct rxrpc_c }
out: - rxrpc_put_connection(conn); kfree(pkt); return ret; } @@ -214,20 +209,18 @@ out: */ int rxrpc_send_abort_packet(struct rxrpc_call *call) { - struct rxrpc_connection *conn = NULL; + struct rxrpc_connection *conn; struct rxrpc_abort_buffer pkt; struct msghdr msg; struct kvec iov[1]; rxrpc_serial_t serial; int ret;
- spin_lock_bh(&call->lock); - if (call->conn) - conn = rxrpc_get_connection_maybe(call->conn); - spin_unlock_bh(&call->lock); - if (!conn) + if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) return -ECONNRESET;
+ conn = call->conn; + msg.msg_name = &call->peer->srx.transport; msg.msg_namelen = call->peer->srx.transport_len; msg.msg_control = NULL; @@ -255,7 +248,6 @@ int rxrpc_send_abort_packet(struct rxrpc ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 1, sizeof(pkt));
- rxrpc_put_connection(conn); return ret; }