diff options
| author | David Howells <dhowells@redhat.com> | 2017-03-04 03:01:41 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-03-08 00:59:06 +0300 |
| commit | 146d8fef9da1ba854de7fa28b9cb9eb147535f88 (patch) | |
| tree | 76b9bea4ac0c4bcd1a2c50418a304007b54ad6bd /net/rxrpc/input.c | |
| parent | 02b2faaf0af1d85585f6d6980e286d53612acfc2 (diff) | |
| download | linux-146d8fef9da1ba854de7fa28b9cb9eb147535f88.tar.xz | |
rxrpc: Call state should be read with READ_ONCE() under some circumstances
The call state may be changed at any time by the data-ready routine in
response to received packets, so if the call state is to be read and acted
upon several times in a function, READ_ONCE() must be used unless the call
state lock is held.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/rxrpc/input.c')
| -rw-r--r-- | net/rxrpc/input.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c index 9f4cfa25af7c..d74921c4969b 100644 --- a/net/rxrpc/input.c +++ b/net/rxrpc/input.c @@ -420,6 +420,7 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb, u16 skew) { struct rxrpc_skb_priv *sp = rxrpc_skb(skb); + enum rxrpc_call_state state; unsigned int offset = sizeof(struct rxrpc_wire_header); unsigned int ix; rxrpc_serial_t serial = sp->hdr.serial, ack_serial = 0; @@ -434,14 +435,15 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb, _proto("Rx DATA %%%u { #%u f=%02x }", sp->hdr.serial, seq, sp->hdr.flags); - if (call->state >= RXRPC_CALL_COMPLETE) + state = READ_ONCE(call->state); + if (state >= RXRPC_CALL_COMPLETE) return; /* Received data implicitly ACKs all of the request packets we sent * when we're acting as a client. */ - if ((call->state == RXRPC_CALL_CLIENT_SEND_REQUEST || - call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY) && + if ((state == RXRPC_CALL_CLIENT_SEND_REQUEST || + state == RXRPC_CALL_CLIENT_AWAIT_REPLY) && !rxrpc_receiving_reply(call)) return; @@ -799,7 +801,7 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb, return rxrpc_proto_abort("AK0", call, 0); /* Ignore ACKs unless we are or have just been transmitting. */ - switch (call->state) { + switch (READ_ONCE(call->state)) { case RXRPC_CALL_CLIENT_SEND_REQUEST: case RXRPC_CALL_CLIENT_AWAIT_REPLY: case RXRPC_CALL_SERVER_SEND_REPLY: @@ -940,7 +942,7 @@ static void rxrpc_input_call_packet(struct rxrpc_call *call, static void rxrpc_input_implicit_end_call(struct rxrpc_connection *conn, struct rxrpc_call *call) { - switch (call->state) { + switch (READ_ONCE(call->state)) { case RXRPC_CALL_SERVER_AWAIT_ACK: rxrpc_call_completed(call); break; |