BMC/Intel-BMC/linux.git/net/rxrpc/ar-input.c, branch dev-4.6

rxrpc: Be more selective about the types of received packets we accept

2016-03-04T15:56:06+00:00

Currently, received RxRPC packets outside the range 1-13 are rejected. There are, however, holes in the range that should also be rejected - plus at least one type we don't yet support - so reject these also. Signed-off-by: David Howells

rxrpc: Keep the skb private record of the Rx header in host byte order

2016-03-04T15:53:46+00:00

Currently, a copy of the Rx packet header is copied into the the sk_buff private data so that we can advance the pointer into the buffer, potentially discarding the original. At the moment, this copy is held in network byte order, but this means we're doing a lot of unnecessary translations. The reasons it was done this way are that we need the values in network byte order occasionally and we can use the copy, slightly modified, as part of an iov array when sending an ack or an abort packet. However, it seems more reasonable on review that it would be better kept in host byte order and that we make up a new header when we want to send another packet. To this end, rename the original header struct to rxrpc_wire_header (with BE fields) and institute a variant called rxrpc_host_header that has host order fields. Change the struct in the sk_buff private data into an rxrpc_host_header and translate the values when filling it in. This further allows us to keep values kept in various structures in host byte order rather than network byte order and allows removal of some fields that are byteswapped duplicates. Signed-off-by: David Howells

rxrpc: Rename call events to begin RXRPC_CALL_EV_

2016-03-04T15:53:46+00:00

Rename call event names to begin RXRPC_CALL_EV_ to distinguish them from the flags. Signed-off-by: David Howells

RxRPC: Handle VERSION Rx protocol packets

2015-04-01T15:31:26+00:00

Handle VERSION Rx protocol packets. We should respond to a VERSION packet with a string indicating the Rx version. This is a maximum of 64 characters and is padded out to 65 chars with NUL bytes. Note that other AFS clients use the version request as a NAT keepalive so we need to handle it rather than returning an abort. The standard formulation seems to be: built --

for example: " OpenAFS 1.6.2 built 2013-05-07 " (note the three extra spaces) as obtained with: rxdebug grand.mit.edu -version from the openafs package. Signed-off-by: David Howells

net: remove dead code after sk_data_ready change

2014-08-23T04:08:50+00:00

As a followup to commit 676d23690fb ("net: Fix use after free by removing length arg from sk_data_ready callbacks"), we can remove some useless code in sock_queue_rcv_skb() and rxrpc_queue_rcv_skb() Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

net: Fix use after free by removing length arg from sk_data_ready callbacks.

2014-04-11T20:15:36+00:00

Several spots in the kernel perform a sequence like: skb_queue_tail(&sk->s_receive_queue, skb); sk->sk_data_ready(sk, skb->len); But at the moment we place the SKB onto the socket receive queue it can be consumed and freed up. So this skb->len access is potentially to freed up memory. Furthermore, the skb->len can be modified by the consumer so it is possible that the value isn't accurate. And finally, no actual implementation of this callback actually uses the length argument. And since nobody actually cared about it's value, lots of call sites pass arbitrary values in such as '0' and even '1'. So just remove the length argument from the callback, that way there is no confusion whatsoever and all of these use-after-free cases get fixed as a side effect. Based upon a patch by Eric Dumazet and his suggestion to audit this issue tree-wide. Signed-off-by: David S. Miller

af_rxrpc: Keep rxrpc_call pointers in a hashtable

2014-03-04T10:36:53+00:00

Keep track of rxrpc_call structures in a hashtable so they can be found directly from the network parameters which define the call. This allows incoming packets to be routed directly to a call without walking through hierarchy of peer -> transport -> connection -> call and all the spinlocks that that entailed. Signed-off-by: Tim Smith Signed-off-by: David Howells

af_rxrpc: Improve ACK production

2014-02-26T17:25:07+00:00

Improve ACK production by the following means: (1) Don't send an ACK_REQUESTED ack immediately even if the RXRPC_MORE_PACKETS flag isn't set on a data packet that has also has RXRPC_REQUEST_ACK set. MORE_PACKETS just means that the sender just emptied its Tx data buffer. More data will be forthcoming unless RXRPC_LAST_PACKET is also flagged. It is possible to see runs of DATA packets with MORE_PACKETS unset that aren't waiting for an ACK. It is therefore better to wait a small instant to see if we can combine an ACK for several packets. (2) Don't send an ACK_IDLE ack immediately unless we're responding to the terminal data packet of a call. Whilst sending an ACK_IDLE mid-call serves to let the other side know that we won't be asking it to resend certain Tx buffers and that it can discard them, spamming it with loads of acks just because we've temporarily run out of data just distracts it. (3) Put the ACK_IDLE ack generation timeout up to half a second rather than a single jiffy. Just because we haven't been given more data immediately doesn't mean that more isn't forthcoming. The other side may be busily finding the data to send to us. Signed-off-by: David Howells

af_rxrpc: Add sysctls for configuring RxRPC parameters

2014-02-26T17:25:06+00:00

Add sysctls for configuring RxRPC protocol handling, specifically controls on delays before ack generation, the delay before resending a packet, the maximum lifetime of a call and the expiration times of calls, connections and transports that haven't been recently used. More info added in Documentation/networking/rxrpc.txt. Signed-off-by: David Howells

af_rxrpc: Prevent RxRPC peers from ABORT-storming one another

2014-02-07T18:58:43+00:00

When an ABORT is sent, aborting a connection, the sender quite reasonably forgets about the connection. If another frame is received, another ABORT will be sent. When the receiver gets it, it no longer applies to an extant connection, so an ABORT is sent, and so on... Prevent this by never sending a rejection for an ABORT packet. Signed-off-by: Tim Smith Signed-off-by: David Howells