linux/net/tipc/socket.c, branch v4.3

tipc: clean up socket layer message reception

2015-07-26T23:31:50Z

When a message is received in a socket, one of the call chains tipc_sk_rcv()->tipc_sk_enqueue()->filter_rcv()(->tipc_sk_proto_rcv()) or tipc_sk_backlog_rcv()->filter_rcv()(->tipc_sk_proto_rcv()) are followed. At each of these levels we may encounter situations where the message may need to be rejected, or a new message produced for transfer back to the sender. Despite recent improvements, the current code for doing this is perceived as awkward and hard to follow. Leveraging the two previous commits in this series, we now introduce a more uniform handling of such situations. We let each of the functions in the chain itself produce/reverse the message to be returned to the sender, but also perform the actual forwarding. This simplifies the necessary logics within each function. Reviewed-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: introduce new tipc_sk_respond() function

2015-07-26T23:31:50Z

Currently, we use the code sequence if (msg_reverse()) tipc_link_xmit_skb() at numerous locations in socket.c. The preparation of arguments for these calls, as well as the sequence itself, makes the code unecessarily complex. In this commit, we introduce a new function, tipc_sk_respond(), that performs this call combination. We also replace some, but not yet all, of these explicit call sequences with calls to the new function. Notably, we let the function tipc_sk_proto_rcv() use the new function to directly send out PROBE_REPLY messages, instead of deferring this to the calling tipc_sk_rcv() function, as we do now. Reviewed-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: let function tipc_msg_reverse() expand header when needed

2015-07-26T23:31:50Z

The shortest TIPC message header, for cluster local CONNECTED messages, is 24 bytes long. With this format, the fields "dest_node" and "orig_node" are optimized away, since they in reality are redundant in this particular case. However, the absence of these fields leads to code inconsistencies that are difficult to handle in some cases, especially when we need to reverse or reject messages at the socket layer. In this commit, we concentrate the handling of the absent fields to one place, by letting the function tipc_msg_reverse() reallocate the buffer and expand the header to 32 bytes when necessary. This means that the socket code now can assume that the two previously absent fields are present in the header when a message needs to be rejected. This opens up for some further simplifications of the socket code. Reviewed-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: make media xmit call outside node spinlock context

2015-07-21T03:41:15Z

Currently, message sending is performed through a deep call chain, where the node spinlock is grabbed and held during a significant part of the transmission time. This is clearly detrimental to overall throughput performance; it would be better if we could send the message after the spinlock has been released. In this commit, we do instead let the call revert on the stack after the buffer chain has been added to the transmission queue, whereafter clones of the buffers are transmitted to the device layer outside the spinlock scope. As a further step in our effort to separate the roles of the node and link entities we also move the function tipc_link_xmit() to node.c, and rename it to tipc_node_xmit(). Reviewed-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: change sk_buffer handling in tipc_link_xmit()

2015-07-21T03:41:15Z

When the function tipc_link_xmit() is given a buffer list for transmission, it currently consumes the list both when transmission is successful and when it fails, except for the special case when it encounters link congestion. This behavior is inconsistent, and needs to be corrected if we want to avoid problems in later commits in this series. In this commit, we change this to let the function consume the list only when transmission is successful, and leave the list with the sender in all other cases. We also modifiy the socket code so that it adapts to this change, i.e., purges the list when a non-congestion error code is returned. Reviewed-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

net/tipc: initialize security state for new connection socket

2015-07-08T23:08:23Z

Calling connect() with an AF_TIPC socket would trigger a series of error messages from SELinux along the lines of: SELinux: Invalid class 0 type=AVC msg=audit(1434126658.487:34500): avc: denied { } for pid=292 comm="kworker/u16:5" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:unlabeled_t:s0 tclass= permissive=0 This was due to a failure to initialize the security state of the new connection sock by the tipc code, leaving it with junk in the security class field and an unlabeled secid. Add a call to security_sk_clone() to inherit the security state from the parent socket. Reported-by: Tim Shearer Signed-off-by: Stephen Smalley Acked-by: Paul Moore Acked-by: Ying Xue Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2015-06-14T06:56:52Z

tipc: disconnect socket directly after probe failure

2015-06-11T05:05:20Z

If the TIPC connection timer expires in a probing state, a self abort message is supposed to be generated and delivered to the local socket. This is currently broken, and the abort message is actually sent out to the peer node with invalid addressing information. This will cause the link to enter a constant retransmission state and eventually reset. We fix this by removing the self-abort message creation and tear down connection immediately instead. Signed-off-by: Erik Hugne Reviewed-by: Ying Xue Reviewed-by: Jon Maloy Signed-off-by: David S. Miller

tipc: unconditionally put sock refcnt when sock timer to be deleted is pending

2015-05-31T01:08:37Z

As sock refcnt is taken when sock timer is started in sk_reset_timer(), the sock refcnt should be put when sock timer to be deleted is in pending state no matter what "probing_state" value of tipc sock is. Reviewed-by: Erik Hugne Reviewed-by: Jon Maloy Signed-off-by: Ying Xue Signed-off-by: David S. Miller

tipc: simplify include dependencies

2015-05-14T16:24:45Z

When we try to add new inline functions in the code, we sometimes run into circular include dependencies. The main problem is that the file core.h, which really should be at the root of the dependency chain, instead is a leaf. I.e., core.h includes a number of header files that themselves should be allowed to include core.h. In reality this is unnecessary, because core.h does not need to know the full signature of any of the structs it refers to, only their type declaration. In this commit, we remove all dependencies from core.h towards any other tipc header file. As a consequence of this change, we can now move the function tipc_own_addr(net) from addr.c to addr.h, and make it inline. There are no functional changes in this commit. Reviewed-by: Erik Hugne Reviewed-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller