linux.git/net/tipc/socket.c, branch v4.20-rc2

Revert "net: simplify sock_poll_wait"

2018-10-23T17:57:06+00:00

This reverts commit dd979b4df817e9976f18fb6f9d134d6bc4a3c317.

This broke tcp_poll for SMC fallback: An AF_SMC socket establishes an
internal TCP socket for the initial handshake with the remote peer.
Whenever the SMC connection can not be established this TCP socket is
used as a fallback. All socket operations on the SMC socket are then
forwarded to the TCP socket. In case of poll, the file->private_data
pointer references the SMC socket because the TCP socket has no file
assigned. This causes tcp_poll to wait on the wrong socket.

Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller

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

2018-10-13T04:38:46+00:00

Conflicts were easy to resolve using immediate context mostly,
except the cls_u32.c one where I simply too the entire HEAD
chunk.

Signed-off-by: David S. Miller

tipc: queue socket protocol error messages into socket receive buffer

2018-10-11T05:56:07+00:00

In tipc_sk_filter_rcv(), when we detect protocol messages with error we
call tipc_sk_conn_proto_rcv() and let it reset the connection and notify
the socket by calling sk->sk_state_change().

However, tipc_sk_filter_rcv() may have been called from the function
tipc_backlog_rcv(), in which case the socket lock is held and the socket
already awake. This means that the sk_state_change() call is ignored and
the error notification lost. Now the receive queue will remain empty and
the socket sleeps forever.

In this commit, we convert the protocol message into a connection abort
message and enqueue it into the socket's receive queue. By this addition
to the above state change we cover all conditions.

Acked-by: Ying Xue 
Signed-off-by: Parthasarathy Bhuvaragan 
Signed-off-by: Jon Maloy 
Signed-off-by: David S. Miller

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

2018-10-04T04:00:17+00:00

Minor conflict in net/core/rtnetlink.c, David Ahern's bug fix in 'net'
overlapped the renaming of a netlink attribute in net-next.

Signed-off-by: David S. Miller

tipc: buffer overflow handling in listener socket

2018-09-29T18:24:22+00:00

Default socket receive buffer size for a listener socket is 2Mb. For
each arriving empty SYN, the linux kernel allocates a 768 bytes buffer.
This means that a listener socket can serve maximum 2700 simultaneous
empty connection setup requests before it hits a receive buffer
overflow, and much fewer if the SYN is carrying any significant
amount of data.

When this happens the setup request is rejected, and the client
receives an ECONNREFUSED error.

This commit mitigates this problem by letting the client socket try to
retransmit the SYN message multiple times when it sees it rejected with
the code TIPC_ERR_OVERLOAD. Retransmission is done at random intervals
in the range of [100 ms, setup_timeout / 4], as many times as there is
room for within the setup timeout limit.

Signed-off-by: Tung Nguyen 
Acked-by: Ying Xue 
Signed-off-by: Jon Maloy 
Signed-off-by: David S. Miller

tipc: add SYN bit to connection setup messages

2018-09-29T18:24:22+00:00

Messages intended for intitating a connection are currently
indistinguishable from regular datagram messages. The TIPC
protocol specification defines bit 17 in word 0 as a SYN bit
to allow sanity check of such messages in the listening socket,
but this has so far never been implemented.

We do that in this commit.

Acked-by: Ying Xue 
Signed-off-by: Jon Maloy 
Signed-off-by: David S. Miller

tipc: refactor function tipc_sk_filter_connect()

2018-09-29T18:24:22+00:00

We refactor the function tipc_sk_filter_connect(), both to make it
more readable and as a preparation for the next commit.

Acked-by: Ying Xue 
Signed-off-by: Jon Maloy 
Signed-off-by: David S. Miller

tipc: refactor function tipc_sk_timeout()

2018-09-29T18:24:22+00:00

We refactor this function as a preparation for the coming commits in
the same series.

Acked-by: Ying Xue 
Signed-off-by: Jon Maloy 
Signed-off-by: David S. Miller

tipc: fix flow control accounting for implicit connect

2018-09-25T17:47:37+00:00

In the case of implicit connect message with data > 1K, the flow
control accounting is incorrect. At this state, the socket does not
know the peer nodes capability and falls back to legacy flow control
by return 1, however the receiver of this message will perform the
new block accounting. This leads to a slack and eventually traffic
disturbance.

In this commit, we perform tipc_node_get_capabilities() at implicit
connect and perform accounting based on the peer's capability.

Signed-off-by: Parthasarathy Bhuvaragan 
Signed-off-by: Jon Maloy 
Signed-off-by: David S. Miller

tipc: call start and done ops directly in __tipc_nl_compat_dumpit()

2018-09-07T04:49:18+00:00

__tipc_nl_compat_dumpit() uses a netlink_callback on stack,
so the only way to align it with other ->dumpit() call path
is calling tipc_dump_start() and tipc_dump_done() directly
inside it. Otherwise ->dumpit() would always get NULL from
cb->args[].

But tipc_dump_start() uses sock_net(cb->skb->sk) to retrieve
net pointer, the cb->skb here doesn't set skb->sk, the net pointer
is saved in msg->net instead, so introduce a helper function
__tipc_dump_start() to pass in msg->net.

Ying pointed out cb->args[0...3] are already used by other
callbacks on this call path, so we can't use cb->args[0] any
more, use cb->args[4] instead.

Fixes: 9a07efa9aea2 ("tipc: switch to rhashtable iterator")
Reported-and-tested-by: syzbot+e93a2c41f91b8e2c7d9b@syzkaller.appspotmail.com
Cc: Jon Maloy 
Cc: Ying Xue 
Signed-off-by: Cong Wang 
Acked-by: Ying Xue 
Signed-off-by: David S. Miller