Per listen(fd, backlog) rules, there is really no point accepting a SYN,
sending a SYNACK, and dropping the following ACK packet if accept queue
is full, because application is not draining accept queue fast enough.
This behavior is fooling TCP clients that believe they established a
flow, while there is nothing at server side. They might then send about
10 MSS (if using IW10) that will be dropped anyway while server is under
stress.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 5ea8ea2cb7f1d0db15762c9b0bb9e7330425a071)
Backport for pass Android CTS CtsLibcoreTestCases:
libcore.javax.net.ServerSocketFactoryTest#testCreateServerSocketWithPortNoBacklog
Refer the comments on libcore/luni/src/test/java/libcore/javax/net/ServerSocketFactoryTest.java
// This test may fail on kernel versions between 4.4 and 4.9, due to a kernel implementation
// detail change. Backporting the following kernel change will fix the behavior.
// http://b/31960002
// https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5ea8ea2cb7f1d0db15762c9b0bb9e7330425a071
public void testCreateServerSocketWithPortNoBacklog() throws IOException {
ServerSocket serverSocket = ServerSocketFactory.getDefault().createServerSocket(0, 1);
testSocket(serverSocket, 1);
}
Change-Id: I9bb3531480f4942447d8d4eded110aa31bc7c031
Signed-off-by: Tao Huang <huangtao@rock-chips.com>