From 913b27b3578839e04d3199f7eb24500ae07c20da Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Maciej=20=C5=BBenczykowski?= Date: Wed, 1 Jun 2022 22:48:44 +0000 Subject: net-test: fix mixed build R+T lack of tcp_default_init_rwnd on old 4.14 kernels MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Tested at 4.14.181 (android-4.14-stable) at commit 08870bd1a24fc7f3ae4ff30bc7e64c09edd931d4 ANDROID: namespace'ify tcp_default_init_rwnd implementation and the commit immediately prior to it. in UML with namespaces always enabled via: ARCH=um SUBARCH=x86_64 /aosp-tests/net/test/run_net_test.sh --builder all_tests.py at both commit 08870bd1a24fc7f3ae4ff30bc7e64c09edd931d4 and the preceding one (4f02b6c9ac416630a215a911e9b431cfd5f3cd98) Bug: 216652717 Test: TreeHugger Signed-off-by: Maciej Żenczykowski Change-Id: I5d06a2e3c3c323dfa45d4ad6a82a93f164d6ce74 (cherry picked from commit 975366a206bec8e48a5ae8bbe7fc2820315b2e7f) Merged-In: I5d06a2e3c3c323dfa45d4ad6a82a93f164d6ce74 --- net/test/namespace.py | 27 +++++++++++++++++++++++++++ net/test/sock_diag_test.py | 18 +++++++++++++++++- 2 files changed, 44 insertions(+), 1 deletion(-) diff --git a/net/test/namespace.py b/net/test/namespace.py index c8f8f46..3c0a0c1 100644 --- a/net/test/namespace.py +++ b/net/test/namespace.py @@ -18,6 +18,7 @@ import ctypes import ctypes.util +import errno import os import socket import sys @@ -128,6 +129,12 @@ def IfPossibleEnterNewNetworkNamespace(): sys.stdout.write('Creating clean namespace... ') + # sysctl only present on 4.14 and earlier Android kernels + if net_test.LINUX_VERSION < (4, 15, 0): + TCP_DEFAULT_INIT_RWND = "/proc/sys/net/ipv4/tcp_default_init_rwnd" + # In root netns this will succeed + init_rwnd_sysctl = open(TCP_DEFAULT_INIT_RWND, "w") + try: UnShare(CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWNET) except OSError as err: @@ -148,6 +155,26 @@ def IfPossibleEnterNewNetworkNamespace(): # We've already transitioned into the new netns -- it's too late to recover. raise + if net_test.LINUX_VERSION < (4, 15, 0): + # In non-root netns this open might fail due to non-namespace-ified sysctl + # ie. lack of kernel commit: + # https://android-review.googlesource.com/c/kernel/common/+/1312623 + # ANDROID: namespace'ify tcp_default_init_rwnd implementation + try: + init_rwnd_sysctl = open(TCP_DEFAULT_INIT_RWND, "w") + except IOError as e: + if e.errno != errno.ENOENT: + raise + # Note! if the netns open above succeeded (and thus we don't reach here) + # then we don't need to actually update the sysctl, since we'll be able to do + # that in the sock_diag_test.py TcpRcvWindowTest test case setUp() call instead. + # + # As such this write here is *still* to the root netns sysctl + # (because we obtained a file descriptor *prior* to unshare/etc...) + # and handles the case where the sysctl is not namespace aware and thus + # affects the entire system. + init_rwnd_sysctl.write("60"); + print('succeeded.') return True diff --git a/net/test/sock_diag_test.py b/net/test/sock_diag_test.py index 39ace4c..beda5e4 100755 --- a/net/test/sock_diag_test.py +++ b/net/test/sock_diag_test.py @@ -562,7 +562,23 @@ class TcpRcvWindowTest(tcp_test.TcpBaseTest, SockDiagBaseTest): self.assertRaisesErrno(ENOENT, open, self.TCP_DEFAULT_INIT_RWND, "w") return - f = open(self.TCP_DEFAULT_INIT_RWND, "w") + try: + f = open(self.TCP_DEFAULT_INIT_RWND, "w") + except IOError as e: + # sysctl was namespace-ified on May 25, 2020 in android-4.14-stable [R] + # just after 4.14.181 by: + # https://android-review.googlesource.com/c/kernel/common/+/1312623 + # ANDROID: namespace'ify tcp_default_init_rwnd implementation + # But that commit might be missing in Q era kernels even when > 4.14.181 + # when running T vts. + if net_test.LINUX_VERSION >= (4, 15, 0): + raise + if e.errno != ENOENT: + raise + # we rely on the network namespace creation code + # modifying the root netns sysctl before the namespace is even created + return + f.write("60") def checkInitRwndSize(self, version, netid): -- cgit v1.2.3