diff options
Diffstat (limited to 'net/test/namespace.py')
| -rw-r--r-- | net/test/namespace.py | 27 |
1 files changed, 27 insertions, 0 deletions
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 |