From 28146206578ebe1b84b48e6f255738a227058c04 Mon Sep 17 00:00:00 2001 From: Artem Khramov Date: Thu, 15 Aug 2019 03:21:48 +0600 Subject: bpo-37811: FreeBSD, OSX: fix poll(2) usage in sockets module (GH-15202) FreeBSD implementation of poll(2) restricts the timeout argument to be either zero, or positive, or equal to INFTIM (-1). Unless otherwise overridden, socket timeout defaults to -1. This value is then converted to milliseconds (-1000) and used as argument to the poll syscall. poll returns EINVAL (22), and the connection fails. This bug was discovered during the EINTR handling testing, and the reproduction code can be found in https://bugs.python.org/issue23618 (see connect_eintr.py, attached). On GNU/Linux, the example runs as expected. This change is trivial: If the supplied timeout value is negative, truncate it to -1. --- Modules/socketmodule.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'Modules/socketmodule.c') diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c index f220c26363..d4f2098e1e 100755 --- a/Modules/socketmodule.c +++ b/Modules/socketmodule.c @@ -789,6 +789,17 @@ internal_select(PySocketSockObject *s, int writing, _PyTime_t interval, ms = _PyTime_AsMilliseconds(interval, _PyTime_ROUND_CEILING); assert(ms <= INT_MAX); + /* On some OSes, typically BSD-based ones, the timeout parameter of the + poll() syscall, when negative, must be exactly INFTIM, where defined, + or -1. See issue 37811. */ + if (ms < 0) { +#ifdef INFTIM + ms = INFTIM; +#else + ms = -1; +#endif + } + Py_BEGIN_ALLOW_THREADS; n = poll(&pollfd, 1, (int)ms); Py_END_ALLOW_THREADS; -- cgit v1.2.1