sockets: clear non-type bits after fd creation.

The SOCK_NONBLOCK and SOCK_CLOEXEC non-type bits are a
convenience allowed by the socket and socketpair functions, but
they prevent simple comparisons with the actual socket types
SOCK_STREAM, SOCK_DGRAM, etc.
Before this commit, opening datagram sockets with any of these
bits ORed into the type would result in TXR not realizing that
such sockets were datagram sockets because the type would be
compared directly with SOCK_DGRAM.
Various problems would ensue, such as calling listen on a
datagram socket.

This commit clears the SOCK_NONBLOCK and SOCK_CLOEXEC bits after
calling socket or socketpair so that the socket streams get the
actual socket type.
A potentially better solution would be to manually define
SOCK_TYPE_MASK as 0xF (because although Linux defines it as such
in include/linux/net.h, it doesn't export it to userspace) and
AND it with the socket type, because clearing SOCK_NONBLOCK and
SOCK_CLOEXEC will not be enough if new flags are added in the
future, and it's probably more likely for that to happen than for
SOCK_TYPE_MASK to be changed.

* socket.c (open_socket, socketpair_wrap): Clear the
SOCK_NONBLOCK and SOCK_CLOEXEC bits from the socket type after
calling socket or socketpair, and before initializing the socket
streams.

0 files changed, 0 insertions, 0 deletions