[RFC,v1,0/2] vsock: handle writes to shutdowned socket

Message

Arseniy Krasnov Aug. 1, 2023, 2:17 p.m. UTC

Hello,

this small patchset adds POSIX compliant behaviour on writes to the
socket which was shutdowned with 'shutdown()' (both sides - local with
SHUT_WR flag, peer - with SHUT_RD flag). According POSIX we must send
SIGPIPE in such cases (but SIGPIPE is not send when MSG_NOSIGNAL is set).

First patch is implemented in the same way as net/ipv4/tcp.c:tcp_sendmsg_locked().
It uses 'sk_stream_error()' function which handles EPIPE error. Another
way is to use code from net/unix/af_unix.c:unix_stream_sendmsg() where
same logic from 'sk_stream_error()' is implemented "from scratch", but
it doesn't check 'sk_err' field. I think error from this field has more
priority to be returned from syscall. So I guess it is better to reuse
currently implemented 'sk_stream_error()' function.

Test is also added.

Head for this patchset is:
https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=9d0cd5d25f7d45bce01bbb3193b54ac24b3a60f3

Arseniy Krasnov (2):
  vsock: send SIGPIPE on write to shutdowned socket
  test/vsock: shutdowned socket test

 net/vmw_vsock/af_vsock.c         |   3 +
 tools/testing/vsock/vsock_test.c | 138 +++++++++++++++++++++++++++++++
 2 files changed, 141 insertions(+)