On Sat, 5 Sep 2020 15:14:47 +0900 Tetsuo Handa wrote:
> I confirmed that the problem fixed by commit 2a63866c8b51a3f7 ("tipc: fix
> shutdown() of connectionless socket") also applies to stream socket.
>
> ----------
> #include <sys/socket.h>
> #include <unistd.h>
> #include <sys/wait.h>
>
> int main(int argc, char *argv[])
> {
> int fds[2] = { -1, -1 };
> socketpair(PF_TIPC, SOCK_STREAM /* or SOCK_DGRAM */, 0, fds);
> if (fork() == 0)
> _exit(read(fds[0], NULL, 1));
> shutdown(fds[0], SHUT_RDWR); /* This must make read() return. */
> wait(NULL); /* To be woken up by _exit(). */
> return 0;
> }
> ----------
>
> Since shutdown(SHUT_RDWR) should affect all processes sharing that socket,
> unconditionally setting sk->sk_shutdown to SHUTDOWN_MASK will be the right
> behavior.
>
> Signed-off-by: Tetsuo Handa <[email protected]>
Jon, this looks correct to me but it may change the behavior for
applications (at least poll events).
Please review.
> diff --git a/net/tipc/socket.c b/net/tipc/socket.c
> index ebd280e767bd..11b27ddc75ba 100644
> --- a/net/tipc/socket.c
> +++ b/net/tipc/socket.c
> @@ -2771,10 +2771,7 @@ static int tipc_shutdown(struct socket *sock, int how)
>
> trace_tipc_sk_shutdown(sk, NULL, TIPC_DUMP_ALL, " ");
> __tipc_shutdown(sock, TIPC_CONN_SHUTDOWN);
> - if (tipc_sk_type_connectionless(sk))
> - sk->sk_shutdown = SHUTDOWN_MASK;
> - else
> - sk->sk_shutdown = SEND_SHUTDOWN;
> + sk->sk_shutdown = SHUTDOWN_MASK;
>
> if (sk->sk_state == TIPC_DISCONNECTING) {
> /* Discard any unreceived messages */