diff options
| -rw-r--r-- | source3/lib/events.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/source3/lib/events.c b/source3/lib/events.c index 9ff14880ec..499d92edd2 100644 --- a/source3/lib/events.c +++ b/source3/lib/events.c @@ -260,6 +260,29 @@ bool run_events_poll(struct tevent_context *ev, int pollrtn, if (pfd->revents & (POLLIN|POLLHUP|POLLERR)) { flags |= EVENT_FD_READ; + + if ((fde->flags & EVENT_FD_READ) == 0) { + /* + * This one is a bit subtle. If a socket is + * not being asked for readability and dies + * with POLLHUP|POLLERR, then the write + * handler must be activated to detect the + * dead socket with a failed write(2) + * call. The error I've seen is winbind + * spinning in poll trying to send something + * to a DC on a dead socket. poll gave + * POLLHUP|POLLERR, but because winbind at + * this moment only had asked for socket + * writability, it spun. + * + * We can't activate EVENT_FD_WRITE though + * whenever we have an error condition via + * POLLHUP|POLLERR, because at least smbd + * monitors EVENT_FD_WRITE in its callback, + * doing nothing. + */ + flags |= EVENT_FD_WRITE; + } } if (pfd->revents & POLLOUT) { flags |= EVENT_FD_WRITE; |