use same close logic for stderr as stdout

Avoids sending SIGPIPE to child processes after their parent exits
if they attempt to write to stderr.

Analysis and patch from JD Paul; patch reworked by Jakub Jelen and
myself. bz#2071; ok dtucker@

diff --git a/channels.c b/channels.c
index 19da16eb3706117ae006eb3093bd794e9c63d846..657381b8037d67aab96aab83521d11567fd898c7 100644 (file)
--- a/channels.c
+++ b/channels.c
@@ -2100,16 +2100,18 @@ channel_handle_efd_read(struct ssh *ssh, Channel *c,
     fd_set *readset, fd_set *writeset)
 {
        char buf[CHAN_RBUF];
-       int r;
        ssize_t len;
+       int r, force;
+
+       force = c->isatty && c->detach_close && c->istate != CHAN_INPUT_CLOSED;
 
-       if (!c->detach_close && !FD_ISSET(c->efd, readset))
+       if (c->efd == -1 || (!force && !FD_ISSET(c->efd, readset)))
                return 1;
 
        len = read(c->efd, buf, sizeof(buf));
        debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
        if (len < 0 && (errno == EINTR || ((errno == EAGAIN ||
-           errno == EWOULDBLOCK) && !c->detach_close)))
+           errno == EWOULDBLOCK) && !force)))
                return 1;
        if (len <= 0) {
                debug2("channel %d: closing read-efd %d",