Ensure that the jaildaemon dies when its fork slave is gone

1 files changed, 15 insertions, 0 deletions

diff --git a/jaildaemon.c b/jaildaemon.c
index 797f547..ae750f3 100644
--- a/jaildaemon.c
+++ b/jaildaemon.c
@@ -456,6 +456,12 @@ int main( int argc, char **argv ) {
     EV_SET( &ke, g_uds, EVFILT_VNODE, EV_ADD, NOTE_DELETE | NOTE_LINK, 0, 0);
     kevent( kq, &ke, 1, NULL, 0, NULL );
 
+    /* We want to be notified if the fork slave died. This is a good time to
+       die, too*/
+    EV_SET( &ke, g_fork_slave_fd, EVFILT_READ, EV_ADD, 0, 0, 0);
+    kevent( kq, &ke, 1, NULL, 0, NULL );
+
+
     /* If daemon was started with some initial script, fire it now
        -- this leaks some information in the command line to all jails and
        thus is disabled
@@ -554,6 +560,15 @@ int main( int argc, char **argv ) {
 
                     /* Takes a copy of our task and all string members */
                     add_task_to_kqueue( kq, &task );
+                } else if( (int)ke.ident == g_fork_slave_fd ) {
+                    /* If we see activity on the socket to the fork slave in
+                       this place, that can only mean that the slave died (EOF),
+                       or that something strange is going on over there. For now
+                       we only warn, we may switch to exerr() in the future. */
+                    if( ke.flags == EV_EOF )
+                        exerr( "Fork slave died. We die, too." );
+                    else
+                        warn( "Spurious packet from fork slave." );
                 }
                 break;
             case EVFILT_VNODE: