[src/kqueue]: src/sys/kern filt_pipedetach(): for EVFILT_WRITE, need to detac...

[jdolecek <jdolecek%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/fda1bbb58f73
branches:  kqueue
changeset: 512502:fda1bbb58f73
user:      jdolecek <jdolecek%NetBSD.org@localhost>
date:      Sat Sep 21 19:40:35 2002 +0000

description:
filt_pipedetach(): for EVFILT_WRITE, need to detach the knote from the
  peer's pipe_sel.si_note
this fixes kernel panic for EVFILT_WRITE when the write pipe descriptor
  is closed before read or kqueue one

diffstat:

 sys/kern/sys_pipe.c |  18 ++++++++++++++++--
 1 files changed, 16 insertions(+), 2 deletions(-)

diffs (39 lines):

diff -r cd1f18258410 -r fda1bbb58f73 sys/kern/sys_pipe.c
--- a/sys/kern/sys_pipe.c       Thu Sep 19 07:18:32 2002 +0000
+++ b/sys/kern/sys_pipe.c       Sat Sep 21 19:40:35 2002 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: sys_pipe.c,v 1.5.2.8 2002/09/06 08:48:08 jdolecek Exp $        */
+/*     $NetBSD: sys_pipe.c,v 1.5.2.9 2002/09/21 19:40:35 jdolecek Exp $        */
 
 /*
  * Copyright (c) 1996 John S. Dyson
@@ -58,7 +58,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_pipe.c,v 1.5.2.8 2002/09/06 08:48:08 jdolecek Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_pipe.c,v 1.5.2.9 2002/09/21 19:40:35 jdolecek Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -1906,6 +1906,20 @@
 {
        struct pipe *cpipe = (struct pipe *)kn->kn_fp->f_data;
 
+       switch(kn->kn_filter) {
+       case EVFILT_WRITE:
+               /* need the peer structure, not our own */
+               cpipe = cpipe->pipe_peer;
+               break;
+       default:
+               /* nothing to do */
+       }
+
+#ifdef DIAGNOSTIC
+       if (kn->kn_hook != cpipe)
+               panic("filt_pipedetach: inconsistent knote");
+#endif
+
        PIPE_LOCK(cpipe);
        SLIST_REMOVE(&cpipe->pipe_sel.si_note, kn, knote, kn_selnext);
        PIPE_UNLOCK(cpipe);