- dtucker@cvs.openbsd.org 2007/02/21 11:00:05

     [sshd.c]
     Clear alarm() before restarting sshd on SIGHUP.  Without this, if there's
     a SIGALRM pending (for SSH1 key regeneration) when sshd is SIGHUP'ed, the
     newly exec'ed sshd will get the SIGALRM and not have a handler for it,
     and the default action will terminate the listening sshd.  Analysis and
     patch from andrew at gaul.org.

2 files changed, 10 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 33919d4e7..693cb9616 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,13 @@
      [clientloop.c]
      set maximum packet and window sizes the same for multiplexed clients
      as normal connections; ok markus@
+   - dtucker@cvs.openbsd.org 2007/02/21 11:00:05
+     [sshd.c]
+     Clear alarm() before restarting sshd on SIGHUP.  Without this, if there's
+     a SIGALRM pending (for SSH1 key regeneration) when sshd is SIGHUP'ed, the
+     newly exec'ed sshd will get the SIGALRM and not have a handler for it,
+     and the default action will terminate the listening sshd.  Analysis and
+     patch from andrew at gaul.org.
 
 20070219
   - (dtucker) OpenBSD CVS Sync
@@ -2749,4 +2756,4 @@
    OpenServer 6 and add osr5bigcrypt support so when someone migrates
    passwords between UnixWare and OpenServer they will still work. OK dtucker@
 
-$Id: ChangeLog,v 1.4620 2007/02/25 09:36:49 dtucker Exp $
+$Id: ChangeLog,v 1.4621 2007/02/25 09:37:21 dtucker Exp $
diff --git a/sshd.c b/sshd.c
index 4aa1c98ed..0a76f2d3a 100644
--- a/sshd.c
+++ b/sshd.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshd.c,v 1.348 2006/11/06 21:25:28 markus Exp $ */
+/* $OpenBSD: sshd.c,v 1.349 2007/02/21 11:00:05 dtucker Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -305,6 +305,7 @@ sighup_restart(void)
         logit("Received SIGHUP; restarting.");
         close_listen_socks();
         close_startup_pipes();
+        alarm(0);  /* alarm timer persists across exec */
         execv(saved_argv[0], saved_argv);
         logit("RESTART FAILED: av[0]='%.100s', error: %.100s.", saved_argv[0],
             strerror(errno));