- (dtucker) [auth-pam.c] Bug #839: Ensure that pam authentication "thread"

   is terminated if the privsep slave exits during keyboard-interactive
   authentication.  ok djm@

1 files changed, 10 insertions, 3 deletions

diff --git a/auth-pam.c b/auth-pam.c
index faa0b904f..833c850e7 100644
--- a/auth-pam.c
+++ b/auth-pam.c
@@ -31,7 +31,7 @@
 
 /* Based on $FreeBSD: src/crypto/openssh/auth2-pam-freebsd.c,v 1.11 2003/03/31 13:48:18 des Exp $ */
 #include "includes.h"
-RCSID("$Id: auth-pam.c,v 1.101 2004/05/13 07:29:35 dtucker Exp $");
+RCSID("$Id: auth-pam.c,v 1.102 2004/05/24 01:55:36 dtucker Exp $");
 
 #ifdef USE_PAM
 #if defined(HAVE_SECURITY_PAM_APPL_H)
@@ -93,10 +93,17 @@ static mysig_t sshpam_oldsig;
 static void 
 sshpam_sigchld_handler(int sig)
 {
+        signal(SIGCHLD, SIG_DFL);
         if (cleanup_ctxt == NULL)
                 return; /* handler called after PAM cleanup, shouldn't happen */
-        if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0) == -1)
-                return; /* couldn't wait for process */
+        if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, WNOHANG)
+             == -1) {
+                /* PAM thread has not exitted, privsep slave must have */
+                kill(cleanup_ctxt->pam_thread, SIGTERM);
+                if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0)
+                    == -1)
+                        return; /* could not wait */
+        }
         if (WIFSIGNALED(sshpam_thread_status) &&
             WTERMSIG(sshpam_thread_status) == SIGTERM)
                 return; /* terminated by pthread_cancel */