- (dtucker) [auth-pam.c] Have monitor die if PAM authentication thread exits

   unexpectedly.  with & ok djm@

2 files changed, 27 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 11329d812..95c575f41 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+20040114
+ - (dtucker) [auth-pam.c] Have monitor die if PAM authentication thread exits
+   unexpectedly.  with & ok djm@
+
 20040113
  - (dtucker) [auth-pam.c] Relocate struct pam_ctxt and prototypes.  No
    functional changes.
@@ -1659,4 +1663,4 @@
  - Fix sshd BindAddress and -b options for systems using fake-getaddrinfo.
    Report from murple@murple.net, diagnosis from dtucker@zip.com.au
 
-$Id: ChangeLog,v 1.3166 2004/01/13 11:35:58 dtucker Exp $
+$Id: ChangeLog,v 1.3167 2004/01/14 11:14:04 dtucker Exp $
diff --git a/auth-pam.c b/auth-pam.c
index fe2ae7711..14d0c7b7f 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 1.89 2004/01/13 11:35:59 dtucker Exp $");
+RCSID("$Id: auth-pam.c,v 1.90 2004/01/14 11:14:05 dtucker Exp $");
 
 #ifdef USE_PAM
 #if defined(HAVE_SECURITY_PAM_APPL_H)
@@ -86,6 +86,23 @@ static struct pam_ctxt *cleanup_ctxt;
  * Simulate threads with processes.
  */
 
+static int sshpam_thread_status = -1;
+static mysig_t sshpam_oldsig;
+
+static void 
+sshpam_sigchld_handler(int sig)
+{
+        if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0) == -1)
+                return; /* couldn't wait for process */
+        if (WIFSIGNALED(sshpam_thread_status) &&
+            WTERMSIG(sshpam_thread_status) == SIGTERM)
+                return; /* terminated by pthread_cancel */
+        if (!WIFEXITED(sshpam_thread_status))
+                fatal("PAM: authentication thread exited unexpectedly");
+        if (WEXITSTATUS(sshpam_thread_status) != 0)
+                fatal("PAM: authentication thread exited uncleanly");
+}
+
 static void
 pthread_exit(void *value __unused)
 {
@@ -107,6 +124,7 @@ pthread_create(sp_pthread_t *thread, const void *attr __unused,
                 _exit(1);
         default:
                 *thread = pid;
+                sshpam_oldsig = signal(SIGCHLD, sshpam_sigchld_handler);
                 return (0);
         }
 }
@@ -122,6 +140,9 @@ pthread_join(sp_pthread_t thread, void **value __unused)
 {
         int status;
 
+        if (sshpam_thread_status != -1)
+                return (sshpam_thread_status);
+        signal(SIGCHLD, sshpam_oldsig);
         waitpid(thread, &status, 0);
         return (status);
 }