From 100e6910fb1df6b3b7165a8b4b5107ad71538c14 Mon Sep 17 00:00:00 2001
From: dtucker <dtucker>
Date: Wed, 14 Jan 2004 11:14:04 +0000
Subject: [PATCH]  - (dtucker) [auth-pam.c] Have monitor die if PAM
 authentication thread exits    unexpectedly.  with & ok djm@

---
 ChangeLog  |  4 ++++
 auth-pam.c | 21 +++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 58ad89c3..0759caac 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.
diff --git a/auth-pam.c b/auth-pam.c
index 80e00c3b..3b363c26 100644
--- a/auth-pam.c
+++ b/auth-pam.c
@@ -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);
 }
-- 
2.45.1