File 0002-sss_client-Defer-thread-cancellation-until-completio.patch of Package sssd.3462

From 176a84c1add79398f342157a12945838bbb1ef0e Mon Sep 17 00:00:00 2001
From: Howard Guo <hguo@suse.de>
Date: Tue, 11 Oct 2016 10:35:13 +0200
Subject: [PATCH] sss_client: Defer thread cancellation until completion of
 nss/pam operations

https://fedorahosted.org/sssd/ticket/3156

The client code is not cancellation-safe, an application which has cancelled an NSS operation
will experience subtle bugs, hence thread cancellation is deferred until completion of client
operations.

diff -rupN sssd-1.13.4/Makefile.am sssd-1.13.4-patched/Makefile.am
--- sssd-1.13.4/Makefile.am	2016-04-13 16:48:41.000000000 +0200
+++ sssd-1.13.4-patched/Makefile.am	2016-10-11 11:20:52.812571676 +0200
@@ -696,10 +696,6 @@ endif
 
 CLIENT_LIBS = $(LTLIBINTL)
 
-if HAVE_PTHREAD
-CLIENT_LIBS += -lpthread
-endif
-
 if WITH_JOURNALD
 SYSLOG_LIBS = $(JOURNALD_LIBS)
 endif
diff -rupN sssd-1.13.4/src/sss_client/common.c sssd-1.13.4-patched/src/sss_client/common.c
--- sssd-1.13.4/src/sss_client/common.c	2016-04-13 16:48:41.000000000 +0200
+++ sssd-1.13.4-patched/src/sss_client/common.c	2016-10-11 11:20:52.812571676 +0200
@@ -1071,85 +1071,33 @@ struct sss_mutex {
     pthread_mutex_t mtx;
 
     pthread_once_t once;
-    sss_mutex_init init;
+    int old_cancel_state;
 };
 
-static void sss_nss_mt_init(void);
-static void sss_pam_mt_init(void);
 static void sss_nss_mc_mt_init(void);
 
 static struct sss_mutex sss_nss_mtx = { .mtx  = PTHREAD_MUTEX_INITIALIZER,
-                                        .once = PTHREAD_ONCE_INIT,
-                                        .init = sss_nss_mt_init };
+                                        .once = PTHREAD_ONCE_INIT };
 
 static struct sss_mutex sss_pam_mtx = { .mtx  = PTHREAD_MUTEX_INITIALIZER,
-                                        .once = PTHREAD_ONCE_INIT,
-                                        .init = sss_pam_mt_init };
+                                        .once = PTHREAD_ONCE_INIT };
 
 static struct sss_mutex sss_nss_mc_mtx = { .mtx  = PTHREAD_MUTEX_INITIALIZER,
-                                           .once = PTHREAD_ONCE_INIT,
-                                           .init = sss_nss_mc_mt_init };
-
-/* Wrappers for robust mutex support */
-static int sss_mutexattr_setrobust (pthread_mutexattr_t *attr)
-{
-#ifdef HAVE_PTHREAD_MUTEXATTR_SETROBUST
-    return pthread_mutexattr_setrobust(attr, PTHREAD_MUTEX_ROBUST);
-#elif defined(HAVE_PTHREAD_MUTEXATTR_SETROBUST_NP)
-    return pthread_mutexattr_setrobust_np(attr, PTHREAD_MUTEX_ROBUST_NP);
-#else
-#warning Robust mutexes are not supported on this platform.
-    return 0;
-#endif
-}
-
-static int sss_mutex_consistent(pthread_mutex_t *mtx)
-{
-#ifdef HAVE_PTHREAD_MUTEX_CONSISTENT
-    return pthread_mutex_consistent(mtx);
-#elif defined(HAVE_PTHREAD_MUTEX_CONSISTENT_NP)
-    return pthread_mutex_consistent_np(mtx);
-#else
-#warning Robust mutexes are not supported on this platform.
-    return 0;
-#endif
-}
-
-/* Generic mutex init, lock, unlock functions */
-static void sss_mt_init(struct sss_mutex *m)
-{
-    pthread_mutexattr_t attr;
-
-    if (pthread_mutexattr_init(&attr) != 0) {
-        return;
-    }
-    if (sss_mutexattr_setrobust(&attr) != 0) {
-        return;
-    }
-
-    pthread_mutex_init(&m->mtx, &attr);
-    pthread_mutexattr_destroy(&attr);
-}
+                                           .once = PTHREAD_ONCE_INIT };
 
 static void sss_mt_lock(struct sss_mutex *m)
 {
-    pthread_once(&m->once, m->init);
-    if (pthread_mutex_lock(&m->mtx) == EOWNERDEAD) {
-        sss_cli_close_socket();
-        sss_mutex_consistent(&m->mtx);
-    }
+    pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &m->old_cancel_state);
+    pthread_mutex_lock(&m->mtx);
 }
 
 static void sss_mt_unlock(struct sss_mutex *m)
 {
     pthread_mutex_unlock(&m->mtx);
+    pthread_setcancelstate(m->old_cancel_state, NULL);
 }
 
 /* NSS mutex wrappers */
-static void sss_nss_mt_init(void)
-{
-    sss_mt_init(&sss_nss_mtx);
-}
 void sss_nss_lock(void)
 {
     sss_mt_lock(&sss_nss_mtx);
@@ -1160,10 +1108,6 @@ void sss_nss_unlock(void)
 }
 
 /* NSS mutex wrappers */
-static void sss_pam_mt_init(void)
-{
-    sss_mt_init(&sss_pam_mtx);
-}
 void sss_pam_lock(void)
 {
     sss_mt_lock(&sss_pam_mtx);
@@ -1174,10 +1118,6 @@ void sss_pam_unlock(void)
 }
 
 /* NSS mutex wrappers */
-static void sss_nss_mc_mt_init(void)
-{
-    sss_mt_init(&sss_nss_mc_mtx);
-}
 void sss_nss_mc_lock(void)
 {
     sss_mt_lock(&sss_nss_mc_mtx);