Fix hang caused by a thread calling exit():

  - Block cancel signal while creating new thread to avoid losing
    the signal.

  - Terminate the process with _exit(1) if it's unsafe to continue
    calling atexit functions and destructors.

2 files changed, 75 insertions, 21 deletions

diff --git a/devel/linuxthreads/Makefile b/devel/linuxthreads/Makefile
index 2f7afeaf5b0d..7b423077e28b 100644
--- a/devel/linuxthreads/Makefile
+++ b/devel/linuxthreads/Makefile
@@ -7,7 +7,7 @@
 
 PORTNAME=	linuxthreads
 PORTVERSION=	2.2.3
-PORTREVISION=	4
+PORTREVISION=	5
 CATEGORIES=	devel
 MASTER_SITES=	${MASTER_SITE_GNU}
 MASTER_SITE_SUBDIR=	glibc
diff --git a/devel/linuxthreads/files/patch-aa b/devel/linuxthreads/files/patch-aa
index ef2383e4861d..eaa883bb2c85 100644
--- a/devel/linuxthreads/files/patch-aa
+++ b/devel/linuxthreads/files/patch-aa
@@ -466,7 +466,26 @@ diff -ru ../../work/linuxthreads-2.2.3/manager.c ./manager.c
    if (pid == 0)
      {
  #ifdef NEED_SEPARATE_REGISTER_STACK
-@@ -738,6 +750,7 @@
+@@ -628,9 +640,18 @@
+ 		     CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
+ 		     __pthread_sig_cancel, new_thread);
+ #else
++      /* Block all signals during thread creation to avoid new thread
++       * overwriting thread manager stack. 
++       */
++      sigset_t allblock_mask;
++      sigset_t oldmask;
++
++      sigfillset(&allblock_mask);
++      sigprocmask(SIG_SETMASK, &allblock_mask, &oldmask);
+       pid = __clone(pthread_start_thread, (void **) new_thread,
+ 		    CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
+ 		    __pthread_sig_cancel, new_thread);
++      sigprocmask(SIG_SETMASK, &oldmask, NULL);
+ #endif /* !NEED_SEPARATE_REGISTER_STACK */
+     }
+   /* Check if cloning succeeded */
+@@ -738,6 +759,7 @@
        /* Mark thread as exited, and if detached, free its resources */
        __pthread_lock(th->p_lock, NULL);
        th->p_exited = 1;
@@ -474,7 +493,7 @@ diff -ru ../../work/linuxthreads-2.2.3/manager.c ./manager.c
        /* If we have to signal this event do it now.  */
        if (th->p_report_events)
  	{
-@@ -757,6 +770,7 @@
+@@ -757,6 +779,7 @@
  	      __linuxthreads_reap_event();
  	    }
  	}
@@ -482,21 +501,33 @@ diff -ru ../../work/linuxthreads-2.2.3/manager.c ./manager.c
        detached = th->p_detached;
        __pthread_unlock(th->p_lock);
        if (detached)
-@@ -834,10 +848,14 @@
+@@ -834,10 +857,16 @@
  
  /* Process-wide exit() */
  
 +extern int __pthread_exit_requested_bymainthread;
++extern int __pthread_exit_alone;
 +
  static void pthread_handle_exit(pthread_descr issuing_thread, int exitcode)
  {
    pthread_descr th;
    __pthread_exit_requested = 1;
++  __pthread_exit_alone = 1;
 +  if (issuing_thread == __pthread_main_thread)
 +    __pthread_exit_requested_bymainthread = 1;
    __pthread_exit_code = exitcode;
    /* Send the CANCEL signal to all running threads, including the main
       thread, but excluding the thread from which the exit request originated
+@@ -846,6 +875,9 @@
+   for (th = issuing_thread->p_nextlive;
+        th != issuing_thread;
+        th = th->p_nextlive) {
++    /* Cancelled thread might have been in critical region unless terminated */
++    if (th->p_terminated == 0)
++      __pthread_exit_alone = 0;
+     kill(th->p_pid, __pthread_sig_cancel);
+   }
+   /* Now, wait for all these threads, so that they don't become zombies
 diff -ru ../../work/linuxthreads-2.2.3/ptfork.c ./ptfork.c
 --- ../../work/linuxthreads-2.2.3/ptfork.c	Sun Jan  7 04:35:20 2001
 +++ ./ptfork.c	Thu Jun  7 22:59:29 2001
@@ -597,15 +628,16 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
    __ATOMIC_INITIALIZER,       /* struct pthread_atomic p_resume_count */
    0,                          /* char p_woken_by_cancel */
    0,                          /* char p_condvar_avail */
-@@ -185,6 +195,7 @@
+@@ -185,6 +195,8 @@
  /* For process-wide exit() */
  
  int __pthread_exit_requested;
 +int __pthread_exit_requested_bymainthread = 0;
++int __pthread_exit_alone = 1;
  int __pthread_exit_code;
  
  /* Maximum stack size.  */
-@@ -216,11 +227,7 @@
+@@ -216,11 +228,7 @@
  
  /* Forward declarations */
  
@@ -618,7 +650,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
  static void pthread_handle_sigcancel(int sig);
  static void pthread_handle_sigrestart(int sig);
  static void pthread_handle_sigdebug(int sig);
-@@ -238,8 +245,8 @@
+@@ -238,8 +246,8 @@
  #ifndef __SIGRTMIN
  static int current_rtmin = -1;
  static int current_rtmax = -1;
@@ -629,7 +661,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
  int __pthread_sig_debug;
  #else
  static int current_rtmin;
-@@ -250,8 +257,8 @@
+@@ -250,8 +258,8 @@
  int __pthread_sig_cancel = __SIGRTMIN + 1;
  int __pthread_sig_debug = __SIGRTMIN + 2;
  #else
@@ -640,7 +672,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
  int __pthread_sig_debug;
  #endif
  
-@@ -348,26 +355,17 @@
+@@ -348,26 +356,17 @@
  static int
  is_smp_system (void)
  {
@@ -676,7 +708,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
  }
  
  
-@@ -448,13 +446,7 @@
+@@ -448,13 +447,7 @@
    /* Register an exit function to kill all other threads. */
    /* Do it early so that user-registered atexit functions are called
       before pthread_*exit_process. */
@@ -691,7 +723,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
    /* How many processors.  */
    __pthread_smp_kernel = is_smp_system ();
  }
-@@ -502,12 +494,6 @@
+@@ -502,12 +495,6 @@
    int pid;
    struct pthread_request request;
  
@@ -704,7 +736,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
    if (__pthread_max_stacksize == 0)
      __pthread_init_max_stacksize ();
    /* If basic initialization not done yet (e.g. we're called from a
-@@ -525,6 +511,7 @@
+@@ -525,6 +512,7 @@
    }
    /* Start the thread manager */
    pid = 0;
@@ -712,7 +744,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
    if (__builtin_expect (__pthread_initial_thread.p_report_events, 0))
      {
        /* It's a bit more complicated.  We have to report the creation of
-@@ -572,17 +559,20 @@
+@@ -572,17 +560,20 @@
  	  __pthread_unlock(__pthread_manager_thread.p_lock);
  	}
      }
@@ -735,7 +767,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
  		    (void *)(long)manager_pipe[0]);
  #endif
      }
-@@ -715,7 +705,7 @@
+@@ -715,7 +706,7 @@
      __pthread_unlock(&handle->h_lock);
      return errno;
    }
@@ -744,7 +776,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
    __pthread_unlock(&handle->h_lock);
    if (__pthread_manager_request >= 0)
      __pthread_manager_adjust_prio(th->p_priority);
-@@ -751,7 +741,7 @@
+@@ -751,7 +742,7 @@
  
  /* Process-wide exit() request */
  
@@ -753,7 +785,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
  {
    if (__builtin_expect (__pthread_manager_request, 0) >= 0) {
      struct pthread_request request;
-@@ -759,7 +749,7 @@
+@@ -759,7 +750,7 @@
  
      request.req_thread = self;
      request.req_kind = REQ_PROCESS_EXIT;
@@ -762,7 +794,29 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
      __libc_write(__pthread_manager_request,
  		 (char *) &request, sizeof(request));
      suspend(self);
-@@ -774,19 +764,6 @@
+@@ -768,25 +759,28 @@
+     if (self == __pthread_main_thread)
+       {
+ 	waitpid(__pthread_manager_thread.p_pid, NULL, __WCLONE);
++	/*
++	 * If other threads have been canceled then proper cleanup
++	 * cannot be performed since a canceled thread might have
++	 * been inside a critical region of code with a spinlock
++	 * held, a system mutex held, or a mutex partially held.
++	 */
++	if (__pthread_exit_alone == 0)
++	  _exit(1);
+ 	free (__pthread_manager_thread_bos);
+ 	__pthread_manager_thread_bos = __pthread_manager_thread_tos = NULL;
+       }
++    /*
++     * If other threads have been canceled then proper cleanup
++     * cannot be performed since a canceled thread might have
++     * been inside a critical region of code with a spinlock
++     * held, a system mutex held, or a mutex partially held.
++     */
++    if (__pthread_exit_alone == 0)
++      _exit(1);
    }
  }
  
@@ -782,7 +836,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
  
  /* The handler for the RESTART signal just records the signal received
     in the thread descriptor, and optionally performs a siglongjmp
-@@ -818,6 +795,9 @@
+@@ -818,6 +812,9 @@
    if (__builtin_expect (__pthread_exit_requested, 0)) {
      /* Main thread should accumulate times for thread manager and its
         children, so that timings for main thread account for all threads. */
@@ -792,7 +846,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
      if (self == __pthread_main_thread)
        waitpid(__pthread_manager_thread.p_pid, NULL, __WCLONE);
      _exit(__pthread_exit_code);
-@@ -894,7 +874,7 @@
+@@ -894,7 +891,7 @@
  {
    struct sigaction sa;
    /* Terminate all other threads and thread manager */
@@ -801,7 +855,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
    /* Make current thread the main thread in case the calling thread
       changes its mind, does not exec(), and creates new threads instead. */
    __pthread_reset_main_thread();
-@@ -967,7 +947,7 @@
+@@ -967,7 +964,7 @@
  __pthread_timedsuspend_old(pthread_descr self, const struct timespec *abstime)
  {
    sigset_t unblock, initial_mask;
@@ -810,7 +864,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
    sigjmp_buf jmpbuf;
  
    if (atomic_decrement(&self->p_resume_count) == 0) {
-@@ -1131,3 +1111,17 @@
+@@ -1131,3 +1128,17 @@
  static const int *const __pthread_require_wrappers =
    &__pthread_provide_wrappers;
  #endif