EDOOFUS

Prevent one thread from messing up another thread's saved signal
mask by saving it in struct pthread instead of leaving it as a
global variable. D'oh!

Approved by:	re/blanket libthr

lib/libthr/thread/thr_kern.c

@@ -73,8 +73,7 @@ _thread_critical_enter(pthread_t pthread)
 		    errno);
 		abort();
 	}
-
-	restore = sav;
+	curthread->savedsig = sav;
 }
 
 void
@@ -82,17 +81,10 @@ _thread_critical_exit(pthread_t pthread)
 {
 	sigset_t set;
 
-	/*
-	 * restore is protected by giant.  We could restore our signal state
-	 * incorrectly if someone else set restore between unlocking giant
-	 * and restoring the signal mask.  To avoid this we cache a copy prior
-	 * to the unlock.
-	 */
-	set = restore;
-
 	/*
 	 * Restore signals.
 	 */
+	set = curthread->savedsig;
 	if (__sys_sigprocmask(SIG_SETMASK, &set, NULL)) {
 		_thread_printf(STDERR_FILENO, "Critical Exit: sig err %d\n",
 		    errno);

lib/libthr/thread/thr_private.h

@@ -425,6 +425,7 @@ struct pthread {
 	char			*name;
 	u_int64_t		uniqueid; /* for gdb */
 	thr_id_t		thr_id;
+	sigset_t		savedsig;
 
 	/*
 	 * Lock for accesses to this thread structure.