3 files changed, 24 insertions, 1 deletions
diff --git a/lib/libthr/thread/thr_create.c b/lib/libthr/thread/thr_create.c
index 03f0584..3bfd3b3 100644
--- a/lib/libthr/thread/thr_create.c
+++ b/lib/libthr/thread/thr_create.c
@@ -123,6 +123,11 @@ _pthread_create(pthread_t * thread, const pthread_attr_t * attr,
 	if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED)
 		new_thread->tlflags |= TLFLAGS_DETACHED;
 
+	if (curthread->in_sigcancel_handler)
+		new_thread->unblock_sigcancel = 1;
+	else
+		new_thread->unblock_sigcancel = 0;
+
 	/* Add the new thread. */
 	new_thread->refcount = 1;
 	_thr_link(curthread, new_thread);
@@ -172,8 +177,10 @@ _pthread_create(pthread_t * thread, const pthread_attr_t * attr,
 			ret = EAGAIN;
 	}
 
-	if (create_suspended)
+	if (create_suspended) {
 		__sys_sigprocmask(SIG_SETMASK, &oset, NULL);
+		SIGDELSET(oset, SIGCANCEL);
+	}
 
 	if (ret != 0) {
 		if (!locked)
@@ -217,6 +224,14 @@ create_stack(struct pthread_attr *pattr)
 static void
 thread_start(struct pthread *curthread)
 {
+	if (curthread->unblock_sigcancel) {
+		sigset_t set;
+
+		SIGEMPTYSET(set);
+		SIGADDSET(set, SIGCANCEL);
+		sigprocmask(SIG_UNBLOCK, &set, NULL);
+	}
+
 	if (curthread->attr.suspend == THR_CREATE_SUSPENDED) {
 		sigset_t set = curthread->sigmask;
 
diff --git a/lib/libthr/thread/thr_private.h b/lib/libthr/thread/thr_private.h
index 4db3b7a..ff9f52b 100644
--- a/lib/libthr/thread/thr_private.h
+++ b/lib/libthr/thread/thr_private.h
@@ -378,6 +378,12 @@ struct pthread {
 	/* Thread temporary signal mask. */
 	sigset_t		sigmask;
 
+	/* Thread is in SIGCANCEL handler. */
+	int			in_sigcancel_handler;
+
+	/* New thread should unblock SIGCANCEL. */
+	int			unblock_sigcancel;
+
 	/* Thread state: */
 	enum pthread_state 	state;
 
diff --git a/lib/libthr/thread/thr_sig.c b/lib/libthr/thread/thr_sig.c
index 6da4b90..c8ebc24 100644
--- a/lib/libthr/thread/thr_sig.c
+++ b/lib/libthr/thread/thr_sig.c
@@ -69,7 +69,9 @@ sigcancel_handler(int sig __unused,
 
 	if (curthread->cancel_defer && curthread->cancel_pending)
 		thr_wake(curthread->tid);
+	curthread->in_sigcancel_handler = 1;
 	_thr_ast(curthread);
+	curthread->in_sigcancel_handler = 0;
 }
 
 void