2 files changed, 55 insertions, 0 deletions
diff --git a/sysdeps/htl/pt-cond-timedwait.c b/sysdeps/htl/pt-cond-timedwait.c
index d9ce23b682..3a11e016d7 100644
--- a/sysdeps/htl/pt-cond-timedwait.c
+++ b/sysdeps/htl/pt-cond-timedwait.c
@@ -78,6 +78,10 @@ __pthread_cond_timedwait_internal (pthread_cond_t *cond,
   if (abstime && ! valid_nanoseconds (abstime->tv_nsec))
     return EINVAL;
 
+  err = __pthread_mutex_checklocked (mutex);
+  if (err)
+    return err;
+
   struct __pthread *self = _pthread_self ();
   struct cancel_ctx ctx;
   ctx.wakeup = self;
diff --git a/sysdeps/mach/hurd/htl/pt-mutex-checklocked.c b/sysdeps/mach/hurd/htl/pt-mutex-checklocked.c
new file mode 100644
index 0000000000..dea580fa04
--- /dev/null
+++ b/sysdeps/mach/hurd/htl/pt-mutex-checklocked.c
@@ -0,0 +1,51 @@
+/* __pthread_mutex_checklocked.  Hurd version.
+   Copyright (C) 2016-2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library;  if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <pthread.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <pt-internal.h>
+#include "pt-mutex.h"
+#include <hurdlock.h>
+
+int
+__pthread_mutex_checklocked (pthread_mutex_t *mtxp)
+{
+  int ret = 0;
+
+  switch (MTX_TYPE (mtxp))
+    {
+    case PT_MTX_NORMAL:
+      break;
+
+    case PT_MTX_RECURSIVE:
+    case PT_MTX_ERRORCHECK:
+    case PT_MTX_NORMAL | PTHREAD_MUTEX_ROBUST:
+    case PT_MTX_RECURSIVE | PTHREAD_MUTEX_ROBUST:
+    case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST:
+      if (!mtx_owned_p (mtxp, _pthread_self (), mtxp->__flags))
+	ret = EPERM;
+      break;
+
+    default:
+      ret = EINVAL;
+      break;
+    }
+
+  return ret;
+}