diff -r 104fdc42bcd1 Modules/posixmodule.c
--- a/Modules/posixmodule.c	Tue Dec 06 13:43:46 2016 +0200
+++ b/Modules/posixmodule.c	Tue Dec 06 17:14:48 2016 -0800
@@ -2795,6 +2795,8 @@
 
 #ifdef MS_WINDOWS
     DWORD attr;
+#else
+    int async_err = 0;
 #endif
 
 #ifdef HAVE_FCHMODAT
@@ -2830,44 +2832,47 @@
         return path_error(path);
     }
 #else /* MS_WINDOWS */
-    Py_BEGIN_ALLOW_THREADS
+    do {
+        Py_BEGIN_ALLOW_THREADS
 #ifdef HAVE_FCHMOD
-    if (path->fd != -1)
-        result = fchmod(path->fd, mode);
-    else
+        if (path->fd != -1)
+            result = fchmod(path->fd, mode);
+        else
 #endif
 #ifdef HAVE_LCHMOD
-    if ((!follow_symlinks) && (dir_fd == DEFAULT_DIR_FD))
-        result = lchmod(path->narrow, mode);
-    else
+        if ((!follow_symlinks) && (dir_fd == DEFAULT_DIR_FD))
+            result = lchmod(path->narrow, mode);
+        else
 #endif
 #ifdef HAVE_FCHMODAT
-    if ((dir_fd != DEFAULT_DIR_FD) || !follow_symlinks) {
-        /*
-         * fchmodat() doesn't currently support AT_SYMLINK_NOFOLLOW!
-         * The documentation specifically shows how to use it,
-         * and then says it isn't implemented yet.
-         * (true on linux with glibc 2.15, and openindiana 3.x)
-         *
-         * Once it is supported, os.chmod will automatically
-         * support dir_fd and follow_symlinks=False.  (Hopefully.)
-         * Until then, we need to be careful what exception we raise.
-         */
-        result = fchmodat(dir_fd, path->narrow, mode,
-                          follow_symlinks ? 0 : AT_SYMLINK_NOFOLLOW);
-        /*
-         * But wait!  We can't throw the exception without allowing threads,
-         * and we can't do that in this nested scope.  (Macro trickery, sigh.)
-         */
-        fchmodat_nofollow_unsupported =
-                         result &&
-                         ((errno == ENOTSUP) || (errno == EOPNOTSUPP)) &&
-                         !follow_symlinks;
-    }
-    else
-#endif
-        result = chmod(path->narrow, mode);
-    Py_END_ALLOW_THREADS
+        if ((dir_fd != DEFAULT_DIR_FD) || !follow_symlinks) {
+            /*
+             * fchmodat() doesn't currently support AT_SYMLINK_NOFOLLOW!
+             * The documentation specifically shows how to use it,
+             * and then says it isn't implemented yet.
+             * (true on linux with glibc 2.15, and openindiana 3.x)
+             *
+             * Once it is supported, os.chmod will automatically
+             * support dir_fd and follow_symlinks=False.  (Hopefully.)
+             * Until then, we need to be careful what exception we raise.
+             */
+            result = fchmodat(dir_fd, path->narrow, mode,
+                              follow_symlinks ? 0 : AT_SYMLINK_NOFOLLOW);
+            /*
+             * But wait!  We can't throw the exception without allowing threads,
+             * and we can't do that in this nested scope. (Macro tricks, sigh.)
+             */
+            fchmodat_nofollow_unsupported =
+                             result &&
+                             ((errno == ENOTSUP) || (errno == EOPNOTSUPP)) &&
+                             !follow_symlinks;
+        }
+        else
+#endif
+            result = chmod(path->narrow, mode);
+        Py_END_ALLOW_THREADS
+    } while (result != 0 && errno == EINTR &&
+             !(async_err = PyErr_CheckSignals()));
 
     if (result) {
 #ifdef HAVE_FCHMODAT
@@ -2880,7 +2885,11 @@
         }
         else
 #endif
-        return path_error(path);
+        if (async_err) {
+            return NULL;
+        } else {
+            return path_error(path);
+        }
     }
 #endif