From b6ffe7ec63d86c5ac66171d6731068b87e3e7b50 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Sat, 27 Jun 2020 11:13:01 +0200
Subject: [PATCH] mount-util: use UMOUNT_NOFOLLOW in recursive umounter

When we only want to unmount mount points below some path then it is
against our interest to follow symlinks. Hence don't.

(cherry picked from commit 827ea5212507c3833b6ae14cdf65e446b36b5e05)

Related: #1885143
---
 src/basic/mount-util.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/basic/mount-util.c b/src/basic/mount-util.c
index 2cf98eaa84..be26bb5ec1 100644
--- a/src/basic/mount-util.c
+++ b/src/basic/mount-util.c
@@ -346,8 +346,8 @@ int umount_recursive(const char *prefix, int flags) {
                         if (!path_startswith(path, prefix))
                                 continue;
 
-                        if (umount2(path, flags) < 0) {
-                                r = log_debug_errno(errno, "Failed to umount %s: %m", path);
+                        if (umount2(path, flags | UMOUNT_NOFOLLOW) < 0) {
+                                log_debug_errno(errno, "Failed to umount %s: %m", path);
                                 continue;
                         }