From eadc5d94950a04f9fb64cb3906644af04de81970 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>

Date: Sat, 10 Sep 2016 12:07:51 +0100

Subject: [PATCH] shared/install: fix set-default with empty root (#4118)

https://bugzilla.redhat.com/show_bug.cgi?id=1374371

When root was empty or equal to "/", chroot_symlinks_same was called with

root==NULL, and strjoina returned "", so the code thought both paths are equal

even if they were not. Fix that by always providing a non-null first argument

to strjoina.

(cherry picked from commit ae9efab711e7478b4f035edd00824d518bcf0d3c)

---

 src/shared/install.c | 3 +++

 1 file changed, 3 insertions(+)

diff --git a/src/shared/install.c b/src/shared/install.c

index cb2a2e7e0d..cf1e8349d7 100644

--- a/src/shared/install.c

+++ b/src/shared/install.c

@@ -403,6 +403,9 @@ static bool chroot_symlinks_same(const char *root, const char *wd, const char *a

         /* This will give incorrect results if the paths are relative and go outside

          * of the chroot. False negatives are possible. */

+        if (!root)

+                root = "/";

+

         a = strjoina(path_is_absolute(a) ? root : wd, "/", a);

         b = strjoina(path_is_absolute(b) ? root : wd, "/", b);

         return path_equal_or_files_same(a, b);