grub2/0279-editenv-handle-relative-symlinks.patch

From ac9408d85d219cd0d871b0507c32cdc653d55f28 Mon Sep 17 00:00:00 2001
From: Jonathan Lebon <jlebon@redhat.com>
Date: Mon, 14 Aug 2017 14:37:20 -0400
Subject: [PATCH] editenv: handle relative symlinks

Handle symlinks with targets relative to the containing dir. This
ensures that the rename operation does not depend on the cwd.

Resolves: rhbz#1479960

Signed-off-by: Jonathan Lebon <jlebon@redhat.com>
---
 util/editenv.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/util/editenv.c b/util/editenv.c
index d8d1dad6ab9..41bc7cb1c9a 100644
--- a/util/editenv.c
+++ b/util/editenv.c
@@ -28,6 +28,7 @@
 
 #include <errno.h>
 #include <string.h>
+#include <libgen.h>
 
 #define DEFAULT_ENVBLK_SIZE	1024
 
@@ -87,9 +88,20 @@ grub_util_create_envblk_file (const char *name)
 	  continue;
 	}
 
-      free (rename_target);
       linkbuf[retsize] = '\0';
-      rename_target = linkbuf;
+      if (linkbuf[0] == '/')
+        {
+          free (rename_target);
+          rename_target = linkbuf;
+        }
+      else
+        {
+          char *dbuf = xstrdup (rename_target);
+          const char *dir = dirname (dbuf);
+          free (rename_target);
+          rename_target = xasprintf("%s/%s", dir, linkbuf);
+          free (dbuf);
+        }
     }
 
   int rc = grub_util_rename (namenew, rename_target);