From 0699bb82f8c260161ff11cf28024c7e25f0a5dd5 Mon Sep 17 00:00:00 2001
From: Marco A Benatto <mbenatto@redhat.com>
Date: Mon, 30 Nov 2020 12:18:24 -0300
Subject: [PATCH] loader/xnu: Free driverkey data when an error is detected in
 grub_xnu_writetree_toheap()

... to avoid memory leaks.

Fixes: CID 96640

Reference: http://git.savannah.gnu.org/cgit/grub.git/commit/?id=4b4027b6b1c877d7ab467896b04c7bd1aadcfa15

Signed-off-by: Marco A Benatto <mbenatto@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
 grub-core/loader/xnu.c | 24 ++++++++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/grub-core/loader/xnu.c b/grub-core/loader/xnu.c
index 9d40908..8efcbd2 100644
--- a/grub-core/loader/xnu.c
+++ b/grub-core/loader/xnu.c
@@ -228,26 +228,33 @@ grub_xnu_writetree_toheap (grub_addr_t *target, grub_size_t *size)
   if (! memorymap)
     return grub_errno;
 
-  driverkey = (struct grub_xnu_devtree_key *) grub_malloc (sizeof (*driverkey));
+  driverkey = (struct grub_xnu_devtree_key *) grub_zalloc (sizeof (*driverkey));
   if (! driverkey)
     return grub_errno;
   driverkey->name = grub_strdup ("DeviceTree");
   if (! driverkey->name)
-    return grub_errno;
+    {
+      err = grub_errno;
+      goto fail;
+    }
+
   driverkey->datasize = sizeof (*extdesc);
   driverkey->next = memorymap->first_child;
   memorymap->first_child = driverkey;
   driverkey->data = extdesc
     = (struct grub_xnu_extdesc *) grub_malloc (sizeof (*extdesc));
   if (! driverkey->data)
-    return grub_errno;
+    {
+      err = grub_errno;
+      goto fail;
+    }
 
   /* Allocate the space based on the size with dummy value. */
   *size = grub_xnu_writetree_get_size (grub_xnu_devtree_root, "/");
   err = grub_xnu_heap_malloc (ALIGN_UP (*size + 1, GRUB_XNU_PAGESIZE),
 			      &src, target);
   if (err)
-    return err;
+    goto fail;
 
   /* Put real data in the dummy. */
   extdesc->addr = *target;
@@ -256,6 +263,15 @@ grub_xnu_writetree_toheap (grub_addr_t *target, grub_size_t *size)
   /* Write the tree to heap. */
   grub_xnu_writetree_toheap_real (src, grub_xnu_devtree_root, "/");
   return GRUB_ERR_NONE;
+
+fail:
+  memorymap->first_child = NULL;
+
+  grub_free (driverkey->data);
+  grub_free (driverkey->name);
+  grub_free (driverkey);
+
+  return err;
 }
 
 /* Find a key or value in parent key. */
-- 
2.19.1

