boot/grub2/0009-gfxmenu-Fix-double-free-in-load_image.patch

From 9ff609f0e7798bc5fb04f791131c98e7693bdd9b Mon Sep 17 00:00:00 2001
From: Alexey Makhalov <amakhalov@vmware.com>
Date: Wed, 8 Jul 2020 20:41:56 +0000
Subject: [PATCH] gfxmenu: Fix double free in load_image()
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self->bitmap should be zeroed after free. Otherwise, there is a chance
to double free (USE_AFTER_FREE) it later in rescale_image().

Fixes: CID 292472

Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
---
 grub-core/gfxmenu/gui_image.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/grub-core/gfxmenu/gui_image.c b/grub-core/gfxmenu/gui_image.c
index 29784ed2d..6b2e976f1 100644
--- a/grub-core/gfxmenu/gui_image.c
+++ b/grub-core/gfxmenu/gui_image.c
@@ -195,7 +195,10 @@ load_image (grub_gui_image_t self, const char *path)
     return grub_errno;
 
   if (self->bitmap && (self->bitmap != self->raw_bitmap))
-    grub_video_bitmap_destroy (self->bitmap);
+    {
+      grub_video_bitmap_destroy (self->bitmap);
+      self->bitmap = 0;
+    }
   if (self->raw_bitmap)
     grub_video_bitmap_destroy (self->raw_bitmap);
 
-- 
2.26.2