grub2/SOURCES/0222-video-readers-png-Refu...

29 lines
1.1 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Daniel Axtens <dja@axtens.net>
Date: Tue, 6 Jul 2021 14:13:40 +1000
Subject: [PATCH] video/readers/png: Refuse to handle multiple image headers
This causes the bitmap to be leaked. Do not permit multiple image headers.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
(cherry picked from commit 8ce433557adeadbc46429aabb9f850b02ad2bdfb)
---
grub-core/video/readers/png.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/grub-core/video/readers/png.c b/grub-core/video/readers/png.c
index e2a6b1cf3c..8955b8ecfd 100644
--- a/grub-core/video/readers/png.c
+++ b/grub-core/video/readers/png.c
@@ -258,6 +258,9 @@ grub_png_decode_image_header (struct grub_png_data *data)
int color_bits;
enum grub_video_blit_format blt;
+ if (data->image_width || data->image_height)
+ return grub_error (GRUB_ERR_BAD_FILE_TYPE, "png: two image headers found");
+
data->image_width = grub_png_get_dword (data);
data->image_height = grub_png_get_dword (data);