0009-video-readers-png-Refuse-to-handle-multiple-image-he.patch 1.2 KB

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  1. From e170edd18fcfdd9e6f91ba750fd022cef8d43cd4 Mon Sep 17 00:00:00 2001
  2. From: Daniel Axtens <dja@axtens.net>
  3. Date: Tue, 6 Jul 2021 14:13:40 +1000
  4. Subject: [PATCH] video/readers/png: Refuse to handle multiple image headers
  5. This causes the bitmap to be leaked. Do not permit multiple image headers.
  6. Signed-off-by: Daniel Axtens <dja@axtens.net>
  7. Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
  8. Upstream: 166a4d61448f74745afe1dac2f2cfb85d04909bf
  9. [Thomas: needed to cherry-pick
  10. e623866d9286410156e8b9d2c82d6253a1b22d08, which fixes CVE-2021-3695]
  11. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
  12. ---
  13. grub-core/video/readers/png.c | 3 +++
  14. 1 file changed, 3 insertions(+)
  15. diff --git a/grub-core/video/readers/png.c b/grub-core/video/readers/png.c
  16. index d715c4629..35ae553c8 100644
  17. --- a/grub-core/video/readers/png.c
  18. +++ b/grub-core/video/readers/png.c
  19. @@ -258,6 +258,9 @@ grub_png_decode_image_header (struct grub_png_data *data)
  20. int color_bits;
  21. enum grub_video_blit_format blt;
  22. + if (data->image_width || data->image_height)
  23. + return grub_error (GRUB_ERR_BAD_FILE_TYPE, "png: two image headers found");
  24. +
  25. data->image_width = grub_png_get_dword (data);
  26. data->image_height = grub_png_get_dword (data);
  27. --
  28. 2.41.0