0083-video-readers-jpeg-Test-for-an-invalid-next-marker-r.patch 1.4 KB

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  1. From 5f5eb7ca8e971227e95745abe541df3e1509360e Mon Sep 17 00:00:00 2001
  2. From: Darren Kenny <darren.kenny@oracle.com>
  3. Date: Fri, 4 Dec 2020 15:39:00 +0000
  4. Subject: [PATCH] video/readers/jpeg: Test for an invalid next marker reference
  5. from a jpeg file
  6. While it may never happen, and potentially could be caught at the end of
  7. the function, it is worth checking up front for a bad reference to the
  8. next marker just in case of a maliciously crafted file being provided.
  9. Fixes: CID 73694
  10. Signed-off-by: Darren Kenny <darren.kenny@oracle.com>
  11. Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
  12. Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
  13. ---
  14. grub-core/video/readers/jpeg.c | 6 ++++++
  15. 1 file changed, 6 insertions(+)
  16. diff --git a/grub-core/video/readers/jpeg.c b/grub-core/video/readers/jpeg.c
  17. index 31359a4..0b6ce3c 100644
  18. --- a/grub-core/video/readers/jpeg.c
  19. +++ b/grub-core/video/readers/jpeg.c
  20. @@ -253,6 +253,12 @@ grub_jpeg_decode_quan_table (struct grub_jpeg_data *data)
  21. next_marker = data->file->offset;
  22. next_marker += grub_jpeg_get_word (data);
  23. + if (next_marker > data->file->size)
  24. + {
  25. + /* Should never be set beyond the size of the file. */
  26. + return grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: invalid next reference");
  27. + }
  28. +
  29. while (data->file->offset + sizeof (data->quan_table[id]) + 1
  30. <= next_marker)
  31. {
  32. --
  33. 2.14.2