The value of next_marker is adjusted based on the a word sized value
read from data->file.
The updated next_marker value should reference a location in the file
just beyond the huffman table, and as such should not have a value
larger than the size of the file.
Fixes: CID 73657
Signed-off-by: Darren Kenny <darren.ke...@oracle.com>
---
grub-core/video/readers/jpeg.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/grub-core/video/readers/jpeg.c b/grub-core/video/readers/jpeg.c
index e31602f766ae..c47ffd65151e 100644
--- a/grub-core/video/readers/jpeg.c
+++ b/grub-core/video/readers/jpeg.c
@@ -199,6 +199,12 @@ grub_jpeg_decode_huff_table (struct grub_jpeg_data *data)
next_marker = data->file->offset;
next_marker += grub_jpeg_get_word (data);
+ if (next_marker > data->file->size)
+ {
+ return grub_error (GRUB_ERR_BAD_FILE_TYPE,
+ "jpeg: invalid huffman table");
+ }
+
while (data->file->offset + sizeof (count) + 1 <= next_marker)
{
id = grub_jpeg_get_byte (data);
--
2.27.0
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