File 0014-video-readers-jpeg-Refuse-to-handle-multiple-start-o.patch of Package grub2.27715

From 9b6026ba4eb26eadc7ddb8df1c49f648efe257c5 Mon Sep 17 00:00:00 2001
From: Daniel Axtens <dja@axtens.net>
Date: Mon, 28 Jun 2021 14:25:17 +1000
Subject: [PATCH 14/32] video/readers/jpeg: Refuse to handle multiple start of
 streams

An invalid file could contain multiple start of stream blocks, which
would cause us to reallocate and leak our bitmap. Refuse to handle
multiple start of streams.

Additionally, fix a grub_error() call formatting.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
 grub-core/video/readers/jpeg.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/grub-core/video/readers/jpeg.c b/grub-core/video/readers/jpeg.c
index caa211f06d..1df1171d78 100644
--- a/grub-core/video/readers/jpeg.c
+++ b/grub-core/video/readers/jpeg.c
@@ -677,6 +677,9 @@ grub_jpeg_decode_sos (struct grub_jpeg_data *data)
   if (data->file->offset != data_offset)
     return grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: extra byte in sos");
 
+  if (*data->bitmap)
+    return grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: too many start of scan blocks");
+
   if (grub_video_bitmap_create (data->bitmap, data->image_width,
 				data->image_height,
 				GRUB_VIDEO_BLIT_FORMAT_RGB_888))
@@ -699,8 +702,8 @@ grub_jpeg_decode_data (struct grub_jpeg_data *data)
   nc1 = (data->image_width + hb - 1)  >> (3 + data->log_hs);
 
   if (data->bitmap_ptr == NULL)
-    return grub_error(GRUB_ERR_BAD_FILE_TYPE,
-		      "jpeg: attempted to decode data before start of stream");
+    return grub_error (GRUB_ERR_BAD_FILE_TYPE,
+		       "jpeg: attempted to decode data before start of stream");
 
   for (; data->r1 < nr1 && (!data->dri || rst);
        data->r1++, data->bitmap_ptr += (vb * data->image_width - hb * nc1) * 3)
-- 
2.34.1