grub: test for malformed jpeg files

This patch adds a fix for handling malformed JPEG files in grub's
video/readers/jpeg. It is a part of a security series [1].

[1] https://lists.gnu.org/archive/html/grub-devel/2021-03/msg00007.html

(From OE-Core rev: d8cdb3a17f6e874d232979307a3f25511172d086)

Signed-off-by: Marta Rybczynska <marta.rybczynska@huawei.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 39 insertions, 0 deletions

diff --git a/meta/recipes-bsp/grub/files/0035-video-readers-jpeg-Test-for-an-invalid-next-marker-r.patch b/meta/recipes-bsp/grub/files/0035-video-readers-jpeg-Test-for-an-invalid-next-marker-r.patch
new file mode 100644
index 0000000000..3fca2aecb5
--- /dev/null
+++ b/meta/recipes-bsp/grub/files/0035-video-readers-jpeg-Test-for-an-invalid-next-marker-r.patch
@@ -0,0 +1,38 @@
+From 88361a7fd4e481a76e1159a63c9014fa997ef29c Mon Sep 17 00:00:00 2001
+From: Darren Kenny <darren.kenny@oracle.com>
+Date: Fri, 4 Dec 2020 15:39:00 +0000
+Subject: [PATCH] video/readers/jpeg: Test for an invalid next marker reference
+ from a jpeg file
+
+While it may never happen, and potentially could be caught at the end of
+the function, it is worth checking up front for a bad reference to the
+next marker just in case of a maliciously crafted file being provided.
+
+Fixes: CID 73694
+
+Signed-off-by: Darren Kenny <darren.kenny@oracle.com>
+Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
+
+Upstream-Status: Backport [https://git.savannah.gnu.org/cgit/grub.git/commit/?id=5f5eb7ca8e971227e95745abe541df3e1509360e]
+Signed-off-by: Marta Rybczynska <marta.rybczynska@huawei.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 31359a4..0b6ce3c 100644
+--- a/grub-core/video/readers/jpeg.c
++++ b/grub-core/video/readers/jpeg.c
+@@ -253,6 +253,12 @@ grub_jpeg_decode_quan_table (struct grub_jpeg_data *data)
+   next_marker = data->file->offset;
+   next_marker += grub_jpeg_get_word (data);
+ 
++  if (next_marker > data->file->size)
++    {
++      /* Should never be set beyond the size of the file. */
++      return grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: invalid next reference");
++    }
++
+   while (data->file->offset + sizeof (data->quan_table[id]) + 1
+         <= next_marker)
+     {
diff --git a/meta/recipes-bsp/grub/grub2.inc b/meta/recipes-bsp/grub/grub2.inc
index 04c9b4c092..75782b7eb2 100644
--- a/meta/recipes-bsp/grub/grub2.inc
+++ b/meta/recipes-bsp/grub/grub2.inc
@@ -81,6 +81,7 @@ SRC_URI = "${GNU_MIRROR}/grub/grub-${PV}.tar.gz \
            file://0032-video-fb-fbfill-Fix-potential-integer-overflow.patch \
            file://0033-video-fb-video_fb-Fix-multiple-integer-overflows.patch \
            file://0034-video-fb-video_fb-Fix-possible-integer-overflow.patch \
+           file://0035-video-readers-jpeg-Test-for-an-invalid-next-marker-r.patch \
            "
 SRC_URI[md5sum] = "5ce674ca6b2612d8939b9e6abed32934"
 SRC_URI[sha256sum] = "f10c85ae3e204dbaec39ae22fa3c5e99f0665417e91c2cb49b7e5031658ba6ea"