grub: Fix for CVE-2023-4692 and CVE-2023-4693

grub: Fix for CVE-2023-4692 and CVE-2023-4693

CVE: CVE-2023-4692

Crafted file system images can cause heap-based buffer
overflow and may allow arbitrary code execution and secure boot bypass.

Upstream-Status: Backport
[https://git.savannah.gnu.org/cgit/grub.git/commit/?id=43651027d24e62a7a463254165e1e46e42aecdea]

CVE: CVE-2023-4693

There an out-of-bounds read at fs/ntfs.c, a physically present attacker
may leverage that by presenting a specially crafted NTFS file system
image to read arbitrary memory locations. A successful attack may allow
sensitive data cached in memory or EFI variables values to be leaked
presenting a high Confidentiality risk.

Upstream-Status: Backport
[https://git.savannah.gnu.org/cgit/grub.git/commit/?id=0ed2458cc4eff6d9a9199527e2a0b6d445802f94]

Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>