integ/grub/grub2/debian/patches/0028-fs-ntfs-Fix-an-OOB-read-when-reading-data-from-the-r.patch
Li Zhou daea2d8219 grub2/grub-efi: fix CVE-2023-4692/CVE-2023-4693
Porting patches from grub2_2.06-3~deb11u6 to fix
CVE-2023-4692/CVE-2023-4693.

The source code of grub2_2.06-3~deb11u6 is from:
https://snapshot.debian.org/archive/debian-security/20231006T185629Z/
pool/updates/main/g/grub2/grub2_2.06-3~deb11u6.debian.tar.xz

Patch for CVE-2023-4692:
<fs/ntfs: Fix an OOB write when parsing the $ATTRIBUTE_LIST attribute
 for the $MFT file>
Patch for CVE-2023-4693:
<fs/ntfs: Fix an OOB read when reading data from the resident $DATA
 attribute>

No content changes for all the patches from debian release.

We do this because grub2/grub-efi is ported from wrlinux for
secure boot bringing up.

Test plan:
 - PASS: build grub2/grub-efi.
 - PASS: build-image and install and boot up on lab/qemu.
 - PASS: check that the "stx.N" version number is right for both
         bios(grub2 ver) and uefi(grub-efi ver) boot.

Closes-bug: 2038742

Signed-off-by: Li Zhou <li.zhou@windriver.com>
Change-Id: I7c8e11952fb409be93e9d777bf7da7b87414a95d
2023-10-09 22:31:36 -04:00

55 lines
2.2 KiB
Diff

From: Maxim Suhanov <dfirblog@gmail.com>
Date: Mon, 28 Aug 2023 16:32:33 +0300
Subject: fs/ntfs: Fix an OOB read when reading data from the resident $DATA
attribute
When reading a file containing resident data, i.e., the file data is stored in
the $DATA attribute within the NTFS file record, not in external clusters,
there are no checks that this resident data actually fits the corresponding
file record segment.
When parsing a specially-crafted file system image, the current NTFS code will
read the file data from an arbitrary, attacker-chosen memory offset and of
arbitrary, attacker-chosen length.
This allows an attacker to display arbitrary chunks of memory, which could
contain sensitive information like password hashes or even plain-text,
obfuscated passwords from BS EFI variables.
This fix implements a check to ensure that resident data is read from the
corresponding file record segment only.
Fixes: CVE-2023-4693
Reported-by: Maxim Suhanov <dfirblog@gmail.com>
Signed-off-by: Maxim Suhanov <dfirblog@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
grub-core/fs/ntfs.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/grub-core/fs/ntfs.c b/grub-core/fs/ntfs.c
index c3c4db1..a68e173 100644
--- a/grub-core/fs/ntfs.c
+++ b/grub-core/fs/ntfs.c
@@ -401,7 +401,18 @@ read_data (struct grub_ntfs_attr *at, grub_uint8_t *pa, grub_uint8_t *dest,
{
if (ofs + len > u32at (pa, 0x10))
return grub_error (GRUB_ERR_BAD_FS, "read out of range");
- grub_memcpy (dest, pa + u32at (pa, 0x14) + ofs, len);
+
+ if (u32at (pa, 0x10) > (at->mft->data->mft_size << GRUB_NTFS_BLK_SHR))
+ return grub_error (GRUB_ERR_BAD_FS, "resident attribute too large");
+
+ if (pa >= at->mft->buf + (at->mft->data->mft_size << GRUB_NTFS_BLK_SHR))
+ return grub_error (GRUB_ERR_BAD_FS, "resident attribute out of range");
+
+ if (u16at (pa, 0x14) + u32at (pa, 0x10) >
+ (grub_addr_t) at->mft->buf + (at->mft->data->mft_size << GRUB_NTFS_BLK_SHR) - (grub_addr_t) pa)
+ return grub_error (GRUB_ERR_BAD_FS, "resident attribute out of range");
+
+ grub_memcpy (dest, pa + u16at (pa, 0x14) + ofs, len);
return 0;
}