grub2/0355-fs-ntfs-Fix-an-OOB-read-when-parsing-directory-entri.patch
Nicolas Frayer 4b81c6f969 GRUB2 NTFS driver vulnerabilities
(CVE-2023-4692)
(CVE-2023-4693)

Resolves: #2236613
Resolves: #2241978
Resolves: #2241976
Resolves: #2238343
Signed-off-by: Nicolas Frayer <nfrayer@redhat.com>
2024-03-12 14:57:26 +01:00

70 lines
2.4 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Suhanov <dfirblog@gmail.com>
Date: Tue, 3 Oct 2023 19:12:25 +0200
Subject: [PATCH] fs/ntfs: Fix an OOB read when parsing directory entries from
resident and non-resident index attributes
This fix introduces checks to ensure that index entries are never read
beyond the corresponding directory index.
The lack of this check is a minor issue, likely not exploitable in any way.
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, 11 insertions(+), 2 deletions(-)
diff --git a/grub-core/fs/ntfs.c b/grub-core/fs/ntfs.c
index 1949d48a494f..72302033281a 100644
--- a/grub-core/fs/ntfs.c
+++ b/grub-core/fs/ntfs.c
@@ -599,7 +599,7 @@ get_utf8 (grub_uint8_t *in, grub_size_t len)
}
static int
-list_file (struct grub_ntfs_file *diro, grub_uint8_t *pos,
+list_file (struct grub_ntfs_file *diro, grub_uint8_t *pos, grub_uint8_t *end_pos,
grub_fshelp_iterate_dir_hook_t hook, void *hook_data)
{
grub_uint8_t *np;
@@ -610,6 +610,9 @@ list_file (struct grub_ntfs_file *diro, grub_uint8_t *pos,
grub_uint8_t namespace;
char *ustr;
+ if ((pos >= end_pos) || (end_pos - pos < 0x52))
+ break;
+
if (pos[0xC] & 2) /* end signature */
break;
@@ -617,6 +620,9 @@ list_file (struct grub_ntfs_file *diro, grub_uint8_t *pos,
ns = *(np++);
namespace = *(np++);
+ if (2 * ns > end_pos - pos - 0x52)
+ break;
+
/*
* Ignore files in DOS namespace, as they will reappear as Win32
* names.
@@ -802,7 +808,9 @@ grub_ntfs_iterate_dir (grub_fshelp_node_t dir,
}
cur_pos += 0x10; /* Skip index root */
- ret = list_file (mft, cur_pos + u16at (cur_pos, 0), hook, hook_data);
+ ret = list_file (mft, cur_pos + u16at (cur_pos, 0),
+ at->mft->buf + (at->mft->data->mft_size << GRUB_NTFS_BLK_SHR),
+ hook, hook_data);
if (ret)
goto done;
@@ -889,6 +897,7 @@ grub_ntfs_iterate_dir (grub_fshelp_node_t dir,
(const grub_uint8_t *) "INDX")))
goto done;
ret = list_file (mft, &indx[0x18 + u16at (indx, 0x18)],
+ indx + (mft->data->idx_size << GRUB_NTFS_BLK_SHR),
hook, hook_data);
if (ret)
goto done;