[PATCH 6.6 04/16] fs/ntfs3: Add a check for attr_names and oatbl

Greg Kroah-Hartman
2024-07-25T14:45:15Z

From: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

commit 702d4930eb06dcfda85a2fa67e8a1a27bfa2a845 upstream.

Added out-of-bound checking for *ane (ATTR_NAME_ENTRY).

Reported-by: lei lu <llfamsec@gmail.com>
Fixes: 865e7a7700d93 ("fs/ntfs3: Reduce stack usage")
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ntfs3/fslog.c | 38 ++++++++++++++++++++++++++++++++------
1 file changed, 32 insertions(+), 6 deletions(-)

--- a/fs/ntfs3/fslog.c
+++ b/fs/ntfs3/fslog.c
@@ -3722,6 +3722,8 @@ int log_replay(struct ntfs_inode *ni, bo

u64 rec_lsn, checkpt_lsn = 0, rlsn = 0;
struct ATTR_NAME_ENTRY *attr_names = NULL;
+ u32 attr_names_bytes = 0;
+ u32 oatbl_bytes = 0;
struct RESTART_TABLE *dptbl = NULL;
struct RESTART_TABLE *trtbl = NULL;
const struct RESTART_TABLE *rt;
@@ -3736,6 +3738,7 @@ int log_replay(struct ntfs_inode *ni, bo
struct NTFS_RESTART *rst = NULL;
struct lcb *lcb = NULL;
struct OPEN_ATTR_ENRTY *oe;
+ struct ATTR_NAME_ENTRY *ane;
struct TRANSACTION_ENTRY *tr;
struct DIR_PAGE_ENTRY *dp;
u32 i, bytes_per_attr_entry;
@@ -4314,17 +4317,40 @@ check_attr_table:
lcb = NULL;

check_attribute_names2:
- if (rst->attr_names_len && oatbl) {
- struct ATTR_NAME_ENTRY *ane = attr_names;
- while (ane->off) {
+ if (attr_names && oatbl) {
+ off = 0;
+ for (;;) {
+ /* Check we can use attribute name entry 'ane'. */
+ static_assert(sizeof(*ane) == 4);
+ if (off + sizeof(*ane) > attr_names_bytes) {
+ /* just ignore the rest. */
+ break;
+ }
+
+ ane = Add2Ptr(attr_names, off);
+ t16 = le16_to_cpu(ane->off);
+ if (!t16) {
+ /* this is the only valid exit. */
+ break;
+ }
+
+ /* Check we can use open attribute entry 'oe'. */
+ if (t16 + sizeof(*oe) > oatbl_bytes) {
+ /* just ignore the rest. */
+ break;
+ }
+
/* TODO: Clear table on exit! */
- oe = Add2Ptr(oatbl, le16_to_cpu(ane->off));
+ oe = Add2Ptr(oatbl, t16);
t16 = le16_to_cpu(ane->name_bytes);
+ off += t16 + sizeof(*ane);
+ if (off > attr_names_bytes) {
+ /* just ignore the rest. */
+ break;
+ }
oe->name_len = t16 / sizeof(short);
oe->ptr = ane->name;
oe->is_attr_name = 2;
- ane = Add2Ptr(ane,
- sizeof(struct ATTR_NAME_ENTRY) + t16);
}
}