fs/ntfs3: Add more checks in mi_enum_attr (part 2)

Add offset check before access to attr->non_res field as mentioned in [1].

[1] https://lore.kernel.org/ntfs3/20241010110005.42792-1-llfamsec@gmail.com/

Suggested-by: lei lu <llfamsec@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

diff --git a/fs/ntfs3/record.c b/fs/ntfs3/record.c
index f810f04..61d53d3 100644 (file)
--- a/fs/ntfs3/record.c
+++ b/fs/ntfs3/record.c
@@ -212,7 +212,7 @@ struct ATTRIB *mi_enum_attr(struct mft_inode *mi, struct ATTRIB *attr)
                        return NULL;
 
                if (off >= used || off < MFTRECORD_FIXUP_OFFSET_1 ||
-                   !IS_ALIGNED(off, 4)) {
+                   !IS_ALIGNED(off, 8)) {
                        return NULL;
                }
 
@@ -236,8 +236,11 @@ struct ATTRIB *mi_enum_attr(struct mft_inode *mi, struct ATTRIB *attr)
                off += asize;
        }
 
-       /* Can we use the first field (attr->type). */
-       /* NOTE: this code also checks attr->size availability. */
+       /*
+        * Can we use the first fields:
+        * attr->type,
+        * attr->size
+        */
        if (off + 8 > used) {
                static_assert(ALIGN(sizeof(enum ATTR_TYPE), 8) == 8);
                return NULL;
@@ -259,10 +262,17 @@ struct ATTRIB *mi_enum_attr(struct mft_inode *mi, struct ATTRIB *attr)
 
        asize = le32_to_cpu(attr->size);
 
+       if (!IS_ALIGNED(asize, 8))
+               return NULL;
+
        /* Check overflow and boundary. */
        if (off + asize < off || off + asize > used)
                return NULL;
 
+       /* Can we use the field attr->non_res. */
+       if (off + 9 > used)
+               return NULL;
+
        /* Check size of attribute. */
        if (!attr->non_res) {
                /* Check resident fields. */