diff options
| author | Moon Hee Lee <moonhee.lee.ca@gmail.com> | 2025-07-22 10:40:16 -0700 |
|---|---|---|
| committer | Konstantin Komarov <almaz.alexandrovich@paragon-software.com> | 2025-09-10 11:01:41 +0200 |
| commit | 0dc7117da8f92dd5fe077d712a756eccbe377d40 (patch) | |
| tree | e1af248c06dae23e2e598b0726bdd26fccb818c5 /fs/ntfs3 | |
| parent | d68318471aa2e16222ebf492883e05a2d72b9b17 (diff) | |
fs/ntfs3: reject index allocation if $BITMAP is empty but blocks exist
Index allocation requires at least one bit in the $BITMAP attribute to
track usage of index entries. If the bitmap is empty while index blocks
are already present, this reflects on-disk corruption.
syzbot triggered this condition using a malformed NTFS image. During a
rename() operation involving a long filename (which spans multiple
index entries), the empty bitmap allowed the name to be added without
valid tracking. Subsequent deletion of the original entry failed with
-ENOENT, due to unexpected index state.
Reject such cases by verifying that the bitmap is not empty when index
blocks exist.
Reported-by: syzbot+b0373017f711c06ada64@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b0373017f711c06ada64
Fixes: d99208b91933 ("fs/ntfs3: cancle set bad inode after removing name fails")
Tested-by: syzbot+b0373017f711c06ada64@syzkaller.appspotmail.com
Signed-off-by: Moon Hee Lee <moonhee.lee.ca@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Diffstat (limited to 'fs/ntfs3')
| -rw-r--r-- | fs/ntfs3/index.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/fs/ntfs3/index.c b/fs/ntfs3/index.c index 1bf2a6593dec..6d1bf890929d 100644 --- a/fs/ntfs3/index.c +++ b/fs/ntfs3/index.c @@ -1508,6 +1508,16 @@ static int indx_add_allocate(struct ntfs_index *indx, struct ntfs_inode *ni, bmp_size = bmp_size_v = le32_to_cpu(bmp->res.data_size); } + /* + * Index blocks exist, but $BITMAP has zero valid bits. + * This implies an on-disk corruption and must be rejected. + */ + if (in->name == I30_NAME && + unlikely(bmp_size_v == 0 && indx->alloc_run.count)) { + err = -EINVAL; + goto out1; + } + bit = bmp_size << 3; } |