linux-stable.git/fs/ntfs/dir.c, branch master

ntfs: fix NULL dereference in ntfs_index_walk_down()

2026-04-27T13:29:04+00:00

ntfs_index_walk_down() allocates ictx->ib when descending from the root
into an index allocation block. If that allocation fails, the old code
still passes the NULL buffer to ntfs_ib_read(), which can write through
it via ntfs_inode_attr_pread().

Allocate the index block into a temporary pointer and return -ENOMEM
before changing the index context on allocation failure. Also propagate
ERR_PTR() through ntfs_index_next() and ntfs_readdir() so walk-down
allocation or index block read failures are not mistaken for normal
index iteration inside the filesystem.

ntfs_readdir() keeps the existing userspace-visible behavior of
suppressing readdir errors after marking end_in_iterate; this change only
prevents the walk-down failure path from dereferencing NULL internally.

The failure was reproduced with failslab fail-nth injection on getdents64;
the original module hits a NULL pointer dereference in memcpy_orig through
ntfs_ib_read(), while the patched module reaches the same
ntfs_index_walk_down() allocation failure without crashing.

Fixes: 0a8ac0c1fa0b ("ntfs: update directory operations")
Signed-off-by: DaeMyung Kang 
Reviewed-by: Hyunchul Lee 
Signed-off-by: Namjae Jeon

ntfs: fix variable dereferenced before check warnings

2026-03-16T11:27:45+00:00

Detected by Smatch.

lcnalloc.c:736 ntfs_cluster_alloc() error:
  we previously assumed 'rl' could be null (see line 719)

inode.c:3275 ntfs_inode_close() warn:
  variable dereferenced before check 'tmp_nis' (see line 3255)

attrib.c:4952 ntfs_attr_remove() warn:
  variable dereferenced before check 'ni' (see line 4951)

dir.c:1035 ntfs_readdir() error:
  we previously assumed 'private' could be null (see line 850)

Signed-off-by: Hyunchul Lee 
Signed-off-by: Namjae Jeon

ntfs: prefer IS_ERR_OR_NULL() over manual NULL check

2026-03-16T11:27:42+00:00

Use IS_ERR_OR_NULL() instead of manual NULL and IS_ERR() checks.

Signed-off-by: Hyunchul Lee 
Signed-off-by: Namjae Jeon

ntfs: use ->mft_no instead of ->i_ino in prints

2026-03-06T13:08:42+00:00

This improves log accuracy for NTFS debugging and removes unnecessary
reliance on the VFS i_ino field ahead of the core VFS type change.

Signed-off-by: Namjae Jeon

ntfs: change mft_no type to u64

2026-03-06T13:08:39+00:00

Changes the type of ntfs_inode::mft_no from unsigned long to u64
to safely handle the full 48-bit range without truncation risk, especially
in preparation for broader VFS inode number type (i_ino:u64) and to
improve consistency with ntfs driver practices.

Signed-off-by: Namjae Jeon

ntfs: update directory operations

2026-02-19T12:48:07+00:00

Update the directory and index operations to support full read-write
functionality and use the folio API, including directory modification.

Acked-by: Christoph Hellwig 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Namjae Jeon

Revert "fs: Remove NTFS classic"

2026-02-19T12:48:05+00:00

This reverts commit 7ffa8f3d30236e0ab897c30bdb01224ff1fe1c89.

Reverts the removal of the classic read-only ntfs driver to
serve as the base for a new read-write ntfs implementation.
If we stack changes on top of the revert patch, It will significantly
reduce the diff size, making the review easier.

This revert intentionally excludes the restoration of Kconfig and
Makefile. The Kconfig and Makefile will be added back in the final patch
of this series, enabling the driver only after all features and
improvements have been applied.

Acked-by: Christoph Hellwig 
Signed-off-by: Namjae Jeon

fs: Remove NTFS classic

2024-01-24T09:47:00+00:00

The replacement, NTFS3, was merged over two years ago.  It is now time to
remove the original from the tree as it is the last user of several APIs,
and it is not worth changing.

Signed-off-by: Matthew Wilcox (Oracle) 
Link: https://lore.kernel.org/r/20240115072025.2071931-1-willy@infradead.org
Acked-by: Namjae Jeon 
Acked-by: Dave Chinner 
Cc: Anton Altaparmakov 
Cc: Namjae Jeon 
Signed-off-by: Christian Brauner

ntfs: dir.c: fix kernel-doc function parameter warnings

2023-12-21T12:17:54+00:00

Correct the kernel-doc function parameter warnings for function
ntfs_dir_fsync() to prevent the following kernel-doc warnings:

dir.c:1489: warning: Function parameter or member 'start' not described in 'ntfs_dir_fsync'
dir.c:1489: warning: Function parameter or member 'end' not described in 'ntfs_dir_fsync'
dir.c:1489: warning: Excess function parameter 'dentry' description in 'ntfs_dir_fsync'

Signed-off-by: Randy Dunlap 
Link: https://lore.kernel.org/r/20231219045414.24670-1-rdunlap@infradead.org
Reviewed-by: Namjae Jeon 
Cc: Anton Altaparmakov 
Cc: Namjae Jeon 
Cc: 
Cc: Andrew Morton 
Signed-off-by: Christian Brauner

vfs: get rid of old '->iterate' directory operation

2023-08-06T13:08:35+00:00

All users now just use '->iterate_shared()', which only takes the
directory inode lock for reading.

Filesystems that never got convered to shared mode now instead use a
wrapper that drops the lock, re-takes it in write mode, calls the old
function, and then downgrades the lock back to read mode.

This way the VFS layer and other callers no longer need to care about
filesystems that never got converted to the modern era.

The filesystems that use the new wrapper are ceph, coda, exfat, jfs,
ntfs, ocfs2, overlayfs, and vboxsf.

Honestly, several of them look like they really could just iterate their
directories in shared mode and skip the wrapper entirely, but the point
of this change is to not change semantics or fix filesystems that
haven't been fixed in the last 7+ years, but to finally get rid of the
dual iterators.

Signed-off-by: Linus Torvalds 
Signed-off-by: Christian Brauner