kernel/git/stable/linux.git/fs/file_attr.c, branch master

fs: Add case sensitivity flags to file_kattr

2026-05-11T14:50:27+00:00

Enable upper layers such as NFSD to retrieve case sensitivity information from file systems by adding FS_XFLAG_CASEFOLD and FS_XFLAG_CASENONPRESERVING flags. Filesystems report case-insensitive or case-nonpreserving behavior by setting these flags directly in fa->fsx_xflags. The default (flags unset) indicates POSIX semantics: case-sensitive and case-preserving. Both flags are added to FS_XFLAG_RDONLY_MASK so FS_IOC_FSSETXATTR silently strips them, keeping the new xflags strictly a reporting interface. Callers that want to toggle casefolding continue to use FS_IOC_SETFLAGS with FS_CASEFOLD_FL, the established UAPI on filesystems that support the operation (ext4 and f2fs on empty directories). Case sensitivity information is exported to userspace via the fa_xflags field in the FS_IOC_FSGETXATTR ioctl and file_getattr() system call. Reviewed-by: "Darrick J. Wong" Reviewed-by: Jan Kara Reviewed-by: Roland Mainz Signed-off-by: Chuck Lever Link: https://patch.msgid.link/20260507-case-sensitivity-v14-2-e62cc8200435@oracle.com Signed-off-by: Christian Brauner

fs: Move file_kattr initialization to callers

2026-05-11T14:50:27+00:00

fileattr_fill_xflags() and fileattr_fill_flags() memset the entire file_kattr struct before populating select fields, so callers cannot pre-set fields in fa->fsx_xflags without having their values clobbered. Darrick Wong noted that a function named "fill_xflags" touching more than xflags forces callers to know implementation details beyond its apparent scope. Drop the memset from both fill functions and initialize at the entry points instead: ioctl_setflags(), ioctl_fssetxattr(), the file_setattr() syscall, and xfs_ioc_fsgetxattra() now declare fa with an aggregate initializer. ioctl_getflags(), ioctl_fsgetxattr(), and the file_getattr() syscall already aggregate-initialize fa to pass flags_valid/fsx_valid hints into vfs_fileattr_get(). Subsequent patches rely on this so that ->fileattr_get() handlers can set case-sensitivity flags (FS_XFLAG_CASEFOLD, FS_XFLAG_CASENONPRESERVING) in fa->fsx_xflags before the fill functions run. Suggested-by: Darrick J. Wong Reviewed-by: Jan Kara Reviewed-by: Darrick J. Wong Reviewed-by: Roland Mainz Signed-off-by: Chuck Lever Link: https://patch.msgid.link/20260507-case-sensitivity-v14-1-e62cc8200435@oracle.com Reviewed-by: "Darrick J. Wong" Signed-off-by: Christian Brauner

Merge tag 'vfs-7.0-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-02-25T18:34:23+00:00

Pull vfs fixes from Christian Brauner: - Fix an uninitialized variable in file_getattr(). The flags_valid field wasn't initialized before calling vfs_fileattr_get(), triggering KMSAN uninit-value reports in fuse - Fix writeback wakeup and logging timeouts when DETECT_HUNG_TASK is not enabled. sysctl_hung_task_timeout_secs is 0 in that case causing spurious "waiting for writeback completion for more than 1 seconds" warnings - Fix a null-ptr-deref in do_statmount() when the mount is internal - Add missing kernel-doc description for the @private parameter in iomap_readahead() - Fix mount namespace creation to hold namespace_sem across the mount copy in create_new_namespace(). The previous drop-and-reacquire pattern was fragile and failed to clean up mount propagation links if the real rootfs was a shared or dependent mount - Fix /proc mount iteration where m->index wasn't updated when m->show() overflows, causing a restart to repeatedly show the same mount entry in a rapidly expanding mount table - Return EFSCORRUPTED instead of ENOSPC in minix_new_inode() when the inode number is out of range - Fix unshare(2) when CLONE_NEWNS is set and current->fs isn't shared. copy_mnt_ns() received the live fs_struct so if a subsequent namespace creation failed the rollback would leave pwd and root pointing to detached mounts. Always allocate a new fs_struct when CLONE_NEWNS is requested - fserror bug fixes: - Remove the unused fsnotify_sb_error() helper now that all callers have been converted to fserror_report_metadata - Fix a lockdep splat in fserror_report() where igrab() takes inode::i_lock which can be held in IRQ context. Replace igrab() with a direct i_count bump since filesystems should not report inodes that are about to be freed or not yet exposed - Handle error pointer in procfs for try_lookup_noperm() - Fix an integer overflow in ep_loop_check_proc() where recursive calls returning INT_MAX would overflow when +1 is added, breaking the recursion depth check - Fix a misleading break in pidfs * tag 'vfs-7.0-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: pidfs: avoid misleading break eventpoll: Fix integer overflow in ep_loop_check_proc() proc: Fix pointer error dereference fserror: fix lockdep complaint when igrabbing inode fsnotify: drop unused helper unshare: fix unshare_fs() handling minix: Correct errno in minix_new_inode namespace: fix proc mount iteration mount: hold namespace_sem across copy in create_new_namespace() iomap: Describe @private in iomap_readahead() statmount: Fix the null-ptr-deref in do_statmount() writeback: Fix wakeup and logging timeouts for !DETECT_HUNG_TASK fs: init flags_valid before calling vfs_fileattr_get

Merge tag 'vfs-7.0-rc1.misc.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-02-16T21:00:36+00:00

Pull more misc vfs updates from Christian Brauner: "Features: - Optimize close_range() from O(range size) to O(active FDs) by using find_next_bit() on the open_fds bitmap instead of linearly scanning the entire requested range. This is a significant improvement for large-range close operations on sparse file descriptor tables. - Add FS_XFLAG_VERITY file attribute for fs-verity files, retrievable via FS_IOC_FSGETXATTR and file_getattr(). The flag is read-only. Add tracepoints for fs-verity enable and verify operations, replacing the previously removed debug printk's. - Prevent nfsd from exporting special kernel filesystems like pidfs and nsfs. These filesystems have custom ->open() and ->permission() export methods that are designed for open_by_handle_at(2) only and are incompatible with nfsd. Update the exportfs documentation accordingly. Fixes: - Fix KMSAN uninit-value in ovl_fill_real() where strcmp() was used on a non-null-terminated decrypted directory entry name from fscrypt. This triggered on encrypted lower layers when the decrypted name buffer contained uninitialized tail data. The fix also adds VFS-level name_is_dot(), name_is_dotdot(), and name_is_dot_dotdot() helpers, replacing various open-coded "." and ".." checks across the tree. - Fix read-only fsflags not being reset together with xflags in vfs_fileattr_set(). Currently harmless since no read-only xflags overlap with flags, but this would cause inconsistencies for any future shared read-only flag - Return -EREMOTE instead of -ESRCH from PIDFD_GET_INFO when the target process is in a different pid namespace. This lets userspace distinguish "process exited" from "process in another namespace", matching glibc's pidfd_getpid() behavior Cleanups: - Use C-string literals in the Rust seq_file bindings, replacing the kernel::c_str!() macro (available since Rust 1.77) - Fix typo in d_walk_ret enum comment, add porting notes for the readlink_copy() calling convention change" * tag 'vfs-7.0-rc1.misc.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: add porting notes about readlink_copy() pidfs: return -EREMOTE when PIDFD_GET_INFO is called on another ns nfsd: do not allow exporting of special kernel filesystems exportfs: clarify the documentation of open()/permission() expotrfs ops fsverity: add tracepoints fs: add FS_XFLAG_VERITY for fs-verity files rust: seq_file: replace `kernel::c_str!` with C-Strings fs: dcache: fix typo in enum d_walk_ret comment ovl: use name_is_dot* helpers in readdir code fs: add helpers name_is_dot{,dot,_dotdot} ovl: Fix uninit-value in ovl_fill_real fs: reset read-only fsflags together with xflags fs/file: optimize close_range() complexity from O(N) to O(Sparse)

fs: init flags_valid before calling vfs_fileattr_get

2026-02-14T12:17:43+00:00

syzbot reported a uninit-value bug in [1]. Similar to the "*get" context where the kernel's internal file_kattr structure is initialized before calling vfs_fileattr_get(), we should use the same mechanism when using fa. [1] BUG: KMSAN: uninit-value in fuse_fileattr_get+0xeb4/0x1450 fs/fuse/ioctl.c:517 fuse_fileattr_get+0xeb4/0x1450 fs/fuse/ioctl.c:517 vfs_fileattr_get fs/file_attr.c:94 [inline] __do_sys_file_getattr fs/file_attr.c:416 [inline] Local variable fa.i created at: __do_sys_file_getattr fs/file_attr.c:380 [inline] __se_sys_file_getattr+0x8c/0xbd0 fs/file_attr.c:372 Reported-by: syzbot+7c31755f2cea07838b0c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=7c31755f2cea07838b0c Tested-by: syzbot+7c31755f2cea07838b0c@syzkaller.appspotmail.com Signed-off-by: Edward Adam Davis Link: https://patch.msgid.link/tencent_B6C4583771D76766D71362A368696EC3B605@qq.com Signed-off-by: Christian Brauner

fs: add FS_XFLAG_VERITY for fs-verity files

2026-01-29T15:00:57+00:00

fs-verity introduced inode flag for inodes with enabled fs-verity on them. This patch adds FS_XFLAG_VERITY file attribute which can be retrieved with FS_IOC_FSGETXATTR ioctl() and file_getattr() syscall. This flag is read-only and can not be set with corresponding set ioctl() and file_setattr(). The FS_IOC_SETFLAGS requires file to be opened for writing which is not allowed for verity files. The FS_IOC_FSSETXATTR and file_setattr() clears this flag from the user input. As this is now common flag for both flag interfaces (flags/xflags) add it to overlapping flags list to exclude it from overwrite. Signed-off-by: Andrey Albershteyn Link: https://patch.msgid.link/20260126115658.27656-2-aalbersh@kernel.org Reviewed-by: Darrick J. Wong Signed-off-by: Christian Brauner

fs: reset read-only fsflags together with xflags

2026-01-23T14:55:40+00:00

While setting file attributes, the read-only flags are reset for ->xflags, but not for ->flags if flag is shared between both. This is fine for now as all read-only xflags don't overlap with flags. However, for any read-only shared flag this will create inconsistency between xflags and flags. The non-shared flag will be reset in vfs_fileattr_set() to the current value, but shared one is past further to ->fileattr_set. Reported-by: Eric Biggers Signed-off-by: Andrey Albershteyn Link: https://patch.msgid.link/20260121193645.3611716-1-aalbersh@kernel.org Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

file_[gs]etattr(2): switch to CLASS(filename_maybe_null)

2026-01-16T17:52:03+00:00

Signed-off-by: Al Viro

file_setattr(): filename_lookup() accepts ERR_PTR() as filename

2026-01-13T20:18:07+00:00

no need to check it in the caller Signed-off-by: Al Viro

file_getattr(): filename_lookup() accepts ERR_PTR() as filename

2026-01-13T20:18:07+00:00

no need to check it in the caller Signed-off-by: Al Viro