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

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)

Author: torvalds

Documentation/filesystems/fsverity.rst

@@ -341,6 +341,22 @@ the file has fs-verity enabled.  This can perform better than
 FS_IOC_GETFLAGS and FS_IOC_MEASURE_VERITY because it doesn't require
 opening the file, and opening verity files can be expensive.
 
+FS_IOC_FSGETXATTR
+-----------------
+
+Since Linux v7.0, the FS_IOC_FSGETXATTR ioctl sets FS_XFLAG_VERITY (0x00020000)
+in the returned flags when the file has verity enabled. Note that this attribute
+cannot be set with FS_IOC_FSSETXATTR as enabling verity requires input
+parameters. See FS_IOC_ENABLE_VERITY.
+
+file_getattr
+------------
+
+Since Linux v7.0, the file_getattr() syscall sets FS_XFLAG_VERITY (0x00020000)
+in the returned flags when the file has verity enabled. Note that this attribute
+cannot be set with file_setattr() as enabling verity requires input parameters.
+See FS_IOC_ENABLE_VERITY.
+
 .. _accessing_verity_files:
 
 Accessing verity files

Documentation/filesystems/porting.rst

@@ -1351,3 +1351,13 @@ and do_rmdir()) are gone; they are replaced with non-consuming analogues
 (filename_renameat2(), etc.)
 Callers are adjusted - responsibility for dropping the filenames belongs
 to them now.
+
+---
+
+**mandatory**
+
+readlink_copy() now requires link length as the 4th argument. Said length needs
+to match what strlen() would return if it was ran on the string.
+
+However, if the string is freely accessible for the duration of inode's
+lifetime, consider using inode_set_cached_link() instead.

MAINTAINERS

@@ -10415,6 +10415,7 @@ T:	git https://git.kernel.org/pub/scm/fs/fsverity/linux.git
 F:	Documentation/filesystems/fsverity.rst
 F:	fs/verity/
 F:	include/linux/fsverity.h
+F:	include/trace/events/fsverity.h
 F:	include/uapi/linux/fsverity.h
 
 FT260 FTDI USB-HID TO I2C BRIDGE DRIVER

fs/crypto/fname.c

@@ -76,7 +76,7 @@ struct fscrypt_nokey_name {
 
 static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
 {
-	return is_dot_dotdot(str->name, str->len);
+	return name_is_dot_dotdot(str->name, str->len);
 }
 
 /**

fs/dcache.c

@@ -1298,8 +1298,8 @@ void shrink_dcache_sb(struct super_block *sb)
 EXPORT_SYMBOL(shrink_dcache_sb);
 
 /**
- * enum d_walk_ret - action to talke during tree walk
- * @D_WALK_CONTINUE:	contrinue walk
+ * enum d_walk_ret - action to take during tree walk
+ * @D_WALK_CONTINUE:	continue walk
  * @D_WALK_QUIT:	quit walk
  * @D_WALK_NORETRY:	quit when retry is needed
  * @D_WALK_SKIP:	skip this dentry and its children
@@ -1722,7 +1722,7 @@ void d_invalidate(struct dentry *dentry)
 EXPORT_SYMBOL(d_invalidate);
 
 /**
- * __d_alloc	-	allocate a dcache entry
+ * __d_alloc - allocate a dcache entry
  * @sb: filesystem it will belong to
  * @name: qstr of the name
  *
@@ -1806,7 +1806,7 @@ static struct dentry *__d_alloc(struct super_block *sb, const struct qstr *name)
 }
 
 /**
- * d_alloc	-	allocate a dcache entry
+ * d_alloc - allocate a dcache entry
  * @parent: parent of entry to allocate
  * @name: qstr of the name
  *
@@ -2546,7 +2546,7 @@ static void __d_rehash(struct dentry *entry)
 }
 
 /**
- * d_rehash	- add an entry back to the hash
+ * d_rehash - add an entry back to the hash
  * @entry: dentry to add to the hash
  *
  * Adds a dentry to the hash according to its name.

fs/ecryptfs/crypto.c

@@ -1904,7 +1904,7 @@ int ecryptfs_decode_and_decrypt_filename(char **plaintext_name,
 
 	if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) &&
 	    !(mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)) {
-		if (is_dot_dotdot(name, name_size)) {
+		if (name_is_dot_dotdot(name, name_size)) {
 			rc = ecryptfs_copy_filename(plaintext_name,
 						    plaintext_name_size,
 						    name, name_size);

fs/exportfs/expfs.c

@@ -253,7 +253,8 @@ static bool filldir_one(struct dir_context *ctx, const char *name, int len,
 		container_of(ctx, struct getdents_callback, ctx);
 
 	buf->sequence++;
-	if (buf->ino == ino && len <= NAME_MAX && !is_dot_dotdot(name, len)) {
+	if (buf->ino == ino && len <= NAME_MAX &&
+	    !name_is_dot_dotdot(name, len)) {
 		memcpy(buf->name, name, len);
 		buf->name[len] = '\0';
 		buf->found = 1;

fs/f2fs/dir.c

@@ -68,7 +68,7 @@ int f2fs_init_casefolded_name(const struct inode *dir,
 	int len;
 
 	if (IS_CASEFOLDED(dir) &&
-	    !is_dot_dotdot(fname->usr_fname->name, fname->usr_fname->len)) {
+	    !name_is_dot_dotdot(fname->usr_fname->name, fname->usr_fname->len)) {
 		buf = f2fs_kmem_cache_alloc(f2fs_cf_name_slab,
 					    GFP_NOFS, false, F2FS_SB(sb));
 		if (!buf)

fs/f2fs/hash.c

@@ -100,7 +100,7 @@ void f2fs_hash_filename(const struct inode *dir, struct f2fs_filename *fname)
 
 	WARN_ON_ONCE(!name);
 
-	if (is_dot_dotdot(name, len)) {
+	if (name_is_dot_dotdot(name, len)) {
 		fname->hash = 0;
 		return;
 	}

fs/file.c

@@ -777,23 +777,29 @@ static inline void __range_close(struct files_struct *files, unsigned int fd,
 				 unsigned int max_fd)
 {
 	struct file *file;
+	struct fdtable *fdt;
 	unsigned n;
 
 	spin_lock(&files->file_lock);
-	n = last_fd(files_fdtable(files));
+	fdt = files_fdtable(files);
+	n = last_fd(fdt);
 	max_fd = min(max_fd, n);
 
-	for (; fd <= max_fd; fd++) {
+	for (fd = find_next_bit(fdt->open_fds, max_fd + 1, fd);
+	     fd <= max_fd;
+	     fd = find_next_bit(fdt->open_fds, max_fd + 1, fd + 1)) {
 		file = file_close_fd_locked(files, fd);
 		if (file) {
 			spin_unlock(&files->file_lock);
 			filp_close(file, files);
 			cond_resched();
 			spin_lock(&files->file_lock);
+			fdt = files_fdtable(files);
 		} else if (need_resched()) {
 			spin_unlock(&files->file_lock);
 			cond_resched();
 			spin_lock(&files->file_lock);
+			fdt = files_fdtable(files);
 		}
 	}
 	spin_unlock(&files->file_lock);