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-rw-r--r--fs/ntfs/namei.c392
1 files changed, 0 insertions, 392 deletions
diff --git a/fs/ntfs/namei.c b/fs/ntfs/namei.c
deleted file mode 100644
index d7498ddc4a72..000000000000
--- a/fs/ntfs/namei.c
+++ /dev/null
@@ -1,392 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * namei.c - NTFS kernel directory inode operations. Part of the Linux-NTFS
- * project.
- *
- * Copyright (c) 2001-2006 Anton Altaparmakov
- */
-
-#include <linux/dcache.h>
-#include <linux/exportfs.h>
-#include <linux/security.h>
-#include <linux/slab.h>
-
-#include "attrib.h"
-#include "debug.h"
-#include "dir.h"
-#include "mft.h"
-#include "ntfs.h"
-
-/**
- * ntfs_lookup - find the inode represented by a dentry in a directory inode
- * @dir_ino: directory inode in which to look for the inode
- * @dent: dentry representing the inode to look for
- * @flags: lookup flags
- *
- * In short, ntfs_lookup() looks for the inode represented by the dentry @dent
- * in the directory inode @dir_ino and if found attaches the inode to the
- * dentry @dent.
- *
- * In more detail, the dentry @dent specifies which inode to look for by
- * supplying the name of the inode in @dent->d_name.name. ntfs_lookup()
- * converts the name to Unicode and walks the contents of the directory inode
- * @dir_ino looking for the converted Unicode name. If the name is found in the
- * directory, the corresponding inode is loaded by calling ntfs_iget() on its
- * inode number and the inode is associated with the dentry @dent via a call to
- * d_splice_alias().
- *
- * If the name is not found in the directory, a NULL inode is inserted into the
- * dentry @dent via a call to d_add(). The dentry is then termed a negative
- * dentry.
- *
- * Only if an actual error occurs, do we return an error via ERR_PTR().
- *
- * In order to handle the case insensitivity issues of NTFS with regards to the
- * dcache and the dcache requiring only one dentry per directory, we deal with
- * dentry aliases that only differ in case in ->ntfs_lookup() while maintaining
- * a case sensitive dcache. This means that we get the full benefit of dcache
- * speed when the file/directory is looked up with the same case as returned by
- * ->ntfs_readdir() but that a lookup for any other case (or for the short file
- * name) will not find anything in dcache and will enter ->ntfs_lookup()
- * instead, where we search the directory for a fully matching file name
- * (including case) and if that is not found, we search for a file name that
- * matches with different case and if that has non-POSIX semantics we return
- * that. We actually do only one search (case sensitive) and keep tabs on
- * whether we have found a case insensitive match in the process.
- *
- * To simplify matters for us, we do not treat the short vs long filenames as
- * two hard links but instead if the lookup matches a short filename, we
- * return the dentry for the corresponding long filename instead.
- *
- * There are three cases we need to distinguish here:
- *
- * 1) @dent perfectly matches (i.e. including case) a directory entry with a
- * file name in the WIN32 or POSIX namespaces. In this case
- * ntfs_lookup_inode_by_name() will return with name set to NULL and we
- * just d_splice_alias() @dent.
- * 2) @dent matches (not including case) a directory entry with a file name in
- * the WIN32 namespace. In this case ntfs_lookup_inode_by_name() will return
- * with name set to point to a kmalloc()ed ntfs_name structure containing
- * the properly cased little endian Unicode name. We convert the name to the
- * current NLS code page, search if a dentry with this name already exists
- * and if so return that instead of @dent. At this point things are
- * complicated by the possibility of 'disconnected' dentries due to NFS
- * which we deal with appropriately (see the code comments). The VFS will
- * then destroy the old @dent and use the one we returned. If a dentry is
- * not found, we allocate a new one, d_splice_alias() it, and return it as
- * above.
- * 3) @dent matches either perfectly or not (i.e. we don't care about case) a
- * directory entry with a file name in the DOS namespace. In this case
- * ntfs_lookup_inode_by_name() will return with name set to point to a
- * kmalloc()ed ntfs_name structure containing the mft reference (cpu endian)
- * of the inode. We use the mft reference to read the inode and to find the
- * file name in the WIN32 namespace corresponding to the matched short file
- * name. We then convert the name to the current NLS code page, and proceed
- * searching for a dentry with this name, etc, as in case 2), above.
- *
- * Locking: Caller must hold i_mutex on the directory.
- */
-static struct dentry *ntfs_lookup(struct inode *dir_ino, struct dentry *dent,
- unsigned int flags)
-{
- ntfs_volume *vol = NTFS_SB(dir_ino->i_sb);
- struct inode *dent_inode;
- ntfschar *uname;
- ntfs_name *name = NULL;
- MFT_REF mref;
- unsigned long dent_ino;
- int uname_len;
-
- ntfs_debug("Looking up %pd in directory inode 0x%lx.",
- dent, dir_ino->i_ino);
- /* Convert the name of the dentry to Unicode. */
- uname_len = ntfs_nlstoucs(vol, dent->d_name.name, dent->d_name.len,
- &uname);
- if (uname_len < 0) {
- if (uname_len != -ENAMETOOLONG)
- ntfs_error(vol->sb, "Failed to convert name to "
- "Unicode.");
- return ERR_PTR(uname_len);
- }
- mref = ntfs_lookup_inode_by_name(NTFS_I(dir_ino), uname, uname_len,
- &name);
- kmem_cache_free(ntfs_name_cache, uname);
- if (!IS_ERR_MREF(mref)) {
- dent_ino = MREF(mref);
- ntfs_debug("Found inode 0x%lx. Calling ntfs_iget.", dent_ino);
- dent_inode = ntfs_iget(vol->sb, dent_ino);
- if (!IS_ERR(dent_inode)) {
- /* Consistency check. */
- if (is_bad_inode(dent_inode) || MSEQNO(mref) ==
- NTFS_I(dent_inode)->seq_no ||
- dent_ino == FILE_MFT) {
- /* Perfect WIN32/POSIX match. -- Case 1. */
- if (!name) {
- ntfs_debug("Done. (Case 1.)");
- return d_splice_alias(dent_inode, dent);
- }
- /*
- * We are too indented. Handle imperfect
- * matches and short file names further below.
- */
- goto handle_name;
- }
- ntfs_error(vol->sb, "Found stale reference to inode "
- "0x%lx (reference sequence number = "
- "0x%x, inode sequence number = 0x%x), "
- "returning -EIO. Run chkdsk.",
- dent_ino, MSEQNO(mref),
- NTFS_I(dent_inode)->seq_no);
- iput(dent_inode);
- dent_inode = ERR_PTR(-EIO);
- } else
- ntfs_error(vol->sb, "ntfs_iget(0x%lx) failed with "
- "error code %li.", dent_ino,
- PTR_ERR(dent_inode));
- kfree(name);
- /* Return the error code. */
- return ERR_CAST(dent_inode);
- }
- /* It is guaranteed that @name is no longer allocated at this point. */
- if (MREF_ERR(mref) == -ENOENT) {
- ntfs_debug("Entry was not found, adding negative dentry.");
- /* The dcache will handle negative entries. */
- d_add(dent, NULL);
- ntfs_debug("Done.");
- return NULL;
- }
- ntfs_error(vol->sb, "ntfs_lookup_ino_by_name() failed with error "
- "code %i.", -MREF_ERR(mref));
- return ERR_PTR(MREF_ERR(mref));
- // TODO: Consider moving this lot to a separate function! (AIA)
-handle_name:
- {
- MFT_RECORD *m;
- ntfs_attr_search_ctx *ctx;
- ntfs_inode *ni = NTFS_I(dent_inode);
- int err;
- struct qstr nls_name;
-
- nls_name.name = NULL;
- if (name->type != FILE_NAME_DOS) { /* Case 2. */
- ntfs_debug("Case 2.");
- nls_name.len = (unsigned)ntfs_ucstonls(vol,
- (ntfschar*)&name->name, name->len,
- (unsigned char**)&nls_name.name, 0);
- kfree(name);
- } else /* if (name->type == FILE_NAME_DOS) */ { /* Case 3. */
- FILE_NAME_ATTR *fn;
-
- ntfs_debug("Case 3.");
- kfree(name);
-
- /* Find the WIN32 name corresponding to the matched DOS name. */
- ni = NTFS_I(dent_inode);
- m = map_mft_record(ni);
- if (IS_ERR(m)) {
- err = PTR_ERR(m);
- m = NULL;
- ctx = NULL;
- goto err_out;
- }
- ctx = ntfs_attr_get_search_ctx(ni, m);
- if (unlikely(!ctx)) {
- err = -ENOMEM;
- goto err_out;
- }
- do {
- ATTR_RECORD *a;
- u32 val_len;
-
- err = ntfs_attr_lookup(AT_FILE_NAME, NULL, 0, 0, 0,
- NULL, 0, ctx);
- if (unlikely(err)) {
- ntfs_error(vol->sb, "Inode corrupt: No WIN32 "
- "namespace counterpart to DOS "
- "file name. Run chkdsk.");
- if (err == -ENOENT)
- err = -EIO;
- goto err_out;
- }
- /* Consistency checks. */
- a = ctx->attr;
- if (a->non_resident || a->flags)
- goto eio_err_out;
- val_len = le32_to_cpu(a->data.resident.value_length);
- if (le16_to_cpu(a->data.resident.value_offset) +
- val_len > le32_to_cpu(a->length))
- goto eio_err_out;
- fn = (FILE_NAME_ATTR*)((u8*)ctx->attr + le16_to_cpu(
- ctx->attr->data.resident.value_offset));
- if ((u32)(fn->file_name_length * sizeof(ntfschar) +
- sizeof(FILE_NAME_ATTR)) > val_len)
- goto eio_err_out;
- } while (fn->file_name_type != FILE_NAME_WIN32);
-
- /* Convert the found WIN32 name to current NLS code page. */
- nls_name.len = (unsigned)ntfs_ucstonls(vol,
- (ntfschar*)&fn->file_name, fn->file_name_length,
- (unsigned char**)&nls_name.name, 0);
-
- ntfs_attr_put_search_ctx(ctx);
- unmap_mft_record(ni);
- }
- m = NULL;
- ctx = NULL;
-
- /* Check if a conversion error occurred. */
- if ((signed)nls_name.len < 0) {
- err = (signed)nls_name.len;
- goto err_out;
- }
- nls_name.hash = full_name_hash(dent, nls_name.name, nls_name.len);
-
- dent = d_add_ci(dent, dent_inode, &nls_name);
- kfree(nls_name.name);
- return dent;
-
-eio_err_out:
- ntfs_error(vol->sb, "Illegal file name attribute. Run chkdsk.");
- err = -EIO;
-err_out:
- if (ctx)
- ntfs_attr_put_search_ctx(ctx);
- if (m)
- unmap_mft_record(ni);
- iput(dent_inode);
- ntfs_error(vol->sb, "Failed, returning error code %i.", err);
- return ERR_PTR(err);
- }
-}
-
-/*
- * Inode operations for directories.
- */
-const struct inode_operations ntfs_dir_inode_ops = {
- .lookup = ntfs_lookup, /* VFS: Lookup directory. */
-};
-
-/**
- * ntfs_get_parent - find the dentry of the parent of a given directory dentry
- * @child_dent: dentry of the directory whose parent directory to find
- *
- * Find the dentry for the parent directory of the directory specified by the
- * dentry @child_dent. This function is called from
- * fs/exportfs/expfs.c::find_exported_dentry() which in turn is called from the
- * default ->decode_fh() which is export_decode_fh() in the same file.
- *
- * The code is based on the ext3 ->get_parent() implementation found in
- * fs/ext3/namei.c::ext3_get_parent().
- *
- * Note: ntfs_get_parent() is called with @d_inode(child_dent)->i_mutex down.
- *
- * Return the dentry of the parent directory on success or the error code on
- * error (IS_ERR() is true).
- */
-static struct dentry *ntfs_get_parent(struct dentry *child_dent)
-{
- struct inode *vi = d_inode(child_dent);
- ntfs_inode *ni = NTFS_I(vi);
- MFT_RECORD *mrec;
- ntfs_attr_search_ctx *ctx;
- ATTR_RECORD *attr;
- FILE_NAME_ATTR *fn;
- unsigned long parent_ino;
- int err;
-
- ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
- /* Get the mft record of the inode belonging to the child dentry. */
- mrec = map_mft_record(ni);
- if (IS_ERR(mrec))
- return ERR_CAST(mrec);
- /* Find the first file name attribute in the mft record. */
- ctx = ntfs_attr_get_search_ctx(ni, mrec);
- if (unlikely(!ctx)) {
- unmap_mft_record(ni);
- return ERR_PTR(-ENOMEM);
- }
-try_next:
- err = ntfs_attr_lookup(AT_FILE_NAME, NULL, 0, CASE_SENSITIVE, 0, NULL,
- 0, ctx);
- if (unlikely(err)) {
- ntfs_attr_put_search_ctx(ctx);
- unmap_mft_record(ni);
- if (err == -ENOENT)
- ntfs_error(vi->i_sb, "Inode 0x%lx does not have a "
- "file name attribute. Run chkdsk.",
- vi->i_ino);
- return ERR_PTR(err);
- }
- attr = ctx->attr;
- if (unlikely(attr->non_resident))
- goto try_next;
- fn = (FILE_NAME_ATTR *)((u8 *)attr +
- le16_to_cpu(attr->data.resident.value_offset));
- if (unlikely((u8 *)fn + le32_to_cpu(attr->data.resident.value_length) >
- (u8*)attr + le32_to_cpu(attr->length)))
- goto try_next;
- /* Get the inode number of the parent directory. */
- parent_ino = MREF_LE(fn->parent_directory);
- /* Release the search context and the mft record of the child. */
- ntfs_attr_put_search_ctx(ctx);
- unmap_mft_record(ni);
-
- return d_obtain_alias(ntfs_iget(vi->i_sb, parent_ino));
-}
-
-static struct inode *ntfs_nfs_get_inode(struct super_block *sb,
- u64 ino, u32 generation)
-{
- struct inode *inode;
-
- inode = ntfs_iget(sb, ino);
- if (!IS_ERR(inode)) {
- if (is_bad_inode(inode) || inode->i_generation != generation) {
- iput(inode);
- inode = ERR_PTR(-ESTALE);
- }
- }
-
- return inode;
-}
-
-static struct dentry *ntfs_fh_to_dentry(struct super_block *sb, struct fid *fid,
- int fh_len, int fh_type)
-{
- return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
- ntfs_nfs_get_inode);
-}
-
-static struct dentry *ntfs_fh_to_parent(struct super_block *sb, struct fid *fid,
- int fh_len, int fh_type)
-{
- return generic_fh_to_parent(sb, fid, fh_len, fh_type,
- ntfs_nfs_get_inode);
-}
-
-/*
- * Export operations allowing NFS exporting of mounted NTFS partitions.
- *
- * We use the default ->encode_fh() for now. Note that they
- * use 32 bits to store the inode number which is an unsigned long so on 64-bit
- * architectures is usually 64 bits so it would all fail horribly on huge
- * volumes. I guess we need to define our own encode and decode fh functions
- * that store 64-bit inode numbers at some point but for now we will ignore the
- * problem...
- *
- * We also use the default ->get_name() helper (used by ->decode_fh() via
- * fs/exportfs/expfs.c::find_exported_dentry()) as that is completely fs
- * independent.
- *
- * The default ->get_parent() just returns -EACCES so we have to provide our
- * own and the default ->get_dentry() is incompatible with NTFS due to not
- * allowing the inode number 0 which is used in NTFS for the system file $MFT
- * and due to using iget() whereas NTFS needs ntfs_iget().
- */
-const struct export_operations ntfs_export_ops = {
- .encode_fh = generic_encode_ino32_fh,
- .get_parent = ntfs_get_parent, /* Find the parent of a given
- directory. */
- .fh_to_dentry = ntfs_fh_to_dentry,
- .fh_to_parent = ntfs_fh_to_parent,
-};
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