2022-04-27 11:32 GMT+09:00, Namjae Jeon <linkinjeon@xxxxxxxxxx>:
Hi Al,
Could you please review this patch-set ?
Thanks!
> Al pointed out that ksmbd has racy issue from using ->d_parent and ->d_name
> in ksmbd_vfs_unlink and smb2_vfs_rename(). and use new lock_rename_child()
> to lock stable parent while underlying rename racy.
> Introduce vfs_path_parent_lookup helper to avoid out of share access and
> export vfs functions like the following ones to use
> vfs_path_parent_lookup().
> - export __lookup_hash().
> - export getname_kernel() and putname().
>
> vfs_path_parent_lookup() is used for parent lookup of destination file
> using absolute pathname given from FILE_RENAME_INFORMATION request.
>
> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
> Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
> ---
> fs/ksmbd/smb2pdu.c | 105 ++-------------
> fs/ksmbd/vfs.c | 302 ++++++++++++++++--------------------------
> fs/ksmbd/vfs.h | 10 +-
> fs/ksmbd/vfs_cache.c | 5 +-
> fs/namei.c | 41 +++++-
> include/linux/namei.h | 5 +
> 6 files changed, 172 insertions(+), 296 deletions(-)
>
> diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
> index 16c803a9d996..d3e29f60fa2e 100644
> --- a/fs/ksmbd/smb2pdu.c
> +++ b/fs/ksmbd/smb2pdu.c
> @@ -5362,44 +5362,19 @@ int smb2_echo(struct ksmbd_work *work)
>
> static int smb2_rename(struct ksmbd_work *work,
> struct ksmbd_file *fp,
> - struct user_namespace *user_ns,
> struct smb2_file_rename_info *file_info,
> struct nls_table *local_nls)
> {
> struct ksmbd_share_config *share = fp->tcon->share_conf;
> - char *new_name = NULL, *abs_oldname = NULL, *old_name = NULL;
> - char *pathname = NULL;
> - struct path path;
> - bool file_present = true;
> - int rc;
> + char *new_name = NULL;
> + int rc, flags = 0;
>
> ksmbd_debug(SMB, "setting FILE_RENAME_INFO\n");
> - pathname = kmalloc(PATH_MAX, GFP_KERNEL);
> - if (!pathname)
> - return -ENOMEM;
> -
> - abs_oldname = d_path(&fp->filp->f_path, pathname, PATH_MAX);
> - if (IS_ERR(abs_oldname)) {
> - rc = -EINVAL;
> - goto out;
> - }
> - old_name = strrchr(abs_oldname, '/');
> - if (old_name && old_name[1] != '\0') {
> - old_name++;
> - } else {
> - ksmbd_debug(SMB, "can't get last component in path %s\n",
> - abs_oldname);
> - rc = -ENOENT;
> - goto out;
> - }
> -
> new_name = smb2_get_name(file_info->FileName,
> le32_to_cpu(file_info->FileNameLength),
> local_nls);
> - if (IS_ERR(new_name)) {
> - rc = PTR_ERR(new_name);
> - goto out;
> - }
> + if (IS_ERR(new_name))
> + return PTR_ERR(new_name);
>
> if (strchr(new_name, ':')) {
> int s_type;
> @@ -5425,7 +5400,7 @@ static int smb2_rename(struct ksmbd_work *work,
> if (rc)
> goto out;
>
> - rc = ksmbd_vfs_setxattr(user_ns,
> + rc = ksmbd_vfs_setxattr(file_mnt_user_ns(fp->filp),
> fp->filp->f_path.dentry,
> xattr_stream_name,
> NULL, 0, 0);
> @@ -5440,47 +5415,18 @@ static int smb2_rename(struct ksmbd_work *work,
> }
>
> ksmbd_debug(SMB, "new name %s\n", new_name);
> - rc = ksmbd_vfs_kern_path(work, new_name, LOOKUP_NO_SYMLINKS, &path, 1);
> - if (rc) {
> - if (rc != -ENOENT)
> - goto out;
> - file_present = false;
> - } else {
> - path_put(&path);
> - }
> -
> if (ksmbd_share_veto_filename(share, new_name)) {
> rc = -ENOENT;
> ksmbd_debug(SMB, "Can't rename vetoed file: %s\n", new_name);
> goto out;
> }
>
> - if (file_info->ReplaceIfExists) {
> - if (file_present) {
> - rc = ksmbd_vfs_remove_file(work, new_name);
> - if (rc) {
> - if (rc != -ENOTEMPTY)
> - rc = -EINVAL;
> - ksmbd_debug(SMB, "cannot delete %s, rc %d\n",
> - new_name, rc);
> - goto out;
> - }
> - }
> - } else {
> - if (file_present &&
> - strncmp(old_name, path.dentry->d_name.name, strlen(old_name))) {
> - rc = -EEXIST;
> - ksmbd_debug(SMB,
> - "cannot rename already existing file\n");
> - goto out;
> - }
> - }
> + if (!file_info->ReplaceIfExists)
> + flags = RENAME_NOREPLACE;
>
> - rc = ksmbd_vfs_fp_rename(work, fp, new_name);
> + rc = ksmbd_vfs_rename(work, &fp->filp->f_path, new_name, flags);
> out:
> - kfree(pathname);
> - if (!IS_ERR(new_name))
> - kfree(new_name);
> + kfree(new_name);
> return rc;
> }
>
> @@ -5728,12 +5674,6 @@ static int set_rename_info(struct ksmbd_work *work,
> struct ksmbd_file *fp,
> struct smb2_file_rename_info *rename_info,
> unsigned int buf_len)
> {
> - struct user_namespace *user_ns;
> - struct ksmbd_file *parent_fp;
> - struct dentry *parent;
> - struct dentry *dentry = fp->filp->f_path.dentry;
> - int ret;
> -
> if (!(fp->daccess & FILE_DELETE_LE)) {
> pr_err("no right to delete : 0x%x\n", fp->daccess);
> return -EACCES;
> @@ -5743,32 +5683,7 @@ static int set_rename_info(struct ksmbd_work *work,
> struct ksmbd_file *fp,
> le32_to_cpu(rename_info->FileNameLength))
> return -EINVAL;
>
> - user_ns = file_mnt_user_ns(fp->filp);
> - if (ksmbd_stream_fd(fp))
> - goto next;
> -
> - parent = dget_parent(dentry);
> - ret = ksmbd_vfs_lock_parent(user_ns, parent, dentry);
> - if (ret) {
> - dput(parent);
> - return ret;
> - }
> -
> - parent_fp = ksmbd_lookup_fd_inode(d_inode(parent));
> - inode_unlock(d_inode(parent));
> - dput(parent);
> -
> - if (parent_fp) {
> - if (parent_fp->daccess & FILE_DELETE_LE) {
> - pr_err("parent dir is opened with delete access\n");
> - ksmbd_fd_put(work, parent_fp);
> - return -ESHARE;
> - }
> - ksmbd_fd_put(work, parent_fp);
> - }
> -next:
> - return smb2_rename(work, fp, user_ns, rename_info,
> - work->sess->conn->local_nls);
> + return smb2_rename(work, fp, rename_info, work->sess->conn->local_nls);
> }
>
> static int set_file_disposition_info(struct ksmbd_file *fp,
> diff --git a/fs/ksmbd/vfs.c b/fs/ksmbd/vfs.c
> index f79dfcebe480..93d3625bf6d1 100644
> --- a/fs/ksmbd/vfs.c
> +++ b/fs/ksmbd/vfs.c
> @@ -17,6 +17,7 @@
> #include <linux/vmalloc.h>
> #include <linux/sched/xacct.h>
> #include <linux/crc32c.h>
> +#include <linux/namei.h>
>
> #include "glob.h"
> #include "oplock.h"
> @@ -34,19 +35,6 @@
> #include "mgmt/user_session.h"
> #include "mgmt/user_config.h"
>
> -static char *extract_last_component(char *path)
> -{
> - char *p = strrchr(path, '/');
> -
> - if (p && p[1] != '\0') {
> - *p = '\0';
> - p++;
> - } else {
> - p = NULL;
> - }
> - return p;
> -}
> -
> static void ksmbd_vfs_inherit_owner(struct ksmbd_work *work,
> struct inode *parent_inode,
> struct inode *inode)
> @@ -60,38 +48,20 @@ static void ksmbd_vfs_inherit_owner(struct ksmbd_work
> *work,
>
> /**
> * ksmbd_vfs_lock_parent() - lock parent dentry if it is stable
> - *
> - * the parent dentry got by dget_parent or @parent could be
> - * unstable, we try to lock a parent inode and lookup the
> - * child dentry again.
> - *
> - * the reference count of @parent isn't incremented.
> */
> -int ksmbd_vfs_lock_parent(struct user_namespace *user_ns, struct dentry
> *parent,
> - struct dentry *child)
> +struct dentry *ksmbd_vfs_lock_parent(struct dentry *child)
> {
> - struct dentry *dentry;
> - int ret = 0;
> + struct dentry *parent;
>
> + parent = dget(child->d_parent);
> inode_lock_nested(d_inode(parent), I_MUTEX_PARENT);
> - dentry = lookup_one(user_ns, child->d_name.name, parent,
> - child->d_name.len);
> - if (IS_ERR(dentry)) {
> - ret = PTR_ERR(dentry);
> - goto out_err;
> - }
> -
> - if (dentry != child) {
> - ret = -ESTALE;
> - dput(dentry);
> - goto out_err;
> + if (child->d_parent != parent) {
> + dput(parent);
> + inode_unlock(d_inode(parent));
> + return ERR_PTR(-EINVAL);
> }
>
> - dput(dentry);
> - return 0;
> -out_err:
> - inode_unlock(d_inode(parent));
> - return ret;
> + return parent;
> }
>
> int ksmbd_vfs_may_delete(struct user_namespace *user_ns,
> @@ -100,12 +70,9 @@ int ksmbd_vfs_may_delete(struct user_namespace
> *user_ns,
> struct dentry *parent;
> int ret;
>
> - parent = dget_parent(dentry);
> - ret = ksmbd_vfs_lock_parent(user_ns, parent, dentry);
> - if (ret) {
> - dput(parent);
> - return ret;
> - }
> + parent = ksmbd_vfs_lock_parent(dentry);
> + if (IS_ERR(parent))
> + return PTR_ERR(parent);
>
> ret = inode_permission(user_ns, d_inode(parent),
> MAY_EXEC | MAY_WRITE);
> @@ -135,12 +102,9 @@ int ksmbd_vfs_query_maximal_access(struct
> user_namespace *user_ns,
> if (!inode_permission(user_ns, d_inode(dentry), MAY_OPEN | MAY_EXEC))
> *daccess |= FILE_EXECUTE_LE;
>
> - parent = dget_parent(dentry);
> - ret = ksmbd_vfs_lock_parent(user_ns, parent, dentry);
> - if (ret) {
> - dput(parent);
> - return ret;
> - }
> + parent = ksmbd_vfs_lock_parent(dentry);
> + if (IS_ERR(parent))
> + return PTR_ERR(parent);
>
> if (!inode_permission(user_ns, d_inode(parent), MAY_EXEC | MAY_WRITE))
> *daccess |= FILE_DELETE_LE;
> @@ -599,14 +563,11 @@ int ksmbd_vfs_remove_file(struct ksmbd_work *work,
> char *name)
> return err;
> }
>
> - user_ns = mnt_user_ns(path.mnt);
> - parent = dget_parent(path.dentry);
> - err = ksmbd_vfs_lock_parent(user_ns, parent, path.dentry);
> - if (err) {
> - dput(parent);
> + parent = ksmbd_vfs_lock_parent(path.dentry);
> + if (IS_ERR(parent)) {
> path_put(&path);
> ksmbd_revert_fsids(work);
> - return err;
> + return PTR_ERR(parent);
> }
>
> if (!d_inode(path.dentry)->i_nlink) {
> @@ -614,6 +575,7 @@ int ksmbd_vfs_remove_file(struct ksmbd_work *work, char
> *name)
> goto out_err;
> }
>
> + user_ns = mnt_user_ns(path.mnt);
> if (S_ISDIR(d_inode(path.dentry)->i_mode)) {
> err = vfs_rmdir(user_ns, d_inode(parent), path.dentry);
> if (err && err != -ENOTEMPTY)
> @@ -688,149 +650,114 @@ int ksmbd_vfs_link(struct ksmbd_work *work, const
> char *oldname,
> return err;
> }
>
> -static int ksmbd_validate_entry_in_use(struct dentry *src_dent)
> +int ksmbd_vfs_rename(struct ksmbd_work *work, struct path *old_path,
> + char *newname, int flags)
> {
> - struct dentry *dst_dent;
> -
> - spin_lock(&src_dent->d_lock);
> - list_for_each_entry(dst_dent, &src_dent->d_subdirs, d_child) {
> - struct ksmbd_file *child_fp;
> + struct dentry *old_parent, *new_dentry, *trap;
> + struct dentry *old_child = old_path->dentry;
> + struct path new_path;
> + struct qstr new_last;
> + struct renamedata rd;
> + struct filename *to;
> + struct ksmbd_share_config *share_conf = work->tcon->share_conf;
> + struct ksmbd_file *parent_fp;
> + int new_type;
> + int err, lookup_flags = LOOKUP_NO_SYMLINKS;
>
> - if (d_really_is_negative(dst_dent))
> - continue;
> + if (ksmbd_override_fsids(work))
> + return -ENOMEM;
>
> - child_fp = ksmbd_lookup_fd_inode(d_inode(dst_dent));
> - if (child_fp) {
> - spin_unlock(&src_dent->d_lock);
> - ksmbd_debug(VFS, "Forbid rename, sub file/dir is in use\n");
> - return -EACCES;
> - }
> + to = getname_kernel(newname);
> + if (IS_ERR(to)) {
> + err = PTR_ERR(to);
> + goto revert_fsids;
> }
> - spin_unlock(&src_dent->d_lock);
>
> - return 0;
> -}
> +retry:
> + err = vfs_path_parent_lookup(to, lookup_flags | LOOKUP_BENEATH,
> + &new_path, &new_last, &new_type,
> + &share_conf->vfs_path);
> + if (err)
> + goto out1;
>
> -static int __ksmbd_vfs_rename(struct ksmbd_work *work,
> - struct user_namespace *src_user_ns,
> - struct dentry *src_dent_parent,
> - struct dentry *src_dent,
> - struct user_namespace *dst_user_ns,
> - struct dentry *dst_dent_parent,
> - struct dentry *trap_dent,
> - char *dst_name)
> -{
> - struct dentry *dst_dent;
> - int err;
> + if (old_path->mnt != new_path.mnt) {
> + err = -EXDEV;
> + goto out2;
> + }
>
> - if (!work->tcon->posix_extensions) {
> - err = ksmbd_validate_entry_in_use(src_dent);
> - if (err)
> - return err;
> + trap = lock_rename_child(old_child, new_path.dentry);
> +
> + old_parent = dget(old_child->d_parent);
> + if (d_unhashed(old_child)) {
> + err = -EINVAL;
> + goto out3;
> }
>
> - if (d_really_is_negative(src_dent_parent))
> - return -ENOENT;
> - if (d_really_is_negative(dst_dent_parent))
> - return -ENOENT;
> - if (d_really_is_negative(src_dent))
> - return -ENOENT;
> - if (src_dent == trap_dent)
> - return -EINVAL;
> + parent_fp = ksmbd_lookup_fd_inode(d_inode(old_child->d_parent));
> + if (parent_fp) {
> + if (parent_fp->daccess & FILE_DELETE_LE) {
> + pr_err("parent dir is opened with delete access\n");
> + err = -ESHARE;
> + ksmbd_fd_put(work, parent_fp);
> + goto out3;
> + }
> + ksmbd_fd_put(work, parent_fp);
> + }
>
> - if (ksmbd_override_fsids(work))
> - return -ENOMEM;
> + new_dentry = __lookup_hash(&new_last, new_path.dentry,
> + lookup_flags | LOOKUP_RENAME_TARGET);
> + if (IS_ERR(new_dentry)) {
> + err = PTR_ERR(new_dentry);
> + goto out3;
> + }
>
> - dst_dent = lookup_one(dst_user_ns, dst_name, dst_dent_parent,
> - strlen(dst_name));
> - err = PTR_ERR(dst_dent);
> - if (IS_ERR(dst_dent)) {
> - pr_err("lookup failed %s [%d]\n", dst_name, err);
> - goto out;
> + if (d_is_symlink(new_dentry)) {
> + err = -EACCES;
> + goto out4;
> }
>
> - err = -ENOTEMPTY;
> - if (dst_dent != trap_dent && !d_really_is_positive(dst_dent)) {
> - struct renamedata rd = {
> - .old_mnt_userns = src_user_ns,
> - .old_dir = d_inode(src_dent_parent),
> - .old_dentry = src_dent,
> - .new_mnt_userns = dst_user_ns,
> - .new_dir = d_inode(dst_dent_parent),
> - .new_dentry = dst_dent,
> - };
> - err = vfs_rename(&rd);
> + if ((flags & RENAME_NOREPLACE) && d_is_positive(new_dentry)) {
> + err = -EEXIST;
> + goto out4;
> }
> - if (err)
> - pr_err("vfs_rename failed err %d\n", err);
> - if (dst_dent)
> - dput(dst_dent);
> -out:
> - ksmbd_revert_fsids(work);
> - return err;
> -}
>
> -int ksmbd_vfs_fp_rename(struct ksmbd_work *work, struct ksmbd_file *fp,
> - char *newname)
> -{
> - struct user_namespace *user_ns;
> - struct path dst_path;
> - struct dentry *src_dent_parent, *dst_dent_parent;
> - struct dentry *src_dent, *trap_dent, *src_child;
> - char *dst_name;
> - int err;
> + if (old_child == trap) {
> + err = -EINVAL;
> + goto out4;
> + }
>
> - dst_name = extract_last_component(newname);
> - if (!dst_name) {
> - dst_name = newname;
> - newname = "";
> + if (new_dentry == trap) {
> + err = -ENOTEMPTY;
> + goto out4;
> }
>
> - src_dent_parent = dget_parent(fp->filp->f_path.dentry);
> - src_dent = fp->filp->f_path.dentry;
> + rd.old_mnt_userns = mnt_user_ns(old_path->mnt),
> + rd.old_dir = d_inode(old_parent),
> + rd.old_dentry = old_child,
> + rd.new_mnt_userns = mnt_user_ns(new_path.mnt),
> + rd.new_dir = new_path.dentry->d_inode,
> + rd.new_dentry = new_dentry,
> + rd.flags = flags,
> + err = vfs_rename(&rd);
> + if (err)
> + ksmbd_debug(VFS, "vfs_rename failed err %d\n", err);
>
> - err = ksmbd_vfs_kern_path(work, newname,
> - LOOKUP_NO_SYMLINKS | LOOKUP_DIRECTORY,
> - &dst_path, false);
> - if (err) {
> - ksmbd_debug(VFS, "Cannot get path for %s [%d]\n", newname, err);
> - goto out;
> +out4:
> + dput(new_dentry);
> +out3:
> + dput(old_parent);
> + unlock_rename(old_parent, new_path.dentry);
> +out2:
> + path_put(&new_path);
> +
> + if (retry_estale(err, lookup_flags)) {
> + lookup_flags |= LOOKUP_REVAL;
> + goto retry;
> }
> - dst_dent_parent = dst_path.dentry;
> -
> - trap_dent = lock_rename(src_dent_parent, dst_dent_parent);
> - dget(src_dent);
> - dget(dst_dent_parent);
> - user_ns = file_mnt_user_ns(fp->filp);
> - src_child = lookup_one(user_ns, src_dent->d_name.name, src_dent_parent,
> - src_dent->d_name.len);
> - if (IS_ERR(src_child)) {
> - err = PTR_ERR(src_child);
> - goto out_lock;
> - }
> -
> - if (src_child != src_dent) {
> - err = -ESTALE;
> - dput(src_child);
> - goto out_lock;
> - }
> - dput(src_child);
> -
> - err = __ksmbd_vfs_rename(work,
> - user_ns,
> - src_dent_parent,
> - src_dent,
> - mnt_user_ns(dst_path.mnt),
> - dst_dent_parent,
> - trap_dent,
> - dst_name);
> -out_lock:
> - dput(src_dent);
> - dput(dst_dent_parent);
> - unlock_rename(src_dent_parent, dst_dent_parent);
> - path_put(&dst_path);
> -out:
> - dput(src_dent_parent);
> +out1:
> + putname(to);
> +revert_fsids:
> + ksmbd_revert_fsids(work);
> return err;
> }
>
> @@ -1079,14 +1006,17 @@ int ksmbd_vfs_remove_xattr(struct user_namespace
> *user_ns,
> return vfs_removexattr(user_ns, dentry, attr_name);
> }
>
> -int ksmbd_vfs_unlink(struct user_namespace *user_ns,
> - struct dentry *dir, struct dentry *dentry)
> +int ksmbd_vfs_unlink(struct file *filp)
> {
> int err = 0;
> + struct dentry *dir, *dentry = filp->f_path.dentry;
> + struct user_namespace *user_ns = file_mnt_user_ns(filp);
>
> - err = ksmbd_vfs_lock_parent(user_ns, dir, dentry);
> - if (err)
> - return err;
> + dir = ksmbd_vfs_lock_parent(dentry);
> + if (IS_ERR(dir)) {
> + err = PTR_ERR(dir);
> + goto out;
> + }
> dget(dentry);
>
> if (S_ISDIR(d_inode(dentry)->i_mode))
> @@ -1098,6 +1028,8 @@ int ksmbd_vfs_unlink(struct user_namespace *user_ns,
> inode_unlock(d_inode(dir));
> if (err)
> ksmbd_debug(VFS, "failed to delete, err %d\n", err);
> +out:
> + dput(dir);
>
> return err;
> }
> diff --git a/fs/ksmbd/vfs.h b/fs/ksmbd/vfs.h
> index 8c37aaf936ab..f79e73b6f01b 100644
> --- a/fs/ksmbd/vfs.h
> +++ b/fs/ksmbd/vfs.h
> @@ -69,8 +69,7 @@ struct ksmbd_kstat {
> __le32 file_attributes;
> };
>
> -int ksmbd_vfs_lock_parent(struct user_namespace *user_ns, struct dentry
> *parent,
> - struct dentry *child);
> +struct dentry *ksmbd_vfs_lock_parent(struct dentry *child);
> int ksmbd_vfs_may_delete(struct user_namespace *user_ns, struct dentry
> *dentry);
> int ksmbd_vfs_query_maximal_access(struct user_namespace *user_ns,
> struct dentry *dentry, __le32 *daccess);
> @@ -86,8 +85,8 @@ int ksmbd_vfs_remove_file(struct ksmbd_work *work, char
> *name);
> int ksmbd_vfs_link(struct ksmbd_work *work,
> const char *oldname, const char *newname);
> int ksmbd_vfs_getattr(struct path *path, struct kstat *stat);
> -int ksmbd_vfs_fp_rename(struct ksmbd_work *work, struct ksmbd_file *fp,
> - char *newname);
> +int ksmbd_vfs_rename(struct ksmbd_work *work, struct path *old_path,
> + char *newname, int flags);
> int ksmbd_vfs_truncate(struct ksmbd_work *work,
> struct ksmbd_file *fp, loff_t size);
> struct srv_copychunk;
> @@ -129,8 +128,7 @@ struct file_allocated_range_buffer;
> int ksmbd_vfs_fqar_lseek(struct ksmbd_file *fp, loff_t start, loff_t
> length,
> struct file_allocated_range_buffer *ranges,
> unsigned int in_count, unsigned int *out_count);
> -int ksmbd_vfs_unlink(struct user_namespace *user_ns,
> - struct dentry *dir, struct dentry *dentry);
> +int ksmbd_vfs_unlink(struct file *filp);
> void *ksmbd_vfs_init_kstat(char **p, struct ksmbd_kstat *ksmbd_kstat);
> int ksmbd_vfs_fill_dentry_attrs(struct ksmbd_work *work,
> struct user_namespace *user_ns,
> diff --git a/fs/ksmbd/vfs_cache.c b/fs/ksmbd/vfs_cache.c
> index c4d59d2735f0..df600eb04552 100644
> --- a/fs/ksmbd/vfs_cache.c
> +++ b/fs/ksmbd/vfs_cache.c
> @@ -243,7 +243,6 @@ void ksmbd_release_inode_hash(void)
>
> static void __ksmbd_inode_close(struct ksmbd_file *fp)
> {
> - struct dentry *dir, *dentry;
> struct ksmbd_inode *ci = fp->f_ci;
> int err;
> struct file *filp;
> @@ -262,11 +261,9 @@ static void __ksmbd_inode_close(struct ksmbd_file *fp)
> if (atomic_dec_and_test(&ci->m_count)) {
> write_lock(&ci->m_lock);
> if (ci->m_flags & (S_DEL_ON_CLS | S_DEL_PENDING)) {
> - dentry = filp->f_path.dentry;
> - dir = dentry->d_parent;
> ci->m_flags &= ~(S_DEL_ON_CLS | S_DEL_PENDING);
> write_unlock(&ci->m_lock);
> - ksmbd_vfs_unlink(file_mnt_user_ns(filp), dir, dentry);
> + ksmbd_vfs_unlink(filp);
> write_lock(&ci->m_lock);
> }
> write_unlock(&ci->m_lock);
> diff --git a/fs/namei.c b/fs/namei.c
> index 516b8d147744..1c0de16f9cb9 100644
> --- a/fs/namei.c
> +++ b/fs/namei.c
> @@ -252,6 +252,7 @@ getname_kernel(const char * filename)
>
> return result;
> }
> +EXPORT_SYMBOL(getname_kernel);
>
> void putname(struct filename *name)
> {
> @@ -269,6 +270,7 @@ void putname(struct filename *name)
> } else
> __putname(name);
> }
> +EXPORT_SYMBOL(putname);
>
> /**
> * check_acl - perform ACL permission checking
> @@ -1587,8 +1589,8 @@ static struct dentry *lookup_dcache(const struct qstr
> *name,
> * when directory is guaranteed to have no in-lookup children
> * at all.
> */
> -static struct dentry *__lookup_hash(const struct qstr *name,
> - struct dentry *base, unsigned int flags)
> +struct dentry *__lookup_hash(const struct qstr *name, struct dentry *base,
> + unsigned int flags)
> {
> struct dentry *dentry = lookup_dcache(name, base, flags);
> struct dentry *old;
> @@ -1612,6 +1614,7 @@ static struct dentry *__lookup_hash(const struct qstr
> *name,
> }
> return dentry;
> }
> +EXPORT_SYMBOL(__lookup_hash);
>
> static struct dentry *lookup_fast(struct nameidata *nd,
> struct inode **inode,
> @@ -2556,16 +2559,17 @@ static int path_parentat(struct nameidata *nd,
> unsigned flags,
> }
>
> /* Note: this does not consume "name" */
> -static int filename_parentat(int dfd, struct filename *name,
> - unsigned int flags, struct path *parent,
> - struct qstr *last, int *type)
> +static int __filename_parentat(int dfd, struct filename *name,
> + unsigned int flags, struct path *parent,
> + struct qstr *last, int *type,
> + const struct path *root)
> {
> int retval;
> struct nameidata nd;
>
> if (IS_ERR(name))
> return PTR_ERR(name);
> - set_nameidata(&nd, dfd, name, NULL);
> + set_nameidata(&nd, dfd, name, root);
> retval = path_parentat(&nd, flags | LOOKUP_RCU, parent);
> if (unlikely(retval == -ECHILD))
> retval = path_parentat(&nd, flags, parent);
> @@ -2580,6 +2584,13 @@ static int filename_parentat(int dfd, struct filename
> *name,
> return retval;
> }
>
> +static int filename_parentat(int dfd, struct filename *name,
> + unsigned int flags, struct path *parent,
> + struct qstr *last, int *type)
> +{
> + return __filename_parentat(dfd, name, flags, parent, last, type, NULL);
> +}
> +
> /* does lookup, returns the object with parent locked */
> static struct dentry *__kern_path_locked(struct filename *name, struct path
> *path)
> {
> @@ -2623,6 +2634,24 @@ int kern_path(const char *name, unsigned int flags,
> struct path *path)
> }
> EXPORT_SYMBOL(kern_path);
>
> +/**
> + * vfs_path_parent_lookup - lookup a parent path relative to a
> dentry-vfsmount pair
> + * @filename: filename structure
> + * @flags: lookup flags
> + * @parent: pointer to struct path to fill
> + * @last: last component
> + * @type: type of the last component
> + * @root: pointer to struct path of the base directory
> + */
> +int vfs_path_parent_lookup(struct filename *filename, unsigned int flags,
> + struct path *parent, struct qstr *last, int *type,
> + const struct path *root)
> +{
> + return __filename_parentat(AT_FDCWD, filename, flags, parent, last,
> + type, root);
> +}
> +EXPORT_SYMBOL(vfs_path_parent_lookup);
> +
> /**
> * vfs_path_lookup - lookup a file path relative to a dentry-vfsmount pair
> * @dentry: pointer to dentry of the base directory
> diff --git a/include/linux/namei.h b/include/linux/namei.h
> index e6949d4ba188..f9be815f12b0 100644
> --- a/include/linux/namei.h
> +++ b/include/linux/namei.h
> @@ -57,12 +57,17 @@ static inline int user_path_at(int dfd, const char
> __user *name, unsigned flags,
> return user_path_at_empty(dfd, name, flags, path, NULL);
> }
>
> +struct dentry *__lookup_hash(const struct qstr *name, struct dentry *base,
> + unsigned int flags);
> extern int kern_path(const char *, unsigned, struct path *);
>
> extern struct dentry *kern_path_create(int, const char *, struct path *,
> unsigned int);
> extern struct dentry *user_path_create(int, const char __user *, struct
> path *, unsigned int);
> extern void done_path_create(struct path *, struct dentry *);
> extern struct dentry *kern_path_locked(const char *, struct path *);
> +int vfs_path_parent_lookup(struct filename *filename, unsigned int flags,
> + struct path *parent, struct qstr *last, int *type,
> + const struct path *root);
> int vfs_path_lookup(struct dentry *, struct vfsmount *, const char *,
> unsigned int, struct path *);
>
> --
> 2.25.1
>
>
