namei: shift nameidata down into filename_parentat() (391172c4) · Commits · e / devices / android_kernel_fairphone_FP4

fs/namei.c

+43 −41

Original line number	Diff line number	Diff line
		@@ -2146,7 +2146,8 @@ static int filename_lookup(int dfd, struct filename *name, unsigned flags,

		/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
		static int path_parentat(int dfd, const struct filename *name,
		unsigned int flags, struct nameidata *nd)
		unsigned int flags, struct nameidata *nd,
		struct path *parent)
		{
		const char *s = path_init(dfd, name, flags, nd);
		int err;
		@@ -2155,26 +2156,34 @@ static int path_parentat(int dfd, const struct filename *name,
		err = link_path_walk(s, nd);
		if (!err)
		err = complete_walk(nd);
		if (err)
		if (!err) {
		*parent = nd->path;
		nd->path.mnt = NULL;
		nd->path.dentry = NULL;
		}
		terminate_walk(nd);
		path_cleanup(nd);
		return err;
		}

		static int filename_parentat(int dfd, struct filename *name,
		unsigned int flags, struct nameidata *nd)
		unsigned int flags, struct path *parent,
		struct qstr last, int type)
		{
		int retval;
		struct nameidata *saved_nd = set_nameidata(nd);
		struct nameidata nd, *saved_nd = set_nameidata(&nd);

		retval = path_parentat(dfd, name, flags \| LOOKUP_RCU, nd);
		retval = path_parentat(dfd, name, flags \| LOOKUP_RCU, &nd, parent);
		if (unlikely(retval == -ECHILD))
		retval = path_parentat(dfd, name, flags, nd);
		retval = path_parentat(dfd, name, flags, &nd, parent);
		if (unlikely(retval == -ESTALE))
		retval = path_parentat(dfd, name, flags \| LOOKUP_REVAL, nd);

		if (likely(!retval))
		audit_inode(name, nd->path.dentry, LOOKUP_PARENT);
		retval = path_parentat(dfd, name, flags \| LOOKUP_REVAL,
		&nd, parent);
		if (likely(!retval)) {
		*last = nd.last;
		*type = nd.last_type;
		audit_inode(name, parent->dentry, LOOKUP_PARENT);
		}
		restore_nameidata(saved_nd);
		return retval;
		}
		@@ -2183,31 +2192,30 @@ static int filename_parentat(int dfd, struct filename *name,
		struct dentry kern_path_locked(const char name, struct path *path)
		{
		struct filename *filename = getname_kernel(name);
		struct nameidata nd;
		struct qstr last;
		int type;
		struct dentry *d;
		int err;

		if (IS_ERR(filename))
		return ERR_CAST(filename);

		err = filename_parentat(AT_FDCWD, filename, 0, &nd);
		err = filename_parentat(AT_FDCWD, filename, 0, path, &last, &type);
		if (err) {
		d = ERR_PTR(err);
		goto out;
		}
		if (nd.last_type != LAST_NORM) {
		path_put(&nd.path);
		if (type != LAST_NORM) {
		path_put(path);
		d = ERR_PTR(-EINVAL);
		goto out;
		}
		mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
		d = __lookup_hash(&nd.last, nd.path.dentry, 0);
		mutex_lock_nested(&path->dentry->d_inode->i_mutex, I_MUTEX_PARENT);
		d = __lookup_hash(&last, path->dentry, 0);
		if (IS_ERR(d)) {
		mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
		path_put(&nd.path);
		goto out;
		mutex_unlock(&path->dentry->d_inode->i_mutex);
		path_put(path);
		}
		*path = nd.path;
		out:
		putname(filename);
		return d;
		@@ -2317,7 +2325,6 @@ user_path_parent(int dfd, const char __user *path,
		int *type,
		unsigned int flags)
		{
		struct nameidata nd;
		struct filename *s = getname(path);
		int error;

		@@ -2327,15 +2334,11 @@ user_path_parent(int dfd, const char __user *path,
		if (IS_ERR(s))
		return s;

		error = filename_parentat(dfd, s, flags, &nd);
		error = filename_parentat(dfd, s, flags, parent, last, type);
		if (error) {
		putname(s);
		return ERR_PTR(error);
		s = ERR_PTR(error);
		}
		*parent = nd.path;
		*last = nd.last;
		*type = nd.last_type;

		return s;
		}

		@@ -3394,7 +3397,8 @@ static struct dentry filename_create(int dfd, struct filename name,
		struct path *path, unsigned int lookup_flags)
		{
		struct dentry *dentry = ERR_PTR(-EEXIST);
		struct nameidata nd;
		struct qstr last;
		int type;
		int err2;
		int error;
		bool is_dir = (lookup_flags & LOOKUP_DIRECTORY);
		@@ -3405,7 +3409,7 @@ static struct dentry filename_create(int dfd, struct filename name,
		*/
		lookup_flags &= LOOKUP_REVAL;

		error = filename_parentat(dfd, name, lookup_flags, &nd);
		error = filename_parentat(dfd, name, lookup_flags, path, &last, &type);
		if (error)
		return ERR_PTR(error);

		@@ -3413,18 +3417,17 @@ static struct dentry filename_create(int dfd, struct filename name,
		* Yucky last component or no last component at all?
		* (foo/., foo/.., /////)
		*/
		if (nd.last_type != LAST_NORM)
		if (type != LAST_NORM)
		goto out;
		nd.flags &= ~LOOKUP_PARENT;
		nd.flags \|= LOOKUP_CREATE \| LOOKUP_EXCL;

		/* don't fail immediately if it's r/o, at least try to report other errors */
		err2 = mnt_want_write(nd.path.mnt);
		err2 = mnt_want_write(path->mnt);
		/*
		* Do the final lookup.
		*/
		mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
		dentry = __lookup_hash(&nd.last, nd.path.dentry, nd.flags);
		lookup_flags \|= LOOKUP_CREATE \| LOOKUP_EXCL;
		mutex_lock_nested(&path->dentry->d_inode->i_mutex, I_MUTEX_PARENT);
		dentry = __lookup_hash(&last, path->dentry, lookup_flags);
		if (IS_ERR(dentry))
		goto unlock;

		@@ -3438,7 +3441,7 @@ static struct dentry filename_create(int dfd, struct filename name,
		* all is fine. Let's be bastards - you had / on the end, you've
		* been asking for (non-existent) directory. -ENOENT for you.
		*/
		if (unlikely(!is_dir && nd.last.name[nd.last.len])) {
		if (unlikely(!is_dir && last.name[last.len])) {
		error = -ENOENT;
		goto fail;
		}
		@@ -3446,17 +3449,16 @@ static struct dentry filename_create(int dfd, struct filename name,
		error = err2;
		goto fail;
		}
		*path = nd.path;
		return dentry;
		fail:
		dput(dentry);
		dentry = ERR_PTR(error);
		unlock:
		mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
		mutex_unlock(&path->dentry->d_inode->i_mutex);
		if (!err2)
		mnt_drop_write(nd.path.mnt);
		mnt_drop_write(path->mnt);
		out:
		path_put(&nd.path);
		path_put(path);
		return dentry;
		}