Commit ef85e43f authored by Al Viro's avatar Al Viro Committed by Wen Zhiwei
Browse files

udf_rename(): only access the child content on cross-directory rename 

stable inclusion
from stable-v6.6.70
commit 17b312c5d86909bd53da5a49cd4589a17f97c439
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IBOHV1

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=17b312c5d86909bd53da5a49cd4589a17f97c439



--------------------------------

[ Upstream commit 9d35cebb794bb7be93db76c3383979c7deacfef9 ]

We can't really afford locking the source on same-directory rename;
currently vfs_rename() tries to do that, but it will have to be
changed.  The logics in udf_rename() is lazy and goes looking for
".." in source even in same-directory case.  It's not hard to get
rid of that, leaving that behaviour only for cross-directory case;
that VFS can get locks safely (and will keep doing that after the
coming changes).

Reviewed-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Stable-dep-of: 6756af923e06 ("udf: Verify inode link counts before performing rename")
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarWen Zhiwei <wenzhiwei@kylinos.cn>
parent 36e09793

fs/udf/namei.c

+6 −1
Original line number Diff line number Diff line
@@ -770,7 +770,7 @@ static int udf_rename(struct mnt_idmap *idmap, struct inode *old_dir, 
	struct inode *old_inode = d_inode(old_dentry);

	struct inode *new_inode = d_inode(new_dentry);

	struct udf_fileident_iter oiter, niter, diriter;

	bool has_diriter = false;

	bool has_diriter = false, is_dir = false;

	int retval;

	struct kernel_lb_addr tloc;
@@ -793,6 +793,9 @@ static int udf_rename(struct mnt_idmap *idmap, struct inode *old_dir, 
			if (!empty_dir(new_inode))

				goto out_oiter;

		}

		is_dir = true;

	}

	if (is_dir && old_dir != new_dir) {

		retval = udf_fiiter_find_entry(old_inode, &dotdot_name,

					       &diriter);

		if (retval == -ENOENT) {
@@ -880,7 +883,9 @@ static int udf_rename(struct mnt_idmap *idmap, struct inode *old_dir, 
					cpu_to_lelb(UDF_I(new_dir)->i_location);

		udf_fiiter_write_fi(&diriter, NULL);

		udf_fiiter_release(&diriter);

	}



	if (is_dir) {

		inode_dec_link_count(old_dir);

		if (new_inode)

			inode_dec_link_count(new_inode);