linux-kernel - [PATCH RFC v2 03/28] vfs: add try_break_deleg calls for parents to vfs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250602-dir-deleg-v2-3-a7919700de86@kernel.org>
Date: Mon, 02 Jun 2025 10:01:46 -0400
From: Jeff Layton <jlayton@...nel.org>
To: Alexander Viro <viro@...iv.linux.org.uk>, 
 Christian Brauner <brauner@...nel.org>, Jan Kara <jack@...e.cz>, 
 Chuck Lever <chuck.lever@...cle.com>, 
 Alexander Aring <alex.aring@...il.com>, 
 Trond Myklebust <trondmy@...nel.org>, Anna Schumaker <anna@...nel.org>, 
 Steve French <sfrench@...ba.org>, Paulo Alcantara <pc@...guebit.com>, 
 Ronnie Sahlberg <ronniesahlberg@...il.com>, 
 Shyam Prasad N <sprasad@...rosoft.com>, Tom Talpey <tom@...pey.com>, 
 Bharath SM <bharathsm@...rosoft.com>, NeilBrown <neil@...wn.name>, 
 Olga Kornievskaia <okorniev@...hat.com>, Dai Ngo <Dai.Ngo@...cle.com>, 
 Jonathan Corbet <corbet@....net>, Amir Goldstein <amir73il@...il.com>, 
 Miklos Szeredi <miklos@...redi.hu>
Cc: linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org, 
 linux-nfs@...r.kernel.org, linux-cifs@...r.kernel.org, 
 samba-technical@...ts.samba.org, linux-doc@...r.kernel.org, 
 Jeff Layton <jlayton@...nel.org>
Subject: [PATCH RFC v2 03/28] vfs: add try_break_deleg calls for parents to
 vfs_{link,rename,unlink}

In order to add directory delegation support, we need to break
delegations on the parent whenever there is going to be a change in the
directory.

vfs_link, vfs_unlink, and vfs_rename all have existing delegation break
handling for the children in the rename. Add the necessary calls for
breaking delegations in the parent(s) as well.

Signed-off-by: Jeff Layton <jlayton@...nel.org>
---
 fs/namei.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/fs/namei.c b/fs/namei.c
index 4bb889fc980b7d44914e11ec38ae3e8fdfbafadd..0fea12860036162c01a291558e068fde9c986142 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -4580,6 +4580,9 @@ int vfs_unlink(struct mnt_idmap *idmap, struct inode *dir,
 	else {
 		error = security_inode_unlink(dir, dentry);
 		if (!error) {
+			error = try_break_deleg(dir, delegated_inode);
+			if (error)
+				goto out;
 			error = try_break_deleg(target, delegated_inode);
 			if (error)
 				goto out;
@@ -4849,7 +4852,9 @@ int vfs_link(struct dentry *old_dentry, struct mnt_idmap *idmap,
 	else if (max_links && inode->i_nlink >= max_links)
 		error = -EMLINK;
 	else {
-		error = try_break_deleg(inode, delegated_inode);
+		error = try_break_deleg(dir, delegated_inode);
+		if (!error)
+			error = try_break_deleg(inode, delegated_inode);
 		if (!error)
 			error = dir->i_op->link(old_dentry, dir, new_dentry);
 	}
@@ -5115,6 +5120,14 @@ int vfs_rename(struct renamedata *rd)
 		    old_dir->i_nlink >= max_links)
 			goto out;
 	}
+	error = try_break_deleg(old_dir, delegated_inode);
+	if (error)
+		goto out;
+	if (new_dir != old_dir) {
+		error = try_break_deleg(new_dir, delegated_inode);
+		if (error)
+			goto out;
+	}
 	if (!is_dir) {
 		error = try_break_deleg(source, delegated_inode);
 		if (error)

-- 
2.49.0