linux-kernel - Re: [PATCH 4/5] exportfs: use lookup_one

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: <e5c5fdbf-1e4c-4fa9-93db-e23b04e0452c@oracle.com>
Date: Mon, 9 Jun 2025 10:01:26 -0400
From: Chuck Lever <chuck.lever@...cle.com>
To: NeilBrown <neil@...wn.name>, Alexander Viro <viro@...iv.linux.org.uk>,
        Christian Brauner <brauner@...nel.org>, Jan Kara <jack@...e.cz>,
        Jeff Layton <jlayton@...nel.org>, Amir Goldstein <amir73il@...il.com>,
        Jan Harkes <jaharkes@...cmu.edu>, David Howells <dhowells@...hat.com>,
        Tyler Hicks <code@...icks.com>, Miklos Szeredi <miklos@...redi.hu>,
        Carlos Maiolino <cem@...nel.org>
Cc: linux-fsdevel@...r.kernel.org, coda@...cmu.edu, codalist@...a.cs.cmu.edu,
        linux-nfs@...r.kernel.org, netfs@...ts.linux.dev,
        ecryptfs@...r.kernel.org, linux-unionfs@...r.kernel.org,
        linux-xfs@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 4/5] exportfs: use lookup_one_unlocked()

On 6/8/25 7:09 PM, NeilBrown wrote:
> rather than locking the directory and using lookup_one(), just use
> lookup_one_unlocked().  This keeps locking code centralised.
> 
> Signed-off-by: NeilBrown <neil@...wn.name>
> ---
>  fs/exportfs/expfs.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c
> index cdefea17986a..d3e55de4a2a2 100644
> --- a/fs/exportfs/expfs.c
> +++ b/fs/exportfs/expfs.c
> @@ -549,15 +549,13 @@ exportfs_decode_fh_raw(struct vfsmount *mnt, struct fid *fid, int fh_len,
>  			goto err_result;
>  		}
>  
> -		inode_lock(target_dir->d_inode);
> -		nresult = lookup_one(mnt_idmap(mnt), &QSTR(nbuf), target_dir);
> +		nresult = lookup_one_unlocked(mnt_idmap(mnt), &QSTR(nbuf), target_dir);
>  		if (!IS_ERR(nresult)) {
>  			if (unlikely(nresult->d_inode != result->d_inode)) {
>  				dput(nresult);
>  				nresult = ERR_PTR(-ESTALE);
>  			}
>  		}
> -		inode_unlock(target_dir->d_inode);
>  		/*
>  		 * At this point we are done with the parent, but it's pinned
>  		 * by the child dentry anyway.

Reviewed-by: Chuck Lever <chuck.lever@...cle.com>

-- 
Chuck Lever