linux-kernel - Re: [PATCH v2 07/11] xfs: switch to multigrain timestamps

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: <20240701134653.GA504479@perftesting>
Date: Mon, 1 Jul 2024 09:46:53 -0400
From: Josef Bacik <josef@...icpanda.com>
To: Jeff Layton <jlayton@...nel.org>
Cc: Alexander Viro <viro@...iv.linux.org.uk>,
	Christian Brauner <brauner@...nel.org>, Jan Kara <jack@...e.cz>,
	Steven Rostedt <rostedt@...dmis.org>,
	Masami Hiramatsu <mhiramat@...nel.org>,
	Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
	Chandan Babu R <chandan.babu@...cle.com>,
	"Darrick J. Wong" <djwong@...nel.org>,
	Theodore Ts'o <tytso@....edu>,
	Andreas Dilger <adilger.kernel@...ger.ca>, Chris Mason <clm@...com>,
	David Sterba <dsterba@...e.com>, Hugh Dickins <hughd@...gle.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Andi Kleen <ak@...ux.intel.com>, kernel-team@...com,
	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-trace-kernel@...r.kernel.org, linux-xfs@...r.kernel.org,
	linux-ext4@...r.kernel.org, linux-btrfs@...r.kernel.org,
	linux-mm@...ck.org, linux-nfs@...r.kernel.org
Subject: Re: [PATCH v2 07/11] xfs: switch to multigrain timestamps

On Mon, Jul 01, 2024 at 06:26:43AM -0400, Jeff Layton wrote:
> Enable multigrain timestamps, which should ensure that there is an
> apparent change to the timestamp whenever it has been written after
> being actively observed via getattr.
> 
> Also, anytime the mtime changes, the ctime must also change, and those
> are now the only two options for xfs_trans_ichgtime. Have that function
> unconditionally bump the ctime, and ASSERT that XFS_ICHGTIME_CHG is
> always set.
> 
> Signed-off-by: Jeff Layton <jlayton@...nel.org>
> ---
>  fs/xfs/libxfs/xfs_trans_inode.c | 6 +++---
>  fs/xfs/xfs_iops.c               | 6 ++++--
>  fs/xfs/xfs_super.c              | 2 +-
>  3 files changed, 8 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/xfs/libxfs/xfs_trans_inode.c b/fs/xfs/libxfs/xfs_trans_inode.c
> index 69fc5b981352..1f3639bbf5f0 100644
> --- a/fs/xfs/libxfs/xfs_trans_inode.c
> +++ b/fs/xfs/libxfs/xfs_trans_inode.c
> @@ -62,12 +62,12 @@ xfs_trans_ichgtime(
>  	ASSERT(tp);
>  	xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
>  
> -	tv = current_time(inode);
> +	/* If the mtime changes, then ctime must also change */
> +	ASSERT(flags & XFS_ICHGTIME_CHG);
>  
> +	tv = inode_set_ctime_current(inode);
>  	if (flags & XFS_ICHGTIME_MOD)
>  		inode_set_mtime_to_ts(inode, tv);
> -	if (flags & XFS_ICHGTIME_CHG)
> -		inode_set_ctime_to_ts(inode, tv);
>  	if (flags & XFS_ICHGTIME_CREATE)
>  		ip->i_crtime = tv;
>  }
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index ff222827e550..ed6e6d9507df 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -590,10 +590,12 @@ xfs_vn_getattr(
>  	stat->gid = vfsgid_into_kgid(vfsgid);
>  	stat->ino = ip->i_ino;
>  	stat->atime = inode_get_atime(inode);
> -	stat->mtime = inode_get_mtime(inode);
> -	stat->ctime = inode_get_ctime(inode);
> +
> +	fill_mg_cmtime(stat, request_mask, inode);
> +
>  	stat->blocks = XFS_FSB_TO_BB(mp, ip->i_nblocks + ip->i_delayed_blks);
>  
> +

Stray newline.  Thanks,

Josef