linux-kernel - Re: [PATCH v3] xfs: Replace strncpy with memcpy

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] [day] [month] [year] [list]

Message-ID: <20250828145400.GH8096@frogsfrogsfrogs>
Date: Thu, 28 Aug 2025 07:54:00 -0700
From: "Darrick J. Wong" <djwong@...nel.org>
To: Marcelo Moreira <marcelomoreira1905@...il.com>
Cc: cem@...nel.org, linux-xfs@...r.kernel.org, linux-kernel@...r.kernel.org,
	skhan@...uxfoundation.org,
	linux-kernel-mentees@...ts.linuxfoundation.org
Subject: Re: [PATCH v3] xfs: Replace strncpy with memcpy

On Wed, Aug 27, 2025 at 07:17:07PM -0300, Marcelo Moreira wrote:
> The changes modernizes the code by aligning it with current kernel best
> practices. It improves code clarity and consistency, as strncpy is deprecated
> as explained in Documentation/process/deprecated.rst. This change does
> not alter the functionality or introduce any behavioral changes.
> 
> Suggested-by: Dave Chinner <david@...morbit.com>
> Reviewed-by: Christoph Hellwig <hch@....de>
> Reviewed-by: Carlos Maiolino <cmaiolino@...hat.com>
> Signed-off-by: Marcelo Moreira <marcelomoreira1905@...il.com>

memcpy is fine, the repair code determines the new target length via
strnlen(bufsize) later on so we'll continue to fix the "non-null
characters after the zero terminator" case.

Reviewed-by: "Darrick J. Wong" <djwong@...nel.org>

--D

> ---
> Changes since v2:
> - Fixing some errors in the commit message.
> Link to v2: https://lore.kernel.org/linux-kernel-mentees/CAPZ3m_iNj2zwpAovv3BTz8gNp5XzdxSRHBFonM9sJvaSjYVBeg@mail.gmail.com/T/#t
> 
>  fs/xfs/scrub/symlink_repair.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/xfs/scrub/symlink_repair.c b/fs/xfs/scrub/symlink_repair.c
> index 953ce7be78dc..5902398185a8 100644
> --- a/fs/xfs/scrub/symlink_repair.c
> +++ b/fs/xfs/scrub/symlink_repair.c
> @@ -185,7 +185,7 @@ xrep_symlink_salvage_inline(
>  		return 0;
>  
>  	nr = min(XFS_SYMLINK_MAXLEN, xfs_inode_data_fork_size(ip));
> -	strncpy(target_buf, ifp->if_data, nr);
> +	memcpy(target_buf, ifp->if_data, nr);
>  	return nr;
>  }
>  
> -- 
> 2.50.1
> 
>