Re: [PATCH v2] nfsd: depend on CRYPTO_MD5 for legacy client tracking

From: "J. Bruce Fields" <bfields@fieldses.org>
To: Patrick Steinhardt <ps@pks.im>
Cc: linux-nfs@vger.kernel.org, Chuck Lever <chuck.lever@oracle.com>
Subject: Re: [PATCH v2] nfsd: depend on CRYPTO_MD5 for legacy client tracking
Date: Fri, 6 Dec 2019 16:03:00 -0500	[thread overview]
Message-ID: <20191206210300.GA17524@fieldses.org> (raw)
In-Reply-To: <7af3028bd374451f35e36a6c289c44d9c932ee71.1575439669.git.ps@pks.im>

Thanks, applied your v2.

--b.

On Wed, Dec 04, 2019 at 07:13:22AM +0100, Patrick Steinhardt wrote:
> The legacy client tracking infrastructure of nfsd makes use of MD5 to
> derive a client's recovery directory name. As the nfsd module doesn't
> declare any dependency on CRYPTO_MD5, though, it may fail to allocate
> the hash if the kernel was compiled without it. As a result, generation
> of client recovery directories will fail with the following error:
> 
>     NFSD: unable to generate recoverydir name
> 
> The explicit dependency on CRYPTO_MD5 was removed as redundant back in
> 6aaa67b5f3b9 (NFSD: Remove redundant "select" clauses in fs/Kconfig
> 2008-02-11) as it was already implicitly selected via RPCSEC_GSS_KRB5.
> This broke when RPCSEC_GSS_KRB5 was made optional for NFSv4 in commit
> df486a25900f (NFS: Fix the selection of security flavours in Kconfig) at
> a later point.
> 
> Fix the issue by adding back an explicit dependency on CRYPTO_MD5.
> 
> Fixes: df486a25900f (NFS: Fix the selection of security flavours in Kconfig)
> Signed-off-by: Patrick Steinhardt <ps@pks.im>
> ---
> 
> The only change compared to v1 is in the commit message. As
> pointed out by Chuck, it wasn't actually commit 6aaa67b5f3b9
> which broke it, but the later df486a25900f. I've reworded the
> commit message and fixed the Fixes tag to account for that.
> 
>  fs/nfsd/Kconfig | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/fs/nfsd/Kconfig b/fs/nfsd/Kconfig
> index c4b1a89b8845..f2f81561ebb6 100644
> --- a/fs/nfsd/Kconfig
> +++ b/fs/nfsd/Kconfig
> @@ -73,6 +73,7 @@ config NFSD_V4
>  	select NFSD_V3
>  	select FS_POSIX_ACL
>  	select SUNRPC_GSS
> +	select CRYPTO_MD5
>  	select CRYPTO_SHA256
>  	select GRACE_PERIOD
>  	help
> -- 
> 2.24.0