From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4587BC433EF for ; Tue, 18 Jan 2022 08:06:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343818AbiARIG5 (ORCPT ); Tue, 18 Jan 2022 03:06:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52734 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343799AbiARIG5 (ORCPT ); Tue, 18 Jan 2022 03:06:57 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 321FEC061574 for ; Tue, 18 Jan 2022 00:06:57 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id E6559B81052 for ; Tue, 18 Jan 2022 08:06:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 28676C00446; Tue, 18 Jan 2022 08:06:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1642493214; bh=0FnDFVr8mEi2NDHDhMGOuiSigg6y0gPaK6HHacuiGQU=; h=Subject:To:Cc:From:Date:From; b=fz9OsXSm56wj8pA61Iz4k6FRJc+8ZzV6KIa09Z7PDKlNQhrgJQp97ogPe9BKM3ko5 8duaLKhPYLX8l3G1fYcAJ7aXRFU3Xo0eaxP1FDy6nTrXStezMterCtxM9McHipNLTS uf5ui+jBlCVVP92LAIwL6ET71FqldUw3GER1cR8I= Subject: FAILED: patch "[PATCH] NFSD: Fix zero-length NFSv3 WRITEs" failed to apply to 5.4-stable tree To: chuck.lever@oracle.com, trond.myklebust@hammerspace.com Cc: From: Date: Tue, 18 Jan 2022 09:06:43 +0100 Message-ID: <1642493203139123@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 6a2f774424bfdcc2df3e17de0cefe74a4269cad5 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Tue, 21 Dec 2021 11:52:06 -0500 Subject: [PATCH] NFSD: Fix zero-length NFSv3 WRITEs The Linux NFS server currently responds to a zero-length NFSv3 WRITE request with NFS3ERR_IO. It responds to a zero-length NFSv4 WRITE with NFS4_OK and count of zero. RFC 1813 says of the WRITE procedure's @count argument: count The number of bytes of data to be written. If count is 0, the WRITE will succeed and return a count of 0, barring errors due to permissions checking. RFC 8881 has similar language for NFSv4, though NFSv4 removed the explicit @count argument because that value is already contained in the opaque payload array. The synthetic client pynfs's WRT4 and WRT15 tests do emit zero- length WRITEs to exercise this spec requirement. Commit fdec6114ee1f ("nfsd4: zero-length WRITE should succeed") addressed the same problem there with the same fix. But interestingly the Linux NFS client does not appear to emit zero- length WRITEs, instead squelching them. I'm not aware of a test that can generate such WRITEs for NFSv3, so I wrote a naive C program to generate a zero-length WRITE and test this fix. Fixes: 8154ef2776aa ("NFSD: Clean up legacy NFS WRITE argument XDR decoders") Reported-by: Trond Myklebust Signed-off-by: Chuck Lever Cc: stable@vger.kernel.org Signed-off-by: Chuck Lever diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c index 4418517f6f12..2c681785186f 100644 --- a/fs/nfsd/nfs3proc.c +++ b/fs/nfsd/nfs3proc.c @@ -202,15 +202,11 @@ nfsd3_proc_write(struct svc_rqst *rqstp) fh_copy(&resp->fh, &argp->fh); resp->committed = argp->stable; nvecs = svc_fill_write_vector(rqstp, &argp->payload); - if (!nvecs) { - resp->status = nfserr_io; - goto out; - } + resp->status = nfsd_write(rqstp, &resp->fh, argp->offset, rqstp->rq_vec, nvecs, &cnt, resp->committed, resp->verf); resp->count = cnt; -out: return rpc_success; } diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c index eea5b59b6a6c..1743ed04197e 100644 --- a/fs/nfsd/nfsproc.c +++ b/fs/nfsd/nfsproc.c @@ -235,10 +235,6 @@ nfsd_proc_write(struct svc_rqst *rqstp) argp->len, argp->offset); nvecs = svc_fill_write_vector(rqstp, &argp->payload); - if (!nvecs) { - resp->status = nfserr_io; - goto out; - } resp->status = nfsd_write(rqstp, fh_copy(&resp->fh, &argp->fh), argp->offset, rqstp->rq_vec, nvecs, @@ -247,7 +243,6 @@ nfsd_proc_write(struct svc_rqst *rqstp) resp->status = fh_getattr(&resp->fh, &resp->stat); else if (resp->status == nfserr_jukebox) return rpc_drop_reply; -out: return rpc_success; }