From patchwork Sun Apr 14 17:01:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Kaiser X-Patchwork-Id: 13629161 Received: from akranes.kaiser.cx (akranes.kaiser.cx [152.53.16.207]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7B8C3134CE8; Sun, 14 Apr 2024 17:11:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=152.53.16.207 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713114674; cv=none; b=YjJqb5NIIjeYv5E4HrsXMb9W5pQQ/q3qMu7MYDTGNiBANaOZ6UO92PCmv85+U9oy+GeWR0EyxzMy0u7meRkPDqK3Z2ZjhzhRj3MoHofNJ5gG2YTMTOviVQ2ScQQLOWEmGusuccpbAHRpYw2mVKKK3OJeO7A+D/dB6CP+pkJSF3I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713114674; c=relaxed/simple; bh=wpe8KlwzaSSM+u2lvF16DyF5qHpDrPDvVSCVM3ngkNQ=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=qqpCE7G9sxwBQup+0lZ6y3tCXvJ2helv3Ju61c4cJLFXwhXq4gIeKZWImGtNuSTvIZ5ofeewkT8SUjLmzyTVetd5WvnVBKUiHvSeUS64z+cD773Fiq5qjpa7S91XpAj95zfn32OK1vYe/RaRis0EEYlzoaOzWt9eBArvvWzBOQg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kaiser.cx; spf=pass smtp.mailfrom=kaiser.cx; arc=none smtp.client-ip=152.53.16.207 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kaiser.cx Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kaiser.cx Received: from dslb-188-097-210-242.188.097.pools.vodafone-ip.de ([188.97.210.242] helo=martin-debian-3.kaiser.cx) by akranes.kaiser.cx with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1rw3Dj-003uVz-0Q; Sun, 14 Apr 2024 19:00:47 +0200 From: Martin Kaiser To: Anna Schumaker , Trond Myklebust , David Howells Cc: NeilBrown , Jeff Layton , Josef Bacik , Chuck Lever , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Martin Kaiser Subject: [PATCH v3] nfs: keep server info for remounts Date: Sun, 14 Apr 2024 19:01:09 +0200 Message-Id: <20240414170109.137696-1-martin@kaiser.cx> X-Mailer: git-send-email 2.39.2 Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 With newer kernels that use fs_context for nfs mounts, remounts fail with -EINVAL. $ mount -t nfs -o nolock 10.0.0.1:/tmp/test /mnt/test/ $ mount -t nfs -o remount /mnt/test/ mount: mounting 10.0.0.1:/tmp/test on /mnt/test failed: Invalid argument For remounts, the nfs server address and port are populated by nfs_init_fs_context and later overwritten with 0x00 bytes by nfs23_parse_monolithic. The remount then fails as the server address is invalid. Fix this by not overwriting nfs server info in nfs23_parse_monolithic if we're doing a remount. Fixes: f2aedb713c28 ("NFS: Add fs_context support.") Signed-off-by: Martin Kaiser --- v3: - rebased against linux-next from 12th April 2024 v2: - rebased against linux-next from 26th February 2024 Dear all, I'm resending this patch again. The problem that I'm trying to fix is still present in linux-next. Thanks in advance for any reviews and comments. I guess that we're taking this path for remounts do_remount fs_context_for_reconfigure alloc_fs_context init_fs_context == nfs_init_fs_context fc->root is set for remounts ctx->nfs_server is populated parse_monolithic_mount_data nfs_fs_context_parse_monolithic nfs23_parse_monolithic ctx->nfs_server is overwritten with data from mount request An alternative to checking for !is_remount_fc(fc) would be to check if (ctx->nfs_server.addrlen == 0) fs/nfs/fs_context.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c index d0a0956f8a13..cac1157be2c2 100644 --- a/fs/nfs/fs_context.c +++ b/fs/nfs/fs_context.c @@ -1112,9 +1112,12 @@ static int nfs23_parse_monolithic(struct fs_context *fc, ctx->acdirmax = data->acdirmax; ctx->need_mount = false; - memcpy(sap, &data->addr, sizeof(data->addr)); - ctx->nfs_server.addrlen = sizeof(data->addr); - ctx->nfs_server.port = ntohs(data->addr.sin_port); + if (!is_remount_fc(fc)) { + memcpy(sap, &data->addr, sizeof(data->addr)); + ctx->nfs_server.addrlen = sizeof(data->addr); + ctx->nfs_server.port = ntohs(data->addr.sin_port); + } + if (sap->ss_family != AF_INET || !nfs_verify_server_address(sap)) goto out_no_address;