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 X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E27BC11F64 for ; Thu, 1 Jul 2021 14:26:57 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E352A61409 for ; Thu, 1 Jul 2021 14:26:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E352A61409 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:50562 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lyxea-0008If-4a for qemu-devel@archiver.kernel.org; Thu, 01 Jul 2021 10:26:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34488) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lyxVF-0006Zw-S8 for qemu-devel@nongnu.org; Thu, 01 Jul 2021 10:17:17 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:36672) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lyxVD-0006Sk-B9 for qemu-devel@nongnu.org; Thu, 01 Jul 2021 10:17:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1625149034; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EHIZaWrzTWVadqEEpcR1o8cVL1MoQyDMpjctO98rEi8=; b=Ys66y9y16Zrf+evdAJlgrbiT35KbTbCB8LswidvYtpP77zqIgbDGsi3Jjfd+I5h0G62Y3q jajPeaKOzLHy+n7XuVg5s3rGg/3CFsf/9Zx696qZ+Pi4p7qf+uurCtuK4HlgQWwQrTt8ZO 4Am1LZpmJUh/K6NENnnVFlozd1x+ddo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-37-av0ZmUqMMHecU3GAXKs_XA-1; Thu, 01 Jul 2021 10:17:11 -0400 X-MC-Unique: av0ZmUqMMHecU3GAXKs_XA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0FAF2804142; Thu, 1 Jul 2021 14:17:09 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-114-230.ams2.redhat.com [10.36.114.230]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8983860843; Thu, 1 Jul 2021 14:16:56 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, berrange@redhat.com, linfeng23@huawei.com, groug@kaod.org, huangy81@chinatelecom.cn, lvivier@redhat.com, lizhijian@cn.fujitsu.com, peterx@redhat.com, vgoyal@redhat.com Subject: [PULL 12/20] virtiofsd: Fix xattr operations overwriting errno Date: Thu, 1 Jul 2021 15:15:37 +0100 Message-Id: <20210701141545.193571-13-dgilbert@redhat.com> In-Reply-To: <20210701141545.193571-1-dgilbert@redhat.com> References: <20210701141545.193571-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=216.205.24.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.402, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: leobras@redhat.com, stefanha@redhat.com, quintela@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Vivek Goyal getxattr/setxattr/removexattr/listxattr operations handle regualar and non-regular files differently. For the case of non-regular files we do fchdir(/proc/self/fd) and the xattr operation and then revert back to original working directory. After this we are saving errno and that's buggy because fchdir() will overwrite the errno. FCHDIR_NOFAIL(lo->proc_self_fd); ret = getxattr(procname, name, value, size); FCHDIR_NOFAIL(lo->root.fd); if (ret == -1) saverr = errno In above example, if getxattr() failed, we will still return 0 to caller as errno must have been written by FCHDIR_NOFAIL(lo->root.fd) call. Fix all such instances and capture "errno" early and save in "saverr" variable. Signed-off-by: Vivek Goyal Message-Id: <20210622150852.1507204-3-vgoyal@redhat.com> Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Greg Kurz Signed-off-by: Dr. David Alan Gilbert --- tools/virtiofsd/passthrough_ll.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index 9858e961d9..ccbda98c5a 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -2791,15 +2791,17 @@ static void lo_getxattr(fuse_req_t req, fuse_ino_t ino, const char *in_name, goto out_err; } ret = fgetxattr(fd, name, value, size); + saverr = ret == -1 ? errno : 0; } else { /* fchdir should not fail here */ FCHDIR_NOFAIL(lo->proc_self_fd); ret = getxattr(procname, name, value, size); + saverr = ret == -1 ? errno : 0; FCHDIR_NOFAIL(lo->root.fd); } if (ret == -1) { - goto out_err; + goto out; } if (size) { saverr = 0; @@ -2864,15 +2866,17 @@ static void lo_listxattr(fuse_req_t req, fuse_ino_t ino, size_t size) goto out_err; } ret = flistxattr(fd, value, size); + saverr = ret == -1 ? errno : 0; } else { /* fchdir should not fail here */ FCHDIR_NOFAIL(lo->proc_self_fd); ret = listxattr(procname, value, size); + saverr = ret == -1 ? errno : 0; FCHDIR_NOFAIL(lo->root.fd); } if (ret == -1) { - goto out_err; + goto out; } if (size) { saverr = 0; @@ -2998,15 +3002,15 @@ static void lo_setxattr(fuse_req_t req, fuse_ino_t ino, const char *in_name, goto out; } ret = fsetxattr(fd, name, value, size, flags); + saverr = ret == -1 ? errno : 0; } else { /* fchdir should not fail here */ FCHDIR_NOFAIL(lo->proc_self_fd); ret = setxattr(procname, name, value, size, flags); + saverr = ret == -1 ? errno : 0; FCHDIR_NOFAIL(lo->root.fd); } - saverr = ret == -1 ? errno : 0; - out: if (fd >= 0) { close(fd); @@ -3064,15 +3068,15 @@ static void lo_removexattr(fuse_req_t req, fuse_ino_t ino, const char *in_name) goto out; } ret = fremovexattr(fd, name); + saverr = ret == -1 ? errno : 0; } else { /* fchdir should not fail here */ FCHDIR_NOFAIL(lo->proc_self_fd); ret = removexattr(procname, name); + saverr = ret == -1 ? errno : 0; FCHDIR_NOFAIL(lo->root.fd); } - saverr = ret == -1 ? errno : 0; - out: if (fd >= 0) { close(fd); -- 2.31.1