From patchwork Mon Mar 15 20:12:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Dr. David Alan Gilbert" X-Patchwork-Id: 1453550 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=BseB8/ui; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 4Dznl71FDCz9sTD for ; Tue, 16 Mar 2021 07:17:07 +1100 (AEDT) Received: from localhost ([::1]:48762 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lLteD-0005Dm-5B for incoming@patchwork.ozlabs.org; Mon, 15 Mar 2021 16:17:05 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45348) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lLta1-0000RQ-G8 for qemu-devel@nongnu.org; Mon, 15 Mar 2021 16:12:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:26807) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lLtZx-0006N5-Qi for qemu-devel@nongnu.org; Mon, 15 Mar 2021 16:12:45 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1615839160; 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=8VrXlwaog+5eg0faNDCbHzcaVezRM45liYf66o9tL1I=; b=BseB8/uiGKgDknSQ/xudlIA5T1cx1q7K08J/WLCl8+/573MaqX8FmydoTUplzDZB1ptqwB BbFIYsLK+rDtw7UVTVuGauX0SmUFR7lRAvqJH+Y+MFcm5SellC317hDvs1DELPj9jMYLqi idmICKQMrJe5i1ccNvQPAqJWKtV4fmk= 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-51-fuFGzVSQOlCZp8McLUvcIQ-1; Mon, 15 Mar 2021 16:12:38 -0400 X-MC-Unique: fuFGzVSQOlCZp8McLUvcIQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 71DCD18460E1; Mon, 15 Mar 2021 20:12:37 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-114-235.ams2.redhat.com [10.36.114.235]) by smtp.corp.redhat.com (Postfix) with ESMTP id BF79C5D751; Mon, 15 Mar 2021 20:12:35 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, groug@kaod.org, vgoyal@redhat.com, wanghao232@huawei.com, ma.mandourr@gmail.com Subject: [PULL 4/9] virtiofsd: Don't allow empty paths in lookup_name() Date: Mon, 15 Mar 2021 20:12:10 +0000 Message-Id: <20210315201215.222539-5-dgilbert@redhat.com> In-Reply-To: <20210315201215.222539-1-dgilbert@redhat.com> References: <20210315201215.222539-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 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 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: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.25, 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_H3=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: stefanha@redhat.com, peterx@redhat.com, quintela@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Greg Kurz When passed an empty filename, lookup_name() returns the inode of the parent directory, unless the parent is the root in which case the st_dev doesn't match and lo_find() returns NULL. This is because lookup_name() passes AT_EMPTY_PATH down to fstatat() or statx(). This behavior doesn't quite make sense because users of lookup_name() then pass the name to unlinkat(), renameat() or renameat2(), all of which will always fail on empty names. Drop AT_EMPTY_PATH from the flags in lookup_name() so that it has the consistent behavior of "returning an existing child inode or NULL" for all directories. Signed-off-by: Greg Kurz Message-Id: <20210312141003.819108-2-groug@kaod.org> Reviewed-by: Connor Kuehl Reviewed-by: Vivek Goyal Signed-off-by: Dr. David Alan Gilbert --- tools/virtiofsd/passthrough_ll.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index b07101d8eb..cf453eea9b 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -1330,8 +1330,7 @@ static struct lo_inode *lookup_name(fuse_req_t req, fuse_ino_t parent, return NULL; } - res = do_statx(lo, dir->fd, name, &attr, - AT_EMPTY_PATH | AT_SYMLINK_NOFOLLOW, &mnt_id); + res = do_statx(lo, dir->fd, name, &attr, AT_SYMLINK_NOFOLLOW, &mnt_id); lo_inode_put(lo, &dir); if (res == -1) { return NULL;