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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 1A3C3C4724C for ; Fri, 1 May 2020 19:21:00 +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 D52632166E for ; Fri, 1 May 2020 19:20:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="PnUxdZKe" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D52632166E 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]:47412 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jUbDX-00056K-1i for qemu-devel@archiver.kernel.org; Fri, 01 May 2020 15:20:59 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33422) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jUb8A-0006kD-Jn for qemu-devel@nongnu.org; Fri, 01 May 2020 15:15:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.90_1) (envelope-from ) id 1jUb89-0000Aj-Ue for qemu-devel@nongnu.org; Fri, 01 May 2020 15:15:26 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:22912 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jUb89-0000A4-EU for qemu-devel@nongnu.org; Fri, 01 May 2020 15:15:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588360524; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4EXg3g0TJQ0fzkN/YF/vUs7KPqWl/4bai/hbrgPx4Kw=; b=PnUxdZKeuTfetF4QnpWq/u1pfZ6U/u+645Ar5Kjt1sBN1M3AZpMbPTOv3aJH63eJ2oC2BX mDSygKUMW8/RVjAUQmOQ0Y8HjAeeak6Iz/3nYzpps76hI6zNLcoQPWq8TJzWJ2V88T0xNy ylCVMRpiGEFAenYPpZUMDMBlyugSxXA= 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-36-C1D59UdIPb2edws58G-W0Q-1; Fri, 01 May 2020 15:15:22 -0400 X-MC-Unique: C1D59UdIPb2edws58G-W0Q-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 196AFA0C13; Fri, 1 May 2020 19:15:21 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-112-191.ams2.redhat.com [10.36.112.191]) by smtp.corp.redhat.com (Postfix) with ESMTP id D04E910013BD; Fri, 1 May 2020 19:15:19 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, stefanha@redhat.com, yavrahami@paloaltonetworks.com, mszeredi@redhat.com, mreitz@redhat.com Subject: [PULL 6/6] virtiofsd: drop all capabilities in the wait parent process Date: Fri, 1 May 2020 20:15:00 +0100 Message-Id: <20200501191500.126432-7-dgilbert@redhat.com> In-Reply-To: <20200501191500.126432-1-dgilbert@redhat.com> References: <20200501191500.126432-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=205.139.110.120; envelope-from=dgilbert@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/01 08:22:51 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.120 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Stefan Hajnoczi All this process does is wait for its child. No capabilities are needed. Signed-off-by: Stefan Hajnoczi Reviewed-by: Philippe Mathieu-Daud=C3=A9 Signed-off-by: Dr. David Alan Gilbert --- tools/virtiofsd/passthrough_ll.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough= _ll.c index e49650b63d..3ba1d90984 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -2530,6 +2530,17 @@ static void print_capabilities(void) printf("}\n"); } =20 +/* + * Drop all Linux capabilities because the wait parent process only needs = to + * sit in waitpid(2) and terminate. + */ +static void setup_wait_parent_capabilities(void) +{ + capng_setpid(syscall(SYS_gettid)); + capng_clear(CAPNG_SELECT_BOTH); + capng_apply(CAPNG_SELECT_BOTH); +} + /* * Move to a new mount, net, and pid namespaces to isolate this process. */ @@ -2563,6 +2574,8 @@ static void setup_namespaces(struct lo_data *lo, stru= ct fuse_session *se) pid_t waited; int wstatus; =20 + setup_wait_parent_capabilities(); + /* The parent waits for the child */ do { waited =3D waitpid(child, &wstatus, 0); --=20 2.26.2