From patchwork Fri Apr 9 10:06:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg Kurz X-Patchwork-Id: 1464271 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=) 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 4FGv1l1lMDz9sW5 for ; Fri, 9 Apr 2021 20:07:05 +1000 (AEST) Received: from localhost ([::1]:36244 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lUo2Y-0004KD-HH for incoming@patchwork.ozlabs.org; Fri, 09 Apr 2021 06:07:02 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43458) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUo2H-0004K7-8m for qemu-devel@nongnu.org; Fri, 09 Apr 2021 06:06:45 -0400 Received: from us-smtp-delivery-44.mimecast.com ([207.211.30.44]:60840) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUo2F-0003pf-Ew for qemu-devel@nongnu.org; Fri, 09 Apr 2021 06:06:45 -0400 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-29--VfArW0eNkCQDIEwQfDM9g-1; Fri, 09 Apr 2021 06:06:37 -0400 X-MC-Unique: -VfArW0eNkCQDIEwQfDM9g-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7C97B6D4E0; Fri, 9 Apr 2021 10:06:36 +0000 (UTC) Received: from bahia.redhat.com (ovpn-112-136.ams2.redhat.com [10.36.112.136]) by smtp.corp.redhat.com (Postfix) with ESMTP id AA80960BE5; Fri, 9 Apr 2021 10:06:28 +0000 (UTC) From: Greg Kurz To: qemu-devel@nongnu.org Subject: [PATCH] virtiofsd: Fix side-effect in assert() Date: Fri, 9 Apr 2021 12:06:27 +0200 Message-Id: <20210409100627.451573-1-groug@kaod.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=groug@kaod.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kaod.org Received-SPF: softfail client-ip=207.211.30.44; envelope-from=groug@kaod.org; helo=us-smtp-delivery-44.mimecast.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_SOFTFAIL=0.665 autolearn=no 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: virtio-fs@redhat.com, misono.tomohiro@jp.fujitsu.com, "Dr. David Alan Gilbert" , Stefan Hajnoczi , Greg Kurz Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" It is bad practice to put an expression with a side-effect in assert() because the side-effect won't happen if the code is compiled with -DNDEBUG. Use an intermediate variable. Consolidate this in an macro to have proper line numbers when the assertion is hit. virtiofsd: ../../tools/virtiofsd/passthrough_ll.c:2797: lo_getxattr: Assertion `fchdir_res == 0' failed. Aborted 2796 /* fchdir should not fail here */ =>2797 FCHDIR_NOFAIL(lo->proc_self_fd); 2798 ret = getxattr(procname, name, value, size); 2799 FCHDIR_NOFAIL(lo->root.fd); Fixes: bdfd66788349 ("virtiofsd: Fix xattr operations") Cc: misono.tomohiro@jp.fujitsu.com Signed-off-by: Greg Kurz Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Vivek Goyal Reviewed-by: Wainer dos Santos Moschetta Reviewed-by: Alex Bennée --- tools/virtiofsd/passthrough_ll.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index 1553d2ef454f..6592f96f685e 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -2723,6 +2723,11 @@ static int xattr_map_server(const struct lo_data *lo, const char *server_name, return -ENODATA; } +#define FCHDIR_NOFAIL(fd) do { \ + int fchdir_res = fchdir(fd); \ + assert(fchdir_res == 0); \ + } while (0) + static void lo_getxattr(fuse_req_t req, fuse_ino_t ino, const char *in_name, size_t size) { @@ -2789,9 +2794,9 @@ static void lo_getxattr(fuse_req_t req, fuse_ino_t ino, const char *in_name, ret = fgetxattr(fd, name, value, size); } else { /* fchdir should not fail here */ - assert(fchdir(lo->proc_self_fd) == 0); + FCHDIR_NOFAIL(lo->proc_self_fd); ret = getxattr(procname, name, value, size); - assert(fchdir(lo->root.fd) == 0); + FCHDIR_NOFAIL(lo->root.fd); } if (ret == -1) { @@ -2864,9 +2869,9 @@ static void lo_listxattr(fuse_req_t req, fuse_ino_t ino, size_t size) ret = flistxattr(fd, value, size); } else { /* fchdir should not fail here */ - assert(fchdir(lo->proc_self_fd) == 0); + FCHDIR_NOFAIL(lo->proc_self_fd); ret = listxattr(procname, value, size); - assert(fchdir(lo->root.fd) == 0); + FCHDIR_NOFAIL(lo->root.fd); } if (ret == -1) { @@ -3000,9 +3005,9 @@ static void lo_setxattr(fuse_req_t req, fuse_ino_t ino, const char *in_name, ret = fsetxattr(fd, name, value, size, flags); } else { /* fchdir should not fail here */ - assert(fchdir(lo->proc_self_fd) == 0); + FCHDIR_NOFAIL(lo->proc_self_fd); ret = setxattr(procname, name, value, size, flags); - assert(fchdir(lo->root.fd) == 0); + FCHDIR_NOFAIL(lo->root.fd); } saverr = ret == -1 ? errno : 0; @@ -3066,9 +3071,9 @@ static void lo_removexattr(fuse_req_t req, fuse_ino_t ino, const char *in_name) ret = fremovexattr(fd, name); } else { /* fchdir should not fail here */ - assert(fchdir(lo->proc_self_fd) == 0); + FCHDIR_NOFAIL(lo->proc_self_fd); ret = removexattr(procname, name); - assert(fchdir(lo->root.fd) == 0); + FCHDIR_NOFAIL(lo->root.fd); } saverr = ret == -1 ? errno : 0;