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,URIBL_BLOCKED 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 59E2CC433ED for ; Fri, 9 Apr 2021 13:32:51 +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 03A1361104 for ; Fri, 9 Apr 2021 13:32:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 03A1361104 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]:53650 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lUrFi-0005mW-4g for qemu-devel@archiver.kernel.org; Fri, 09 Apr 2021 09:32:50 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35358) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUrDX-00037a-Dx for qemu-devel@nongnu.org; Fri, 09 Apr 2021 09:30:36 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:23335) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUrDF-0006SB-VJ for qemu-devel@nongnu.org; Fri, 09 Apr 2021 09:30:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617975011; 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: in-reply-to:in-reply-to:references:references; bh=FLwwh2iBnnSqAkADEoECbYwn1f8BinBaw0zvDIBN2ug=; b=E5noi6o3M4D+K/aCrpFvrm3QqLzJgEMZxZLP4mKYcva50X4wRMca//rbqVhTxmcXXXNuSQ NgozxS1wsZhvYRuDqNXhBwJObWmoXc21Ltt0mvvxNz3/8ViHu2LnsxRCGCup5uzi6dNX7g 43Hv81KFdzVanNC17NvHXcUuDm7HT4k= 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-364-Q3uRp-PjPwuzNbztJb6ZmA-1; Fri, 09 Apr 2021 09:30:09 -0400 X-MC-Unique: Q3uRp-PjPwuzNbztJb6ZmA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9D54984B9A1; Fri, 9 Apr 2021 13:30:07 +0000 (UTC) Received: from horse.redhat.com (ovpn-116-67.rdu2.redhat.com [10.10.116.67]) by smtp.corp.redhat.com (Postfix) with ESMTP id 66C765C1A1; Fri, 9 Apr 2021 13:30:07 +0000 (UTC) Received: by horse.redhat.com (Postfix, from userid 10451) id EEDB822054F; Fri, 9 Apr 2021 09:30:06 -0400 (EDT) Date: Fri, 9 Apr 2021 09:30:06 -0400 From: Vivek Goyal To: Greg Kurz Subject: Re: [Virtio-fs] [PATCH] virtiofsd: Fix side-effect in assert() Message-ID: <20210409133006.GC1111800@redhat.com> References: <20210409100627.451573-1-groug@kaod.org> MIME-Version: 1.0 In-Reply-To: <20210409100627.451573-1-groug@kaod.org> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=vgoyal@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=170.10.133.124; envelope-from=vgoyal@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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: virtio-fs@redhat.com, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Fri, Apr 09, 2021 at 12:06:27PM +0200, Greg Kurz wrote: > 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 Looks good to me. Reviewed-by: Vivek Goyal Vivek > --- > 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; > -- > 2.26.3 > > _______________________________________________ > Virtio-fs mailing list > Virtio-fs@redhat.com > https://listman.redhat.com/mailman/listinfo/virtio-fs