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=-13.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 E387FC2BA83 for ; Wed, 12 Feb 2020 13:52:04 +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 ACCB92082F for ; Wed, 12 Feb 2020 13:52:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="EwD8zBHi" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ACCB92082F 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]:38180 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j1sQt-0004Sv-S4 for qemu-devel@archiver.kernel.org; Wed, 12 Feb 2020 08:52:03 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:38948) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j1sGl-0003fl-Fb for qemu-devel@nongnu.org; Wed, 12 Feb 2020 08:41:36 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j1sGk-0002BN-83 for qemu-devel@nongnu.org; Wed, 12 Feb 2020 08:41:35 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:56702 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j1sGk-0002Ay-41 for qemu-devel@nongnu.org; Wed, 12 Feb 2020 08:41:34 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1581514893; 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=OptecfwUnA3Ryc1Wec8FFJAnQ1YzCfxvleXptvY7IW8=; b=EwD8zBHiv2yFSQXduoRVt80NDKxb7/maju17pcP+To9AVZhQVn1VE5pQ0R20FxbkY5yMme uMbXqGwEtSwMI46QlHHsOaXdLS/qo4U0ePfxvclvHtL/YMExyIXqJlcHMdzLu0HdOEAmwi rb6j1ZBVu7OnmFmZuFk7ry2RFJtchuA= 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-173-xMbpzfKsMAyhzdrA-Lq7Rw-1; Wed, 12 Feb 2020 08:41:30 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 86F2E10054E3; Wed, 12 Feb 2020 13:41:29 +0000 (UTC) Received: from localhost (unknown [10.36.118.78]) by smtp.corp.redhat.com (Postfix) with ESMTP id EAC6719C6A; Wed, 12 Feb 2020 13:41:28 +0000 (UTC) Date: Wed, 12 Feb 2020 13:41:28 +0000 From: "Richard W.M. Jones" To: Eric Blake Subject: Re: [PATCH] nbd-client: Support leading / in NBD URI Message-ID: <20200212134128.GY3888@redhat.com> References: <20200212023101.1162686-1-eblake@redhat.com> MIME-Version: 1.0 In-Reply-To: <20200212023101.1162686-1-eblake@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: xMbpzfKsMAyhzdrA-Lq7Rw-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 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: , Cc: Kevin Wolf , vsementsov@virtuozzo.com, qemu-devel@nongnu.org, "open list:Network Block Dev..." , Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Feb 11, 2020 at 08:31:01PM -0600, Eric Blake wrote: > The NBD URI specification [1] states that only one leading slash at > the beginning of the URI path component is stripped, not all such > slashes. This becomes important to a patch I just proposed to nbdkit > [2], which would allow the exportname to select a file embedded within > an ext2 image: ext2fs demands an absolute pathname beginning with '/', > and because qemu was inadvertantly stripping it, my nbdkit patch had > to work around the behavior. >=20 > [1] https://github.com/NetworkBlockDevice/nbd/blob/master/doc/uri.md > [2] https://www.redhat.com/archives/libguestfs/2020-February/msg00109.htm= l >=20 > Note that the qemu bug only affects handling of URIs such as > nbd://host:port//abs/path (where '/abs/path' should be the export > name); it is still possible to use --image-opts and pass the desired > export name with a leading slash directly through JSON even without > this patch. >=20 > Signed-off-by: Eric Blake > --- > block/nbd.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) >=20 > diff --git a/block/nbd.c b/block/nbd.c > index d085554f21ea..82f9b7ef50a5 100644 > --- a/block/nbd.c > +++ b/block/nbd.c > @@ -1516,8 +1516,10 @@ static int nbd_parse_uri(const char *filename, QDi= ct *options) > goto out; > } >=20 > - p =3D uri->path ? uri->path : "/"; > - p +=3D strspn(p, "/"); > + p =3D uri->path ? uri->path : ""; > + if (p[0] =3D=3D '/') { > + p++; > + } > if (p[0]) { > qdict_put_str(options, "export", p); > } Looks reasonable, ACK. Rich. --=20 Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjon= es Read my programming and virtualization blog: http://rwmj.wordpress.com virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://people.redhat.com/~rjones/virt-top