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=-7.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 D02E1C433DF for ; Fri, 17 Jul 2020 01:31:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A7E0D207BC for ; Fri, 17 Jul 2020 01:31:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726238AbgGQBb0 (ORCPT ); Thu, 16 Jul 2020 21:31:26 -0400 Received: from mx2.suse.de ([195.135.220.15]:48598 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726138AbgGQBb0 (ORCPT ); Thu, 16 Jul 2020 21:31:26 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 241B0AF73; Fri, 17 Jul 2020 01:31:29 +0000 (UTC) From: NeilBrown To: "J. Bruce Fields" Date: Fri, 17 Jul 2020 11:31:17 +1000 Cc: Jeff Layton , linux-nfs@vger.kernel.org Subject: Re: nfs4_show_superblock considered harmful :-) In-Reply-To: <20200717010301.GC18568@fieldses.org> References: <871rn38suc.fsf@notabene.neil.brown.name> <20200529220608.GA22758@fieldses.org> <87a71n7dek.fsf@notabene.neil.brown.name> <20200715185456.GE15543@fieldses.org> <20200716171958.GB18568@fieldses.org> <87tuy7vxeb.fsf@notabene.neil.brown.name> <20200717010301.GC18568@fieldses.org> Message-ID: <87r1tbvsey.fsf@notabene.neil.brown.name> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org --=-=-= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Thu, Jul 16 2020, J. Bruce Fields wrote: > On Fri, Jul 17, 2020 at 09:43:40AM +1000, NeilBrown wrote: >> On Thu, Jul 16 2020, J. Bruce Fields wrote: >> > --- a/fs/nfsd/nfs4state.c >> > +++ b/fs/nfsd/nfs4state.c >> > @@ -507,6 +507,16 @@ find_any_file(struct nfs4_file *f) >> > return ret; >> > } >> >=20=20 >> > +static struct nfsd_file *find_deleg_file(struct nfs4_file *f) >> > +{ >> > + struct nfsd_file *ret; >> > + >> > + spin_lock(&f->fi_lock); >> > + ret =3D nfsd_file_get(f->fi_deleg_file); >>=20 >> A test on f->fi_deleg_file being non-NULL would make this look safer. >> It would also make the subsequent test on the return value appear sane. > > Yes, thanks!-b. > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index c2a2e56c896d..6e8811e7c134 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -509,10 +509,11 @@ find_any_file(struct nfs4_file *f) >=20=20 > static struct nfsd_file *find_deleg_file(struct nfs4_file *f) > { > - struct nfsd_file *ret; > + struct nfsd_file *ret =3D NULL; >=20=20 > spin_lock(&f->fi_lock); > - ret =3D nfsd_file_get(f->fi_deleg_file); > + if (f->fi_deleg_file) > + ret =3D nfsd_file_get(f->fi_deleg_file); > spin_unlock(&f->fi_lock); > return ret; > } Reviewed-by: NeilBrown for the whole patch. Thanks, NeilBrown --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEG8Yp69OQ2HB7X0l6Oeye3VZigbkFAl8Q/2UACgkQOeye3VZi gbk8JRAAixYbaorls05aJDqYVwSKTysBTCJCPKEQFtEjRcmOuCQeVwgQWfonJxag 1Wp9irpv3BT+X2117rZqt47V9wBUFKCJPoPZlHNRevncWUgooq1oNDtC550HjSac HQy9fMGNy3LCj4DgB9bLIFLIKKhRAkxxgzhc8ROzn3bbjQm11ie6gxPpXl7WBh9K o3nzi96dsfP5tIE/qi1NcEG1qgRlQVdRslPZV9ZuGFGZ5kSez3dQvGZzBg2YHu9K d1k/WZoxiH+mw/SG+pTELokYqRmRkHVtJlYQgpsCy9Fk9uMtEImWQNVWjHAQzHEK cy6Rq3oMf4SaTZnBfa+c/Z+cfCoAlb41FMXpgv2SpKAC3wh18s/7kyrdhFfGN0Mh 8/1W7rH7SqxRDpDqsPx4AMn66KwR7o95rDZ03sa/aLuRYhK/Tw4BKHwj7yAZASgL 1l30Hc+WWqE5F1oEptas9wpKxZCOasZpgjqsXtwTdwnZwMbzi2Ft2+Go2RcSIJv4 WOQMY8D0h1F3pw/atY3mpZXotqcdeDG2pcWaOkP+nQnPYmwOqlV8yosa2fqNaqsS 1d8xztD0LMm7J2vng/iPsSyRoF4JDDxIhdyuxsGJx9sdprWdPF1uvFZNgNh+bg6u xFtbQwoy99p19iCmWIageDwc/1FmHS8M2Hhku2k5AlG4nlWi/IE= =Uzyt -----END PGP SIGNATURE----- --=-=-=--