From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx1.redhat.com ([209.132.183.28]:33044 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751752Ab2FLMWj (ORCPT ); Tue, 12 Jun 2012 08:22:39 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q5CCMdB3021700 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Tue, 12 Jun 2012 08:22:39 -0400 Message-ID: <4FD7347A.6010700@redhat.com> Date: Tue, 12 Jun 2012 14:22:18 +0200 From: Harald Hoyer MIME-Version: 1.0 To: Jeff Layton CC: steved@redhat.com, linux-nfs@vger.kernel.org Subject: Re: [PATCH] Before clearing the capability bounding set, check if we have the cap References: <1339501866-18967-1-git-send-email-harald@redhat.com> <20120612081725.0322bdd2@tlielax.poochiereds.net> In-Reply-To: <20120612081725.0322bdd2@tlielax.poochiereds.net> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-nfs-owner@vger.kernel.org List-ID: On 06/12/2012 02:17 PM, Jeff Layton wrote: > On Tue, 12 Jun 2012 13:51:06 +0200 > harald@redhat.com wrote: > >> From: Harald Hoyer >> >> PR_CAPBSET_DROP can return EINVAL, if an older kernel does support >> some capabilities, which are defined by CAP_LAST_CAP, which results in >> a failure of the service. >> >> For example kernel 3.4 errors on CAP_EPOLLWAKEUP, which was newly >> introduced in 3.5. >> >> So, for future capabilities, we clear until we get an EINVAL for >> PR_CAPBSET_READ. >> --- >> support/nsm/file.c | 2 +- >> utils/nfsdcld/nfsdcld.c | 4 ++-- >> 2 files changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/support/nsm/file.c b/support/nsm/file.c >> index 5476446..4711c2c 100644 >> --- a/support/nsm/file.c >> +++ b/support/nsm/file.c >> @@ -386,7 +386,7 @@ prune_bounding_set(void) >> } >> >> /* prune the bounding set to nothing */ >> - for (i = 0; i <= CAP_LAST_CAP; ++i) { >> + for (i = 0; prctl(PR_CAPBSET_READ, i, 0, 0, 0) >=0 ; ++i) { >> ret = prctl(PR_CAPBSET_DROP, i, 0, 0, 0); >> if (ret) { >> xlog(L_ERROR, "Unable to prune capability %lu from " >> diff --git a/utils/nfsdcld/nfsdcld.c b/utils/nfsdcld/nfsdcld.c >> index e7af4e3..473d069 100644 >> --- a/utils/nfsdcld/nfsdcld.c >> +++ b/utils/nfsdcld/nfsdcld.c >> @@ -102,8 +102,8 @@ cld_set_caps(void) >> } >> >> /* prune the bounding set to nothing */ >> - for (i = 0; i <= CAP_LAST_CAP; ++i) { >> - ret = prctl(PR_CAPBSET_DROP, i); >> + for (i = 0; prctl(PR_CAPBSET_READ, i, 0, 0, 0) >= 0 ; ++i) { >> + ret = prctl(PR_CAPBSET_DROP, i, 0, 0, 0); >> if (ret) { >> xlog(L_ERROR, "Unable to prune capability %lu from " >> "bounding set: %m", i); > > Thanks, looks like a reasonable method. Did you find this by > inspection, or did you or someone else hit the problem? > > Reviewed-by: Jeff Layton > I am currently running rawhide with kernel 3.4.0 and rpc.statd failed. rpc.statd[19338]: Unable to prune capability 36 from bounding set: Invalid argument