Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:46078 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751749AbcKOTyi (ORCPT ); Tue, 15 Nov 2016 14:54:38 -0500 Subject: Re: [Libtirpc-devel] [PATCH rpcbind v2] Move default state-dir to a subdirectory of /tmp To: NeilBrown References: <877f8almcf.fsf@notabene.neil.brown.name> <20161111210034.GM21655@vapier.lan> <87polzj7sx.fsf@notabene.neil.brown.name> <87vavqilre.fsf@notabene.neil.brown.name> Cc: Mike Frysinger , Linux NFS Mailing List , libtirpc-devel@lists.sourceforge.net From: Steve Dickson Message-ID: Date: Tue, 15 Nov 2016 14:54:37 -0500 MIME-Version: 1.0 In-Reply-To: <87vavqilre.fsf@notabene.neil.brown.name> Content-Type: text/plain; charset=windows-1252 Sender: linux-nfs-owner@vger.kernel.org List-ID: On 11/14/2016 02:05 AM, NeilBrown wrote: > rpcbind can save state in a file to allow restart without forgetting > about running services. > > The default location is currently "/tmp" which is > not ideal for system files. It is particularly unpleasant > to put simple files there rather than creating a directory > to contain them. > > On a modern Linux system it is preferable to use /run, and there it is > even more consistent with practice to use a subdirectory. > > This directory needs to be create one each boot, and while there are > tools (e.g. systemd-tmpfiles) which can do that it is cleaner to keep > rpcbind self-contained and have it create the directory. > > So change the default location to /tmp/rpcbind, and create that > directory. If a different user-id is used, we need to create > and chown the directory before dropping privileges. We do this > with care so avoid chowning the wrong thing by mistake. > > Signed-off-by: NeilBrown > --- > > hi, > I realized that I hadn't allowed for the fact that rpcbind changes > it's uid, and we need to mkdir and chown before that. > I've also reverted the move to /run, but moved to /tmp/rpcbind > instead. A subdirectory is a good idea, even in /tmp. I'm beginning to think put these files into a directory call /tmp/rpcbind is not a good idea... Because if something in /tmp is called rpcbind (like a debugging binary ;-) ) the mkdirs will silently fail which is not good. Here is what I would like to do. Move the directory into /run then create the /run/rpcbind when it does not exist... I think that should play nicely in both the systemd worlds and non-systemd worlds Thoughts? steved. > > NeilBrown > > > configure.ac | 4 ++-- > src/rpcbind.c | 5 +++++ > src/rpcbind.h | 1 + > src/warmstart.c | 25 +++++++++++++++++++++---- > 4 files changed, 29 insertions(+), 6 deletions(-) > > diff --git a/configure.ac b/configure.ac > index f84921eb27fb..df931c720f93 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -22,8 +22,8 @@ AC_ARG_ENABLE([warmstarts], > AM_CONDITIONAL(WARMSTART, test x$enable_warmstarts = xyes) > > AC_ARG_WITH([statedir], > - AS_HELP_STRING([--with-statedir=ARG], [use ARG as state dir @<:@default=/tmp@:>@]) > - ,, [with_statedir=/tmp]) > + AS_HELP_STRING([--with-statedir=ARG], [use ARG as state dir @<:@default=/tmp/rpcbind@:>@]) > + ,, [with_statedir=/tmp/rpcbind]) > AC_SUBST([statedir], [$with_statedir]) > > AC_ARG_WITH([rpcuser], > diff --git a/src/rpcbind.c b/src/rpcbind.c > index 87ccdc27e4c9..8db8dfc17c27 100644 > --- a/src/rpcbind.c > +++ b/src/rpcbind.c > @@ -263,6 +263,11 @@ main(int argc, char *argv[]) > syslog(LOG_ERR, "cannot get uid of '%s': %m", id); > exit(1); > } > +#ifdef WARMSTART > + if (warmstart) { > + mkdir_warmstart(p->pw_uid); > + } > +#endif > if (setgid(p->pw_gid) == -1) { > syslog(LOG_ERR, "setgid to '%s' (%d) failed: %m", id, p->pw_gid); > exit(1); > diff --git a/src/rpcbind.h b/src/rpcbind.h > index 74f9591ae720..5b1a9bb8651a 100644 > --- a/src/rpcbind.h > +++ b/src/rpcbind.h > @@ -129,6 +129,7 @@ int is_localroot(struct netbuf *); > extern void pmap_service(struct svc_req *, SVCXPRT *); > #endif > > +void mkdir_warmstart(int uid); > void write_warmstart(void); > void read_warmstart(void); > > diff --git a/src/warmstart.c b/src/warmstart.c > index 122a058b7954..3a6bcb5e34e1 100644 > --- a/src/warmstart.c > +++ b/src/warmstart.c > @@ -45,19 +45,23 @@ > #include > #include > #include > +#include > > #include "rpcbind.h" > > -#ifndef RPCBIND_STATEDIR > -#define RPCBIND_STATEDIR "/tmp" > -#endif > - > /* These files keep the pmap_list and rpcb_list in XDR format */ > #define RPCBFILE RPCBIND_STATEDIR "/rpcbind.xdr" > #ifdef PORTMAP > #define PMAPFILE RPCBIND_STATEDIR "/portmap.xdr" > #endif > > +#ifndef O_DIRECTORY > +#define O_DIRECTORY 0 > +#endif > +#ifndef O_NOFOLLOW > +#define O_NOFOLLOW 0 > +#endif > + > static bool_t write_struct(char *, xdrproc_t, void *); > static bool_t read_struct(char *, xdrproc_t, void *); > > @@ -139,8 +143,21 @@ error: > } > > void > +mkdir_warmstart(int uid) > +{ > + if (mkdir(RPCBIND_STATEDIR, 0770) == 0) { > + int fd = open(RPCBIND_STATEDIR, O_RDONLY | O_DIRECTORY | O_NOFOLLOW); > + if (fd >= 0) { > + fchown(fd, uid, -1); > + close(fd); > + } > + } > +} > + > +void > write_warmstart() > { > + (void) mkdir(RPCBIND_STATEDIR, 0770); > (void) write_struct(RPCBFILE, (xdrproc_t)xdr_rpcblist_ptr, &list_rbl); > #ifdef PORTMAP > (void) write_struct(PMAPFILE, (xdrproc_t)xdr_pmaplist_ptr, &list_pml);