Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:44671 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751602AbbKINFM (ORCPT ); Mon, 9 Nov 2015 08:05:12 -0500 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (Postfix) with ESMTPS id C2DDA14AA9 for ; Mon, 9 Nov 2015 13:05:11 +0000 (UTC) Received: from smallhat.boston.devel.redhat.com (vpn-54-90.rdu2.redhat.com [10.10.54.90]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id tA9D59kW019518 for ; Mon, 9 Nov 2015 08:05:11 -0500 From: Steve Dickson To: Linux NFS Mailing list Subject: [PATCH] gssd: use pthreads to handle upcalls Date: Mon, 9 Nov 2015 08:05:08 -0500 Message-Id: <1447074308-15823-2-git-send-email-steved@redhat.com> In-Reply-To: <1447074308-15823-1-git-send-email-steved@redhat.com> References: <1447074308-15823-1-git-send-email-steved@redhat.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Currently, to persevere global data over multiple mounts, the root process does not fork when handling an upcall. Instead of not-forking, create a pthread to handle the all upcalls since global data can be shared among threads. Signed-off-by: Steve Dickson --- aclocal/libpthread.m4 | 13 +++++++++++++ configure.ac | 3 +++ utils/gssd/Makefile.am | 3 ++- utils/gssd/gssd.c | 18 ++++++++++++++++-- utils/gssd/gssd.h | 2 ++ utils/gssd/gssd_proc.c | 30 ------------------------------ utils/gssd/krb5_util.c | 3 +++ 7 files changed, 39 insertions(+), 33 deletions(-) create mode 100644 aclocal/libpthread.m4 diff --git a/aclocal/libpthread.m4 b/aclocal/libpthread.m4 new file mode 100644 index 0000000..e87d2a0 --- /dev/null +++ b/aclocal/libpthread.m4 @@ -0,0 +1,13 @@ +dnl Checks for pthreads library and headers +dnl +AC_DEFUN([AC_LIBPTHREAD], [ + + dnl Check for library, but do not add -lpthreads to LIBS + AC_CHECK_LIB([pthread], [pthread_create], [LIBPTHREAD=-lpthread], + [AC_MSG_ERROR([libpthread not found.])]) + AC_SUBST(LIBPTHREAD) + + AC_CHECK_HEADERS([pthread.h], , + [AC_MSG_ERROR([libpthread headers not found.])]) + +])dnl diff --git a/configure.ac b/configure.ac index 25d2ba4..e0ecd61 100644 --- a/configure.ac +++ b/configure.ac @@ -385,6 +385,9 @@ if test "$enable_gss" = yes; then dnl Invoked after AC_KERBEROS_V5; AC_LIBRPCSECGSS needs to have KRBLIBS set AC_LIBRPCSECGSS + dnl Check for pthreads + AC_LIBPTHREAD + dnl librpcsecgss already has a dependency on libgssapi, dnl but we need to make sure we get the right version if test "$enable_gss" = yes; then diff --git a/utils/gssd/Makefile.am b/utils/gssd/Makefile.am index cb040b3..3f5f59a 100644 --- a/utils/gssd/Makefile.am +++ b/utils/gssd/Makefile.am @@ -49,7 +49,8 @@ gssd_LDADD = \ $(RPCSECGSS_LIBS) \ $(KRBLIBS) \ $(GSSAPI_LIBS) \ - $(LIBTIRPC) + $(LIBTIRPC) \ + $(LIBPTHREAD) gssd_LDFLAGS = \ $(KRBLDFLAGS) diff --git a/utils/gssd/gssd.c b/utils/gssd/gssd.c index e7cb07f..3c425ce 100644 --- a/utils/gssd/gssd.c +++ b/utils/gssd/gssd.c @@ -365,16 +365,30 @@ static void gssd_clnt_gssd_cb(int UNUSED(fd), short UNUSED(which), void *data) { struct clnt_info *clp = data; + pthread_t th; + int ret; - handle_gssd_upcall(clp); + ret = pthread_create(&th, NULL, (void *)handle_gssd_upcall, (void *)clp); + if (ret != 0) { + printerr(0, "pthread_create failed: ret %d: %s\n", ret, strerror(errno)); + return; + } + pthread_join(th, NULL); } static void gssd_clnt_krb5_cb(int UNUSED(fd), short UNUSED(which), void *data) { struct clnt_info *clp = data; + pthread_t th; + int ret; + + ret = pthread_create(&th, NULL, (void *)handle_krb5_upcall, (void *)clp); + if (ret != 0) { + printerr(0, "pthread_create failed: ret %d: %s\n", ret, strerror(errno)); + } - handle_krb5_upcall(clp); + pthread_join(th, NULL); } static struct clnt_info * diff --git a/utils/gssd/gssd.h b/utils/gssd/gssd.h index c6937c5..8677329 100644 --- a/utils/gssd/gssd.h +++ b/utils/gssd/gssd.h @@ -36,6 +36,7 @@ #include #include #include +#include #ifndef GSSD_PIPEFS_DIR #define GSSD_PIPEFS_DIR "/var/lib/nfs/rpc_pipefs" @@ -61,6 +62,7 @@ extern int root_uses_machine_creds; extern unsigned int context_timeout; extern unsigned int rpc_timeout; extern char *preferred_realm; +extern pthread_mutex_t ple_lock; struct clnt_info { TAILQ_ENTRY(clnt_info) list; diff --git a/utils/gssd/gssd_proc.c b/utils/gssd/gssd_proc.c index 1ef68d8..616082e 100644 --- a/utils/gssd/gssd_proc.c +++ b/utils/gssd/gssd_proc.c @@ -629,36 +629,6 @@ process_krb5_upcall(struct clnt_info *clp, uid_t uid, int fd, char *tgtname, if (uid != 0 || (uid == 0 && root_uses_machine_creds == 0 && service == NULL)) { - /* already running as uid 0 */ - if (uid == 0) - goto no_fork; - - pid = fork(); - switch(pid) { - case 0: - /* Child: fall through to rest of function */ - childpid = getpid(); - unsetenv("KRB5CCNAME"); - printerr(2, "CHILD forked pid %d \n", childpid); - break; - case -1: - /* fork() failed! */ - printerr(0, "WARNING: unable to fork() to handle" - "upcall: %s\n", strerror(errno)); - return; - default: - /* Parent: just wait on child to exit and return */ - do { - pid = wait(&err); - } while(pid == -1 && errno != -ECHILD); - - if (WIFSIGNALED(err)) - printerr(0, "WARNING: forked child was killed" - "with signal %d\n", WTERMSIG(err)); - return; - } -no_fork: - auth = krb5_not_machine_creds(clp, uid, tgtname, &downcall_err, &err, &rpc_clnt); if (err) diff --git a/utils/gssd/krb5_util.c b/utils/gssd/krb5_util.c index 8ef8184..7354dc7 100644 --- a/utils/gssd/krb5_util.c +++ b/utils/gssd/krb5_util.c @@ -128,6 +128,7 @@ /* Global list of principals/cache file names for machine credentials */ struct gssd_k5_kt_princ *gssd_k5_kt_princ_list = NULL; +pthread_mutex_t ple_lock; #ifdef HAVE_SET_ALLOWABLE_ENCTYPES int limit_to_legacy_enctypes = 0; @@ -586,10 +587,12 @@ get_ple_by_princ(krb5_context context, krb5_principal princ) /* Need to serialize list if we ever become multi-threaded! */ + pthread_mutex_lock(&ple_lock); ple = find_ple_by_princ(context, princ); if (ple == NULL) { ple = new_ple(context, princ); } + pthread_mutex_unlock(&ple_lock); return ple; } -- 2.4.3