From patchwork Mon Jun 17 23:02:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: DJ Delorie X-Patchwork-Id: 33166 Received: (qmail 128890 invoked by alias); 17 Jun 2019 23:02:25 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 128882 invoked by uid 89); 17 Jun 2019 23:02:25 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-16.9 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, SPF_HELO_PASS autolearn=ham version=3.3.1 spammy= X-HELO: mx1.redhat.com From: DJ Delorie To: Florian Weimer Cc: libc-alpha@sourceware.org Subject: Re: nss_db: reset mapping after last get*ent In-Reply-To: <87o92wt1l9.fsf@mid.deneb.enyo.de> (message from Florian Weimer on Mon, 17 Jun 2019 22:10:26 +0200) Date: Mon, 17 Jun 2019 19:02:16 -0400 Message-ID: MIME-Version: 1.0 Florian Weimer writes: > This needs a bug in Bugzilla and, ideally, a test case. How's this? https://sourceware.org/bugzilla/show_bug.cgi?id=24695 nss_db allows for getpwent et al to be called without a set*ent, but it only works once. After the last get*ent a set*ent is required to restart, because the end*ent did not properly reset the module. Resetting it to NULL allows for a proper restart. The test case runs "makedb" inside the testroot, so needs selinux DSOs installed. * nss/nss_db/db-open.c (internal_endent): Reset mapping to NULL. * nss/tst-nss-db-endpwent.c: New. * nss/tst-nss-db-endpwent.root: New. * nss/Makefile: Add new test. * support/links-dso-program-c.c: Add selinux dependency. * support/links-dso-program.cc: Add selinux dependency. * support/Makefile: Build those with -lselinux if enabled. diff --git a/nss/Makefile b/nss/Makefile index 95081bddc5..15fc410cf1 100644 --- a/nss/Makefile +++ b/nss/Makefile @@ -61,7 +61,8 @@ xtests = bug-erange tests-container = \ tst-nss-test3 \ - tst-nss-files-hosts-long + tst-nss-files-hosts-long \ + tst-nss-db-endpwent # Tests which need libdl ifeq (yes,$(build-shared)) diff --git a/nss/nss_db/db-open.c b/nss/nss_db/db-open.c index 8a83d6b930..f7c53b4486 100644 --- a/nss/nss_db/db-open.c +++ b/nss/nss_db/db-open.c @@ -64,4 +64,5 @@ void internal_endent (struct nss_db_map *mapping) { munmap (mapping->header, mapping->len); + mapping->header = NULL; } diff --git a/nss/tst-nss-db-endpwent.c b/nss/tst-nss-db-endpwent.c new file mode 100644 index 0000000000..accc7f0932 --- /dev/null +++ b/nss/tst-nss-db-endpwent.c @@ -0,0 +1,47 @@ +/* Test for endpwent->getpwent crash. + Copyright (C) 2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include + +#include + +static void +try_it (void) +{ + struct passwd *pw; + + /* setpwent() is intentionally omitted here. */ + + while ((pw = getpwent ()) != NULL) + ; + + endpwent (); +} + +static int +do_test (void) +{ + system ("/usr/bin/makedb -o /var/db/passwd.db /var/db/passwd.in"); + try_it (); + try_it (); + + return 0; +} +#include diff --git a/nss/tst-nss-db-endpwent.root/etc/nsswitch.conf b/nss/tst-nss-db-endpwent.root/etc/nsswitch.conf new file mode 100644 index 0000000000..593ffc564a --- /dev/null +++ b/nss/tst-nss-db-endpwent.root/etc/nsswitch.conf @@ -0,0 +1 @@ +passwd: db diff --git a/nss/tst-nss-db-endpwent.root/var/db/passwd.in b/nss/tst-nss-db-endpwent.root/var/db/passwd.in new file mode 100644 index 0000000000..98f39126ef --- /dev/null +++ b/nss/tst-nss-db-endpwent.root/var/db/passwd.in @@ -0,0 +1,4 @@ +.root root:x:0:0:root:/root:/bin/bash +=0 root:x:0:0:root:/root:/bin/bash +.bin bin:x:1:1:bin:/bin:/sbin/nologin +=1 bin:x:1:1:bin:/bin:/sbin/nologin diff --git a/support/Makefile b/support/Makefile index 56c1ed43bb..ab66913a02 100644 --- a/support/Makefile +++ b/support/Makefile @@ -191,6 +191,11 @@ LINKS_DSO_PROGRAM = links-dso-program LDLIBS-links-dso-program = -lstdc++ -lgcc -lgcc_s $(libunwind) endif +ifeq (yes,$(have-selinux)) +LDLIBS-$(LINKS_DSO_PROGRAM) += -lselinux +endif + + LDLIBS-test-container = $(libsupport) others += test-container diff --git a/support/links-dso-program-c.c b/support/links-dso-program-c.c index d28a28a0d0..6043b8652b 100644 --- a/support/links-dso-program-c.c +++ b/support/links-dso-program-c.c @@ -1,9 +1,18 @@ #include +/* makedb needs selinux dso's. */ +#ifdef HAVE_SELINUX +# include +int sel; +#endif + int main (int argc, char **argv) { /* Complexity to keep gcc from optimizing this away. */ printf ("This is a test %s.\n", argc > 1 ? argv[1] : "null"); +#ifdef HAVE_SELINUX + sel = is_selinux_enabled (); +#endif return 0; } diff --git a/support/links-dso-program.cc b/support/links-dso-program.cc index dba6976c06..abb04f219a 100644 --- a/support/links-dso-program.cc +++ b/support/links-dso-program.cc @@ -1,5 +1,11 @@ #include +/* makedb needs selinux dso's. */ +#ifdef HAVE_SELINUX +# include +int sel; +#endif + using namespace std; int @@ -7,5 +13,8 @@ main (int argc, char **argv) { /* Complexity to keep gcc from optimizing this away. */ cout << (argc > 1 ? argv[1] : "null"); +#ifdef HAVE_SELINUX + sel = is_selinux_enabled (); +#endif return 0; }