From patchwork Mon Mar 15 13:32:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 42545 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id CF2C43857817; Mon, 15 Mar 2021 13:32:42 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org CF2C43857817 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1615815162; bh=CRDCbZw8xKbVYU7JnXwqHK75475SFKqXp35VQhnGL8k=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:From; b=OVke6pIcXQwutpdboGwd879ku47Bfa96Sxuc0BBvr05wKF5z/t3Qub7uD8gt4RSkv O286y/70EBI8gEGqTA0JHNztcWaXdzOC4IW/MoofJtnz9puYmlQ7ubWlZ3rZm9nDfe 2MbTXdZKL+7gOm/FdCENIybwT2al/Q1yZnsY3w90= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by sourceware.org (Postfix) with ESMTP id ABDB73857C7E for ; Mon, 15 Mar 2021 13:32:39 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org ABDB73857C7E Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-171-X6qk572sOfemtP_YZ2lusQ-1; Mon, 15 Mar 2021 09:32:37 -0400 X-MC-Unique: X6qk572sOfemtP_YZ2lusQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 41B001084D68 for ; Mon, 15 Mar 2021 13:32:36 +0000 (UTC) Received: from oldenburg.str.redhat.com (ovpn-112-163.ams2.redhat.com [10.36.112.163]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7F46A100239A for ; Mon, 15 Mar 2021 13:32:35 +0000 (UTC) To: libc-alpha@sourceware.org Subject: [PATCH v2] elf: ld.so --help calls _dl_init_paths without a main map [BZ #27577] Date: Mon, 15 Mar 2021 14:32:41 +0100 Message-ID: <878s6ov8xy.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-12.5 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Florian Weimer via Libc-alpha From: Florian Weimer Reply-To: Florian Weimer Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" In this case, use the link map of the dynamic loader itself as a replacement. This is more than just a hack: if we ever support DT_RUNPATH/DT_RPATH for the dynamic loader, reporting it for ld.so --help (without further command line arguments) would be the right thing to do. Fixes commit 332421312576bd7095e70589154af99b124dd2d1 ("elf: Always set l in _dl_init_paths (bug 23462)"). --- v2: Switch to just one test for checking ld.so --help output. elf/Makefile | 18 ++++++++++++++++-- elf/dl-load.c | 8 +++++++- 2 files changed, 23 insertions(+), 3 deletions(-) diff --git a/elf/Makefile b/elf/Makefile index 4c9e63dac9..ba4689a7fa 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -245,7 +245,7 @@ tests += $(tests-execstack-$(have-z-execstack)) ifeq ($(run-built-tests),yes) tests-special += $(objpfx)tst-leaks1-mem.out \ $(objpfx)tst-leaks1-static-mem.out $(objpfx)noload-mem.out \ - $(objpfx)tst-ldconfig-X.out + $(objpfx)tst-ldconfig-X.out $(objpfx)tst-rtld-help.out endif tlsmod17a-suffixes = 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 tlsmod18a-suffixes = 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 @@ -433,7 +433,8 @@ endif ifeq (yes,$(build-shared)) ifeq ($(run-built-tests),yes) tests-special += $(objpfx)tst-pathopt.out $(objpfx)tst-rtld-load-self.out \ - $(objpfx)tst-rtld-preload.out $(objpfx)argv0test.out + $(objpfx)tst-rtld-preload.out $(objpfx)argv0test.out \ + $(objpfx)tst-rtld-help.out endif tests-special += $(objpfx)check-textrel.out $(objpfx)check-execstack.out \ $(objpfx)check-wx-segment.out \ @@ -1907,3 +1908,16 @@ $(objpfx)list-tunables.out: tst-rtld-list-tunables.sh $(objpfx)ld.so $(evaluate-test) tst-dst-static-ENV = LD_LIBRARY_PATH='$$ORIGIN' + +$(objpfx)tst-rtld-help.out: $(objpfx)ld.so + $(test-wrapper) $(rtld-prefix) --help > $@; \ + status=$$?; \ + echo "info: ld.so exit status: $$status" >> $@; \ + if ! grep -q 'Legacy HWCAP subdirectories under library search path directories' $@; then \ + echo "error: missing subdirectory pattern" >> $@; \ + if test $$status -eq 0; then \ + status=1; \ + fi; \ + fi; \ + (exit $$status); \ + $(evaluate-test) diff --git a/elf/dl-load.c b/elf/dl-load.c index 376a2e64d6..2f760503c5 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -758,8 +758,14 @@ _dl_init_paths (const char *llp, const char *source, max_dirnamelen = SYSTEM_DIRS_MAX_LEN; *aelem = NULL; - /* This points to the map of the main object. */ + /* This points to the map of the main object. If there is no main + object (e.g., under --help, use the dynamic loader itself as a + stand-in. */ l = GL(dl_ns)[LM_ID_BASE]._ns_loaded; +#ifdef SHARED + if (l == NULL) + l = &GL (dl_rtld_map); +#endif assert (l->l_type != lt_loaded); if (l->l_info[DT_RUNPATH])