From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yb1-xb34.google.com (mail-yb1-xb34.google.com [IPv6:2607:f8b0:4864:20::b34]) by sourceware.org (Postfix) with ESMTPS id 14B973858C54 for ; Fri, 12 Jan 2024 13:54:01 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 14B973858C54 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 14B973858C54 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=2607:f8b0:4864:20::b34 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1705067644; cv=none; b=Gw85gjmeqoHSvZiXzCqgPqI0heuTXT/uHyBU1aRu8hNth0Ay7KIQg85EEWZOiYHsc3mnZ4DGur3WMG7Pb6zKRr/r2kih/vJfBYYP+1Ms/VdwLmUNjMOp2Yd/dWOFc6Zi2sXZh4GbX0vKeE7qrlUVPs/+X48p7Tgp0S55M+ZtFcQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1705067644; c=relaxed/simple; bh=nltNA5wDcIxvDsdqbOyKd/vL3/tG0onGETKOPEMWRZk=; h=DKIM-Signature:MIME-Version:From:Date:Message-ID:Subject:To; b=wbXjsshqG4PQAJoRMa3QF/xt+WLTu05DyzG7v7ti5GrnWENfdAL04rLHFVsNUB2ONwIByUufpOMM1pHpNjKfbled3inLC/emLIBbwornIzUYxH8Wh9EO835VaSQqSj0BS6ONuMJfwnu/hX3p3Mi+OmFhYvbIrSN9rVuBzHF1nDE= ARC-Authentication-Results: i=1; server2.sourceware.org Received: by mail-yb1-xb34.google.com with SMTP id 3f1490d57ef6-db3fa47c2f7so5670552276.0 for ; Fri, 12 Jan 2024 05:54:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1705067640; x=1705672440; darn=sourceware.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=lcvAGrJnTDb0tf0s4vbjI5nYhLL4D1rJeUs+ue3zfDM=; b=Ift3RGeyLduJgogaerxTG2skqJirNJt1zWeImZO89iHBOeNzkJvyT1yH7ibkiBf6mO /j2b2BVkEI7j2WlqWqbuuNzPWOyOcujFw3z644LK4vZwVjdFjJto5Aoc0yKQVopxLkMy fUjGvqCXxVPovx/lHYlmaTDUvgJ99DS9Q2PvaUcmIH7ZGn3zljd9wMwfHJd9Q3jkCqWn vtraizaOEqJ+/8k1LypTSlbcpQMJ5EfcEj67u2nwiXCLORNdHkSyBCrPW/5VLqzPOvE/ 3Pd03a9MFBiuTVrncliUjv53lYLlcc7rUyAOel1xRZ/EBTVAQatagI19ZLXwrAmw6isG qBNQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705067640; x=1705672440; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=lcvAGrJnTDb0tf0s4vbjI5nYhLL4D1rJeUs+ue3zfDM=; b=QOrZfCHW+6Q9mhpKEekxMxt4xT7HxidgVfBRxcycTr/qvbp8mLo/3IN9urtNPk8zGR ly5WihQHY4FsVFLSojo8U40ev7B3LVNA6RhLpNjySI3FCAXmUe76e6QASI+acyUgvs6h eLKMhNcWmKtYBVc4IpE6vsAVlqa6G90iatCstTFYkTr4w09Hp1FsW8TIenKXnFaPoE1C /dGJUv1d2ZRVeMRFnN8UWE5NJ+b3+pmqEEXz2efwroq/lYmFQG4fDw43H8epweR3PJt1 ALAlw5G7NGl+WzGWxKa9ZcecL0YUILFZEH5QLlTTF8ODDK7nE6lS6Az6j86+AD4DR4Am o3Ug== X-Gm-Message-State: AOJu0YxMOpQqKy3JpkEVcIbK8gvNogZvE6eaySf2s+Zf+Daasb2qxVQC 9wEna6p60mjx01YvP2BOKAiOkK8wJ1vyyrp1FiQ= X-Google-Smtp-Source: AGHT+IHuP9T6Ot7kGTPSH7Ygm9GPHygFGaaIxRx9WbmcRve+AKfF8cjATzp1HQ2Y/j/1w4gTRO5tjHoY+yrUgzFaXCo= X-Received: by 2002:a05:6902:2409:b0:dbd:c9f5:80f9 with SMTP id dr9-20020a056902240900b00dbdc9f580f9mr621095ybb.32.1705067640243; Fri, 12 Jan 2024 05:54:00 -0800 (PST) MIME-Version: 1.0 References: <20240112134328.568424-1-josimmon@redhat.com> In-Reply-To: <20240112134328.568424-1-josimmon@redhat.com> From: "H.J. Lu" Date: Fri, 12 Jan 2024 05:53:23 -0800 Message-ID: Subject: Re: [PATCH v4] rtld: Add glibc.rtld.enable_secure tunable. To: Joe Simmons-Talbott Cc: libc-alpha@sourceware.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-3021.1 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,GIT_PATCH_0,KAM_SHORT,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,TXREP,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Fri, Jan 12, 2024 at 5:44=E2=80=AFAM Joe Simmons-Talbott wrote: > > Add a tunable for setting __libc_enable_secure to 1. Do not set > __libc_enable_secure to 0 if the tunable is set to 0. Ignore all > tunables if glib.rtld.enable_secure is set. One use-case for this > addition is to enable testing code paths that depend on > __libc_enable_secure being set without the need to use setxid binaries. > --- > Changes to v3: > * Rebase and fix merge conflict in NEWS. > > Changes to v2: > * handle the tunable in __tunables_init so that it's done in a single > place. > * ignore all tunables if the tunable is set. > * update the testcase to only check the tunables if the enable_secure > tunable is not set. > * don't add tunables_strcmp as there is now already a version. > > Changes to v1: > * handle the tunable for the dynamic loader as well. > > NEWS | 5 ++ > elf/Makefile | 2 + > elf/dl-tunables.c | 11 +++ > elf/dl-tunables.list | 6 ++ > elf/tst-rtld-list-tunables.exp | 1 + > elf/tst-tunables-enable_secure.c | 126 +++++++++++++++++++++++++++++++ > 6 files changed, 151 insertions(+) > create mode 100644 elf/tst-tunables-enable_secure.c > > diff --git a/NEWS b/NEWS > index 83ae627f47..aff44f6d7f 100644 > --- a/NEWS > +++ b/NEWS > @@ -55,6 +55,11 @@ Major new features: > unsigned char, unsigned short, unsigned int, unsigned long int and > unsigned long long int, and a type-generic macro. > > +* A new tunable, glibc.rtld.enable_secure, used to run a program > + as if it were a setuid process, enabling a number of security features= . This > + is currently a testing tool to allow more extensive verification tests= for > + AT_SECURE programs and not meant to be a security feature. > + > Deprecated and removed features, and other changes affecting compatibili= ty: > > * The ldconfig program now skips file names containing ';' or ending in > diff --git a/elf/Makefile b/elf/Makefile > index 5d78b659ce..45a6aa7a8d 100644 > --- a/elf/Makefile > +++ b/elf/Makefile > @@ -285,6 +285,7 @@ tests-static-internal :=3D \ > tst-tls1-static \ > tst-tls1-static-non-pie \ > tst-tunables \ > + tst-tunables-enable_secure \ > # tests-static-internal > > CRT-tst-tls1-static-non-pie :=3D $(csu-objpfx)crt1.o > @@ -2676,6 +2677,7 @@ $(objpfx)tst-glibc-hwcaps-mask.out: \ > $(objpfx)tst-glibc-hwcaps-cache.out: $(objpfx)tst-glibc-hwcaps > > tst-tunables-ARGS =3D -- $(host-test-program-cmd) > +tst-tunables-enable_secure-ARGS =3D -- $(host-test-program-cmd) > > $(objpfx)list-tunables.out: tst-rtld-list-tunables.sh $(objpfx)ld.so > $(SHELL) $< $(objpfx)ld.so '$(test-wrapper-env)' \ > diff --git a/elf/dl-tunables.c b/elf/dl-tunables.c > index 03e1a68675..d3ccd2ecd4 100644 > --- a/elf/dl-tunables.c > +++ b/elf/dl-tunables.c > @@ -223,6 +223,17 @@ parse_tunables_string (const char *valstring, struct= tunable_toset_t *tunables) > { > tunables[ntunables++] =3D > (struct tunable_toset_t) { cur, value, p - value }; > + > + /* Ignore tunables if enable_secure is set */ > + if (tunable_is_name ("glibc.rtld.enable_secure", name)) > + { > + tunable_num_t val =3D (tunable_num_t) _dl_strtoul (val= ue, NULL); > + if (val =3D=3D 1) > + { > + __libc_enable_secure =3D 1; > + return 0; > + } > + } > break; > } > } > diff --git a/elf/dl-tunables.list b/elf/dl-tunables.list > index 1b40407814..1186272c81 100644 > --- a/elf/dl-tunables.list > +++ b/elf/dl-tunables.list > @@ -136,6 +136,12 @@ glibc { > minval: 0 > default: 512 > } > + enable_secure { > + type: INT_32 > + minval: 0 > + maxval: 1 > + default: 0 > + } > } > > mem { > diff --git a/elf/tst-rtld-list-tunables.exp b/elf/tst-rtld-list-tunables.= exp > index 2233ea9c7c..db0e1c86e9 100644 > --- a/elf/tst-rtld-list-tunables.exp > +++ b/elf/tst-rtld-list-tunables.exp > @@ -12,5 +12,6 @@ glibc.malloc.tcache_unsorted_limit: 0x0 (min: 0x0, max:= 0x[f]+) > glibc.malloc.top_pad: 0x20000 (min: 0x0, max: 0x[f]+) > glibc.malloc.trim_threshold: 0x0 (min: 0x0, max: 0x[f]+) > glibc.rtld.dynamic_sort: 2 (min: 1, max: 2) > +glibc.rtld.enable_secure: 0 (min: 0, max: 1) > glibc.rtld.nns: 0x4 (min: 0x1, max: 0x10) > glibc.rtld.optional_static_tls: 0x200 (min: 0x0, max: 0x[f]+) > diff --git a/elf/tst-tunables-enable_secure.c b/elf/tst-tunables-enable_s= ecure.c > new file mode 100644 > index 0000000000..790d14237e > --- /dev/null > +++ b/elf/tst-tunables-enable_secure.c > @@ -0,0 +1,126 @@ > +/* Check GLIBC_TUNABLES parsing for enable_secure. > + Copyright (C) 2023 Free Software Foundation, Inc. 2024 > + 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 > +#include > +#include > +#include > +#include > +#include > +#include > + > +static int restart; > +#define CMDLINE_OPTIONS \ > + { "restart", no_argument, &restart, 1 }, > + > +static const struct test_t > +{ > + const char *env; > + int32_t expected_malloc_check; > + int32_t expected_enable_secure; > +} tests[] =3D > +{ > + /* Expected tunable format. */ > + /* Tunables should be ignored if enable_secure is set. */ > + { > + "glibc.malloc.check=3D2:glibc.rtld.enable_secure=3D1", > + 0, > + 1, > + }, > + /* Tunables should be ignored if enable_secure is set. */ > + { > + "glibc.rtld.enable_secure=3D1:glibc.malloc.check=3D2", > + 0, > + 1, > + }, > + /* Tunables should be set if enable_secure is unset. */ > + { > + "glibc.rtld.enable_secure=3D0:glibc.malloc.check=3D2", > + 2, > + 0, > + }, > +}; > + > +static int > +handle_restart (int i) > +{ > + if (tests[i].expected_enable_secure =3D=3D 1) > + { > + TEST_COMPARE (1, __libc_enable_secure); > + } > + else > + { > + TEST_COMPARE (tests[i].expected_malloc_check, > + TUNABLE_GET_FULL (glibc, malloc, check, int32_t, NULL= )); > + TEST_COMPARE (tests[i].expected_enable_secure, > + TUNABLE_GET_FULL (glibc, rtld, enable_secure, int32_t= , > + NULL)); > + } > + return 0; > +} > + > +static int > +do_test (int argc, char *argv[]) > +{ > + /* We must have either: > + - One or four parameters left if called initially: > + + path to ld.so optional > + + "--library-path" optional > + + the library path optional > + + the application name > + + the test to check */ > + > + TEST_VERIFY_EXIT (argc =3D=3D 2 || argc =3D=3D 5); > + > + if (restart) > + return handle_restart (atoi (argv[1])); > + > + char nteststr[INT_BUFSIZE_BOUND (int)]; > + > + char *spargv[10]; > + { > + int i =3D 0; > + for (; i < argc - 1; i++) > + spargv[i] =3D argv[i + 1]; > + spargv[i++] =3D (char *) "--direct"; > + spargv[i++] =3D (char *) "--restart"; > + spargv[i++] =3D nteststr; > + spargv[i] =3D NULL; > + } > + > + for (int i =3D 0; i < array_length (tests); i++) > + { > + snprintf (nteststr, sizeof nteststr, "%d", i); > + > + printf ("[%d] Spawned test for %s\n", i, tests[i].env); > + setenv ("GLIBC_TUNABLES", tests[i].env, 1); > + struct support_capture_subprocess result > + =3D support_capture_subprogram (spargv[0], spargv); > + support_capture_subprocess_check (&result, "tst-tunables-enable_se= cure", > + 0, sc_allow_stderr); > + support_capture_subprocess_free (&result); > + } > + > + return 0; > +} > + > +#define TEST_FUNCTION_ARGV do_test > +#include > -- > 2.41.0 > --=20 H.J.