From patchwork Thu Oct 17 09:17:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antonio Quartulli X-Patchwork-Id: 1998474 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=unstable.cc header.i=a@unstable.cc header.a=rsa-sha256 header.s=20220809-q8oc header.b=UT4mVmBx; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=2620:52:3:1:0:246e:9693:128c; helo=server2.sourceware.org; envelope-from=libc-alpha-bounces~incoming=patchwork.ozlabs.org@sourceware.org; receiver=patchwork.ozlabs.org) Received: from server2.sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4XTj1d0s5cz1xw7 for ; Thu, 17 Oct 2024 20:18:29 +1100 (AEDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 581CA3858C35 for ; Thu, 17 Oct 2024 09:18:27 +0000 (GMT) X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from wilbur.contactoffice.com (wilbur.contactoffice.com [212.3.242.68]) by sourceware.org (Postfix) with ESMTPS id 5B2943858D20 for ; Thu, 17 Oct 2024 09:17:59 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 5B2943858D20 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=unstable.cc Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=unstable.cc ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 5B2943858D20 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=212.3.242.68 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1729156689; cv=none; b=ThZPmUx1rRMbXnVFb/t4m2up0i4la5rc/dp+CL5LFaOSnuYzqA+xIz+7342BRrkFjUpdStVA4Rm+j/2uMX4PNspxowab8C9E5W1e1jQSPd8elm14qXatVrNU/qRUwkstK1et/76DfpgK2wZbKiiccSqvVlE+FYMgbglVDv/p/xs= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1729156689; c=relaxed/simple; bh=VtrWJ9mo5imtBwHo0UP9T7raEZdZ9UufhGNPSNnLkmw=; h=DKIM-Signature:From:To:Subject:Date:Message-ID:MIME-Version; b=xOxAiJaxbqLmOKQWMr2/2bh8uAi9IjJTUOckCjTuFd6t+z9DyITx0kZ5t6KClG1cZWEL5Wz1GO1o3oWVtVyqYKXjQ6cxiBYbqhlmwJDSPG6uaCq4PDnHVGhMpWrkH8cKkEzDUM+twkcUCVunsZZZBQgEyf9+vg81sVAoYyEx5Os= ARC-Authentication-Results: i=1; server2.sourceware.org Received: from smtpauth2.co-bxl (smtpauth2.co-bxl [10.2.0.24]) by wilbur.contactoffice.com (Postfix) with ESMTP id A7573133C; Thu, 17 Oct 2024 11:17:57 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1729156677; s=20220809-q8oc; d=unstable.cc; i=a@unstable.cc; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Transfer-Encoding; bh=NIsKATt8C8e1enwF+cf+uiVbvIaJGOZwApmJg5hRfi4=; b=UT4mVmBxp51gd6M00bvt73Kh3vnMzqEYM+0QVjUkudbTdaiSOiHs8q5yR5HqktgZ g4h9c2EaARKtOPqHAeZXVWYn0OSKuPvB4jBgvCLSKyCHstZ5IC1uCWqN6GDSEzM6iUg Rb9YiJmxYtO1ED9cKF4p1oevAbPvsNFWOqbgch27fRYffnsfqL00OMnJtIA9zGZPj73 Wg1q52Ry7v32Xx8ePdxu5JUPdAeaQoet4IPK0S1eGU7N+fA0Zt091LRVKHB9pbRloXL AlrNvHRSaYvc54V+Af3ba7wcEA7426+JogYig0z/sb66J3WAfhTHlKxxctirho/aOhg wL51NV8GjQ== Received: by smtp.mailfence.com with ESMTPSA ; Thu, 17 Oct 2024 11:17:50 +0200 (CEST) From: Antonio Quartulli To: libc-alpha@sourceware.org Cc: Antonio Quartulli , Arne Schwabe , Cristina Nita-Rotaru , Anqi Chen Subject: [PATCH v3] nss: reject invalid port passed to getaddrinfo [BZ #16208] Date: Thu, 17 Oct 2024 11:17:34 +0200 Message-ID: <20241017091734.2286-1-a@unstable.cc> X-Mailer: git-send-email 2.45.2 MIME-Version: 1.0 X-ContactOffice-Account: com:375058688 X-Spam-Status: No, score=-12.3 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_LOW, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libc-alpha-bounces~incoming=patchwork.ozlabs.org@sourceware.org When passing a numeric string as port/service to getaddrinfo() representing a number larger than 65535, the function will not complain and will simply extract the lowest 16bits of the converted number. Specifically, the string is converted to int by calling strtoul() and later it is moved to gaih_servtuple.num after passing through htons(). For example, invoking getaddrinfo() with service equal to "70000" will result in no error and ai_addr->sin_port set to 4464. This issue was (re)discovered by researcher Anqi Chen while stress testing OpenVPN with invalid config parameters. Thanks a lot to Arne Schwabe for finding out that the root cause was hidden inside glibc. Similarly, also when passing 0 or an out of range value, no error is thrown while it should. Add proper checks to reject invalid values immediately. The 'num' member has been converted to unsigned long in order to properly store the result of strtoul(). Then, while checking for 'num' being greater than USHRT_MAX, we also catch overflows/out-of-range values (strtoul() returns ULONG_MAX in that case). Cc: Arne Schwabe Cc: Cristina Nita-Rotaru Reported-by: Anqi Chen Signed-off-by: Antonio Quartulli --- Changes from v2: * allowed specifying 0 as port number (equivalent to not passing any port) * changed unit-test to check success when passing 0 as port --- nss/Makefile | 1 + nss/getaddrinfo.c | 16 ++++++++-- nss/tst-getaddrinfo6.c | 67 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 82 insertions(+), 2 deletions(-) create mode 100644 nss/tst-getaddrinfo6.c diff --git a/nss/Makefile b/nss/Makefile index 9331b3308c..94acfd0e38 100644 --- a/nss/Makefile +++ b/nss/Makefile @@ -321,6 +321,7 @@ tests := \ tst-getaddrinfo \ tst-getaddrinfo2 \ tst-getaddrinfo3 \ + tst-getaddrinfo6 \ tst-gethnm \ tst-getpw \ tst-gshadow \ diff --git a/nss/getaddrinfo.c b/nss/getaddrinfo.c index 3ccd3905fa..32c2672aaa 100644 --- a/nss/getaddrinfo.c +++ b/nss/getaddrinfo.c @@ -95,7 +95,7 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. struct gaih_service { const char *name; - int num; + unsigned long num; }; struct gaih_servtuple @@ -2375,7 +2375,19 @@ getaddrinfo (const char *name, const char *service, return EAI_NONAME; } - gaih_service.num = -1; + /* 0 means "no numeric port provided" (which is equivalent to + passing 0 as port) */ + gaih_service.num = 0; + } + /* port number must be in range [0, USHRT_MAX]. + Any other value is invalid. + strtoul returns ULONG_MAX in case of out-of-range + input and it is caught by this check */ + else if (gaih_service.num > USHRT_MAX) + { + /* provided numeric string is invalid */ + __free_in6ai (in6ai); + return EAI_NONAME; } pservice = &gaih_service; diff --git a/nss/tst-getaddrinfo6.c b/nss/tst-getaddrinfo6.c new file mode 100644 index 0000000000..c237315fd0 --- /dev/null +++ b/nss/tst-getaddrinfo6.c @@ -0,0 +1,67 @@ +/* Test invalid port/service lookup [BZ #16208]. + Copyright (C) 2014-2024 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 +#include +#include + +static int +do_one_test (const char *service, int expected_err) +{ + const int family[2] = { AF_INET, AF_INET6 }; + struct addrinfo hints, *aitop; + int index, gaierr; + int result = 0; + + for (index = 0; index < sizeof (family) / sizeof (family[0]); ++index) + { + memset (&hints, '\0', sizeof (hints)); + hints.ai_family = family[index]; + + gaierr = getaddrinfo (NULL, service, &hints, &aitop); + if (gaierr != expected_err) + { + printf ("FAIL getaddrinfo returned %d, should return %d\n", + gaierr, expected_err); + result = 1; + } + } + + return result; +} + + +static int +do_test (void) +{ + int err = 0; + + err |= do_one_test ("0", 0); // should succeed + err |= do_one_test ("70000", EAI_NONAME); + err |= do_one_test ("-1", EAI_NONAME); + err |= do_one_test ("18446744073709551616", EAI_NONAME); + err |= do_one_test ("-18446744073709551616", EAI_NONAME); + + return err; +} +#define TEST_FUNCTION do_test () + +#include "../test-skeleton.c"