From patchwork Tue Aug 8 22:48:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Justin Stitt X-Patchwork-Id: 13347141 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3848BC05051 for ; Tue, 8 Aug 2023 22:48:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231524AbjHHWso (ORCPT ); Tue, 8 Aug 2023 18:48:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36866 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231542AbjHHWsm (ORCPT ); Tue, 8 Aug 2023 18:48:42 -0400 Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 942911B6 for ; Tue, 8 Aug 2023 15:48:41 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-5840614b13cso6940027b3.0 for ; Tue, 08 Aug 2023 15:48:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1691534921; x=1692139721; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=G9OF2QFsiP3MkrzN4gKJO5o0WhLZ6LzcN9E8K6dc8dQ=; b=Tk5sym5cRDFSry8K+vc1HytKkY3IbV6iZulQcdqzajiE0IVk3xAlVvRndUZmAf1bym qmBA/CUFS/PGUXiFjGhkccdVwoX3zHUdcOMoLvXMMUMjR8yufvUM3BMxdbZVUZUBohHJ XDd0dKfCAqHUdAGRMbnyrr4FGDyVDAC1FubuFJd7iCMUjnLDpsu9n3DTiB9Phq8Qvf0E q8U2keEGG0MEUAozFw72uG4Zvu2LbBhukIi5JUVz+Vr+B72eM5IBoS4QlmZ4vDb1Wq63 DfyTE1Qq1a9iFWqR253R9wuYjfP9rEWY7oXwiicHyPCLs7WfdwbOq9mI2Yx1daOUKLxs Jqyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691534921; x=1692139721; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=G9OF2QFsiP3MkrzN4gKJO5o0WhLZ6LzcN9E8K6dc8dQ=; b=FS+htgdxHOvuTROwBYnzOWqnnSn1Jgm0lwOyjkHRt5QglcRjRiPjZBqhGYPRA0iM9i Pm8s6kveBQHubE4b8apz6WiPocGnpdio/80UTm3hT3FJg4fIxxepE574jY+A8+HIEqR8 CXZ9EH7QsRt94gUdTdeGgDCFdN8i8S9ebDAO4RQMKLJt8oNoKvMP/xSR6UkZjmULUXEz a9Oh1OvQ61wfmZvkmHLmCs5rcdtU4Qi8CEXsODRm+900dlUzSzH0BZzaPwMwa/B3xLNt 48zJ2nxs9M9PpijHzAJDMwEgPPLTpacbqvuPtKF1fBJjK/0VnHQqKFmTKpko04KjmZjc r7Iw== X-Gm-Message-State: AOJu0YyZAPohmotRibo8soDo/6aircZhV3/kxNywlbwfhWGXFBZfKWAI OuoSHhlhSw3BrG32PiVWTH1je//c3QRaWk6BnQ== X-Google-Smtp-Source: AGHT+IGCyJW7+H01CcBpmwMLWO4IJOM2JRZefUJenQ9SapEIQSusWKx57m2Q2rpVYsPLUriKIRjxQtAgRFf96MgkCg== X-Received: from jstitt-linux1.c.googlers.com ([fda3:e722:ac3:cc00:2b:ff92:c0a8:23b5]) (user=justinstitt job=sendgmr) by 2002:a81:b61a:0:b0:586:e91a:46c2 with SMTP id u26-20020a81b61a000000b00586e91a46c2mr107296ywh.4.1691534920928; Tue, 08 Aug 2023 15:48:40 -0700 (PDT) Date: Tue, 08 Aug 2023 22:48:12 +0000 In-Reply-To: <20230808-net-netfilter-v1-0-efbbe4ec60af@google.com> Mime-Version: 1.0 References: <20230808-net-netfilter-v1-0-efbbe4ec60af@google.com> X-Developer-Key: i=justinstitt@google.com; a=ed25519; pk=tC3hNkJQTpNX/gLKxTNQKDmiQl6QjBNCGKJINqAdJsE= X-Developer-Signature: v=1; a=ed25519-sha256; t=1691534912; l=1134; i=justinstitt@google.com; s=20230717; h=from:subject:message-id; bh=Bp+w2rTLNgdzNlxLi9FLD4utZ4QUqpPxaPIds7U/AGY=; b=odK4V1dqN6Y308K04MH8d/MRrkeaDSd1rELzLfU+7SDbRdFBl0nXUSsw+H9Y12YsVkVDC43lj zmYSndS5Js/Dv3+IClsSCDsbs7OJ2vOQ6onFe43X7Ff2wDY/LO6DwG0 X-Mailer: b4 0.12.3 Message-ID: <20230808-net-netfilter-v1-7-efbbe4ec60af@google.com> Subject: [PATCH 7/7] netfilter: xtables: refactor deprecated strncpy From: Justin Stitt To: Pablo Neira Ayuso , Jozsef Kadlecsik , Florian Westphal , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: linux-hardening@vger.kernel.org, Kees Cook , netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Justin Stitt Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org Prefer `strscpy` as it's a more robust interface. There may have existed a bug here due to both `tbl->repl.name` and `info->name` having a size of 32 as defined below: | #define XT_TABLE_MAXNAMELEN 32 This may lead to buffer overreads in some situations -- `strscpy` solves this by guaranteeing NUL-termination of the dest buffer. Signed-off-by: Justin Stitt --- Note: build tested only --- net/netfilter/xt_repldata.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netfilter/xt_repldata.h b/net/netfilter/xt_repldata.h index 68ccbe50bb1e..63869fd0ec57 100644 --- a/net/netfilter/xt_repldata.h +++ b/net/netfilter/xt_repldata.h @@ -29,7 +29,7 @@ if (tbl == NULL) \ return NULL; \ term = (struct type##_error *)&(((char *)tbl)[term_offset]); \ - strncpy(tbl->repl.name, info->name, sizeof(tbl->repl.name)); \ + strscpy(tbl->repl.name, info->name, sizeof(tbl->repl.name)); \ *term = (struct type##_error)typ2##_ERROR_INIT; \ tbl->repl.valid_hooks = hook_mask; \ tbl->repl.num_entries = nhooks + 1; \