From patchwork Wed Aug 9 01:06:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Justin Stitt X-Patchwork-Id: 13347286 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 6FD81C04A94 for ; Wed, 9 Aug 2023 01:07:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231493AbjHIBHz (ORCPT ); Tue, 8 Aug 2023 21:07:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32854 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231499AbjHIBHx (ORCPT ); Tue, 8 Aug 2023 21:07:53 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5D0EE1BFB for ; Tue, 8 Aug 2023 18:07:47 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id 3f1490d57ef6-d47a02fc63fso4863728276.0 for ; Tue, 08 Aug 2023 18:07:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1691543266; x=1692148066; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=MG9K9YUhTMTzK19uCHNnSBLcKhcXx1YxnQhkeYxtQnQ=; b=FLufdnQLID7CLFxDuinWTCHCNOM0tHWDzh/Q+ezwYBHvUhcKrvNRwf2X/858fNR7wb d8vbxPP43ceY/pyaj0Uw5PQ59JrcnSpcF/a3LfcIMqUOkY5p5Iam1144VCB1Ons2vj81 BmLiwO5IZchhdKNB3Hp+SHWii5wcBQkoVNE1bp5inoSeur+njvbFP1qGHTgPtXq1kfjg BEkjKbj13r7baEfK+6B3OTRz0y7Eybl5D1FWifL02RvN4LssSj5E1eUpHkMefprJM5KT H0ueJcMX3S8gV9suDKG8GXE43UgliTiV3eYQCRxb8WAldQnhoOh0RconuamFRyja+cUu eP6Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691543266; x=1692148066; 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=MG9K9YUhTMTzK19uCHNnSBLcKhcXx1YxnQhkeYxtQnQ=; b=CNEZNa0BLQ9JH2UjclDcA+zirFQXYUIFSKKADm+tds7EX3KBpxmVrxas3TRx6WR1EH lR5PFYM9kq8OcIlUmwuyU+47NEw58pSTK+pFdnoQ3y7fouTlfRJUd+DdIkR14XZRHMfh 9Hv8NmJmZncJBJTnIPnnJLwAvJCiaFlbjwzCCgxKgU2tf4DZjAnH1Ca1d7+rgTUxpsOs YzUy0c+a0rGmVwA3yYCVi5lAj0rRoW21U6R7gDUnpgVWbXtBeP0EJ2mpMTEZR2GONqoe 7XmP3uxdLyiyxPq4fu0hgyUpGfwT9dzksHGKkO8I0bTubEO38rtCG9QPlPgb428OPiY6 wZfA== X-Gm-Message-State: AOJu0YwQ8Tw23Iwfa++2B9pkoIgX8s6Lduamq3omE8i2cNdZwI5NFhsH aDZq2VG4fZpgQ8LzpRS/h7SeOWDsEwM3inSIMQ== X-Google-Smtp-Source: AGHT+IHZpwGDo8C14lufhH346u2Bau1BUWvvndGq88fm59ryfmewZSsy7jAPCKUfUcYrjFtU1dpqY0m+aY5jSzBV5Q== X-Received: from jstitt-linux1.c.googlers.com ([fda3:e722:ac3:cc00:2b:ff92:c0a8:23b5]) (user=justinstitt job=sendgmr) by 2002:a25:ad26:0:b0:d58:6cea:84de with SMTP id y38-20020a25ad26000000b00d586cea84demr24517ybi.11.1691543266633; Tue, 08 Aug 2023 18:07:46 -0700 (PDT) Date: Wed, 09 Aug 2023 01:06:10 +0000 In-Reply-To: <20230809-net-netfilter-v2-0-5847d707ec0a@google.com> Mime-Version: 1.0 References: <20230809-net-netfilter-v2-0-5847d707ec0a@google.com> X-Developer-Key: i=justinstitt@google.com; a=ed25519; pk=tC3hNkJQTpNX/gLKxTNQKDmiQl6QjBNCGKJINqAdJsE= X-Developer-Signature: v=1; a=ed25519-sha256; t=1691543258; l=1182; i=justinstitt@google.com; s=20230717; h=from:subject:message-id; bh=PvqWKqnPHt6FvPDmHzVp42icOwjac4OjqNFq/tqlT4Q=; b=sh9zj/YLC302K92KXYEsgv5KQ7slHtAn4AjmXQutkadONIDR1z3dS2tfhEUE1/fEjCLLxhXmz uQNQ/ErDWgqDBqL2ooZ4J+hnTeNjcylCNu2Z3wgVuRaaaBWLe9vWLDa X-Mailer: b4 0.12.3 Message-ID: <20230809-net-netfilter-v2-7-5847d707ec0a@google.com> Subject: [PATCH v2 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_pad` as it's a more robust interface whilst maintaing zero-padding behavior. 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..5d1fb7018dba 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_pad(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; \