From patchwork Sat Oct 8 11:13:35 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?G=C3=BCnther_Noack?= X-Patchwork-Id: 13001755 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 7A87DC433FE for ; Sat, 8 Oct 2022 11:13:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229751AbiJHLNm (ORCPT ); Sat, 8 Oct 2022 07:13:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52206 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229655AbiJHLNl (ORCPT ); Sat, 8 Oct 2022 07:13:41 -0400 Received: from mail-ej1-x630.google.com (mail-ej1-x630.google.com [IPv6:2a00:1450:4864:20::630]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 64AE050F9C; Sat, 8 Oct 2022 04:13:40 -0700 (PDT) Received: by mail-ej1-x630.google.com with SMTP id sc25so9990408ejc.12; Sat, 08 Oct 2022 04:13:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=ihEjAwkgFK6TMTS0NNrc4Hr909XAXppfc/t74qtEVys=; b=f2HrepYiLnsiyurPsv8FfJmNKnyEObBrKn9ZmsuFKHTBOK7v+jCNGMfhikSi2o38S4 6trakx72A5xPrYPkw9+Xl8nsWzF77FHEJw4fN6G3YnlVnos93/TYRCHTedRXuVZZw++z yhwwqTJqtUv9FQw1BAzFfexJrsSIqZy+Vaqed9ycd+6s+lHom+6ZWuVRT7qHY84iZ2MT nIug5TWcZKX3iT1GQV71KUrADQ0hSAz2beQK6SEGI6O/Bzd0Ny574fjLd/wPLWskjhW3 9KhFeYaXUGid5gXXd6vqBVaImfj/FfA4CFRFWT9bwU97Z/CFUETYMuFa+RuavHJHV9IQ UaIg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=ihEjAwkgFK6TMTS0NNrc4Hr909XAXppfc/t74qtEVys=; b=b+MQwSJbomuPf5kl6ja7xKHhzbTbS/zFG0V2Q/1HNxGqeHU8UxDYaFTLf9L168MBLR R3qmLEszMNGVi/HBZB2gG9+h0I/REwaMrw2Eg0r8NNYqqd/TVASXnLDoxdY/xjuNmEEa PESCTQShiiCQk/bNKIMWaNNSrRNVReUv1pGYkfYDtzOyFPprV81quP+02XBwIUolhimw c6oZXB2QljN7GRYN5tzaiuWpCxmQ7xmGvWjTYmUL1HBT0hZ1blIjMJS04REQ66UZrQZq iXGa8k59JC+G5/XYQ9Xpc8Pd8+AMmNMQSArFPvf20UJt/QE26LLZUZlJZEc2HwSZd/It eWnA== X-Gm-Message-State: ACrzQf1paQdtxtyFRJh1k937nZtPnj5yVgogFXpL0qsO1wOO0yYpxqMG P3XTu1O11jfon0FPPmzo/3up1uTlY4A= X-Google-Smtp-Source: AMsMyM5FLfV/bK2bwe6T/on3YEKYaemvoo3hE1d8d+4VvD0Z4vGcWdt6BytOfV2Z/x8+kpsYt7nDDg== X-Received: by 2002:a17:907:e93:b0:78d:46ae:cf61 with SMTP id ho19-20020a1709070e9300b0078d46aecf61mr7343327ejc.579.1665227618860; Sat, 08 Oct 2022 04:13:38 -0700 (PDT) Received: from nuc.i.gnoack.org ([2a02:168:633b:1:1e69:7aff:fe05:97e6]) by smtp.gmail.com with ESMTPSA id kt25-20020a1709079d1900b0078d886c871bsm1740312ejc.70.2022.10.08.04.13.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 08 Oct 2022 04:13:38 -0700 (PDT) From: =?utf-8?q?G=C3=BCnther_Noack?= To: linux-security-module@vger.kernel.org Cc: =?utf-8?q?Micka=C3=ABl_Sala=C3=BCn?= , James Morris , Paul Moore , "Serge E . Hallyn" , linux-fsdevel@vger.kernel.org, Konstantin Meskhidze , Nathan Chancellor , =?utf-8?q?G=C3=BCnther_Noack?= Subject: [PATCH v9 10/11] samples/landlock: Extend sample tool to support LANDLOCK_ACCESS_FS_TRUNCATE Date: Sat, 8 Oct 2022 13:13:35 +0200 Message-Id: <20221008111336.74806-1-gnoack3000@gmail.com> X-Mailer: git-send-email 2.38.0 MIME-Version: 1.0 Precedence: bulk List-ID: Update the sandboxer sample to restrict truncate actions. This is automatically enabled by default if the running kernel supports LANDLOCK_ACCESS_FS_TRUNCATE, except for the paths listed in the LL_FS_RW environment variable. Signed-off-by: Günther Noack --- samples/landlock/sandboxer.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/samples/landlock/sandboxer.c b/samples/landlock/sandboxer.c index f29bb3c72230..fd4237c64fb2 100644 --- a/samples/landlock/sandboxer.c +++ b/samples/landlock/sandboxer.c @@ -76,7 +76,8 @@ static int parse_path(char *env_path, const char ***const path_list) #define ACCESS_FILE ( \ LANDLOCK_ACCESS_FS_EXECUTE | \ LANDLOCK_ACCESS_FS_WRITE_FILE | \ - LANDLOCK_ACCESS_FS_READ_FILE) + LANDLOCK_ACCESS_FS_READ_FILE | \ + LANDLOCK_ACCESS_FS_TRUNCATE) /* clang-format on */ @@ -160,11 +161,12 @@ static int populate_ruleset(const char *const env_var, const int ruleset_fd, LANDLOCK_ACCESS_FS_MAKE_FIFO | \ LANDLOCK_ACCESS_FS_MAKE_BLOCK | \ LANDLOCK_ACCESS_FS_MAKE_SYM | \ - LANDLOCK_ACCESS_FS_REFER) + LANDLOCK_ACCESS_FS_REFER | \ + LANDLOCK_ACCESS_FS_TRUNCATE) /* clang-format on */ -#define LANDLOCK_ABI_LAST 2 +#define LANDLOCK_ABI_LAST 3 int main(const int argc, char *const argv[], char *const *const envp) { @@ -234,6 +236,10 @@ int main(const int argc, char *const argv[], char *const *const envp) case 1: /* Removes LANDLOCK_ACCESS_FS_REFER for ABI < 2 */ ruleset_attr.handled_access_fs &= ~LANDLOCK_ACCESS_FS_REFER; + __attribute__((fallthrough)); + case 2: + /* Removes LANDLOCK_ACCESS_FS_TRUNCATE for ABI < 3 */ + ruleset_attr.handled_access_fs &= ~LANDLOCK_ACCESS_FS_TRUNCATE; fprintf(stderr, "Hint: You should update the running kernel "