From patchwork Fri Jul 8 04:48:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gow X-Patchwork-Id: 12910574 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 8932DC43334 for ; Fri, 8 Jul 2022 04:49:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237019AbiGHEtY (ORCPT ); Fri, 8 Jul 2022 00:49:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51398 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237356AbiGHEtN (ORCPT ); Fri, 8 Jul 2022 00:49:13 -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 5330A76974 for ; Thu, 7 Jul 2022 21:49:12 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-31c95f27403so92821527b3.6 for ; Thu, 07 Jul 2022 21:49:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=UquCbMkMEN53oDqhrIsDuW+/Yi+lnpJDBsKu7NltgmI=; b=SPGqZ7snq0dDaZavBhTshBo3GD/RIz16PYHpkAZP09NkIM7rSc3+bp+s6l/7++Cv7B XWa5GQMin+l++ZOP/yB/e+b60YfCQdDYXY2VcElGWwTBkz3vCLMTOOcnR9cOfsiNGmj8 tlqh1FLXZ3uERR/doIcBKL6AyyV2xy+uFI/GmTVeOB6R3o2WyolQeIvTIgXgI3a+UUqv c5paBcyBylaDfDM1yzvksVPzvjik6pRI4mF17AwFW08HuS2JXclpRWj3VnAvBFZNo7Ea 6QdKwSftZV1L52yNE7NANxbkca+Rdd+HxSkS2rq66Tt7UH0+HZ+lXRb32QqGn/pRABWO nFwg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=UquCbMkMEN53oDqhrIsDuW+/Yi+lnpJDBsKu7NltgmI=; b=yvYEatLOgFtqamksqia7haWHKgAlny7+frfzzicpZShajBB24Z9+vvUZqn8g6MgAnw EjCgRKCMp14fNZAC64q45hKgiMtCJ5v0frB4RMQ1ccjU4cfwNfq9THW1VEECu3DCHVAA aXQlC4aHM8C9TPOJ6KIXGSqP9ULTJAKPETJs99kVV5Lzuw0glQSyQ8odVq1T/5vVTjSQ ftrUXCZ8BiAg65IN9jtkPLn3V3+C1j6ukZ7nzI3f7FBTy5ancdDzTrkIWPmBIINtGNjN eHhCGW3ImBHTpWyDHFEPqCpGMpizy9MpFjkUVpUMbxv/gom7qHFwZiKct5Zww4BLefSl OJiQ== X-Gm-Message-State: AJIora8WO6992/+dBY6KvsHRp0KdHyoJpMMf8IQVewtOmouExIBL16oV zPCCTLAuGufoa1J0VFra5Su06Av45vHDcg== X-Google-Smtp-Source: AGRyM1s34hRTvZB8Y7Xk9te1i17z6IbWppPGWTLYgGaU9rmBgS1u+VkLNYZr0Wk1pk93+iVd+YYx2UmXUKNKpA== X-Received: from slicestar.c.googlers.com ([fda3:e722:ac3:cc00:4f:4b78:c0a8:20a1]) (user=davidgow job=sendgmr) by 2002:a25:ad14:0:b0:66e:cb9e:8d43 with SMTP id y20-20020a25ad14000000b0066ecb9e8d43mr1664970ybi.176.1657255751621; Thu, 07 Jul 2022 21:49:11 -0700 (PDT) Date: Fri, 8 Jul 2022 12:48:45 +0800 In-Reply-To: <20220708044847.531566-1-davidgow@google.com> Message-Id: <20220708044847.531566-2-davidgow@google.com> Mime-Version: 1.0 References: <20220708044847.531566-1-davidgow@google.com> X-Mailer: git-send-email 2.37.0.rc0.161.g10f37bed90-goog Subject: [PATCH v6 2/4] module: panic: Taint the kernel when selftest modules load From: David Gow To: Brendan Higgins , Andy Shevchenko , Jonathan Corbet , Andrew Morton , Kees Cook , Shuah Khan , Greg KH , Luis Chamberlain , Masahiro Yamada , Nathan Chancellor Cc: David Gow , "Guilherme G . Piccoli" , Sebastian Reichel , John Ogness , Joe Fradley , Daniel Latypov , kunit-dev@googlegroups.com, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Jani Nikula , Lucas De Marchi , Aaron Tomlin , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, Michal Marek , Nick Desaulniers , linux-kbuild@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Taint the kernel with TAINT_TEST whenever a test module loads, by adding a new "TEST" module property, and setting it for all modules in the tools/testing directory. This property can also be set manually, for tests which live outside the tools/testing directory with: MODULE_INFO(test, "Y"); Reviewed-by: Luis Chamberlain Reviewed-by: Aaron Tomlin Acked-by: Brendan Higgins Signed-off-by: David Gow --- Version 6 of this patch fixes the issue pointed out by Nathan here, whereby the check for the module property was inverted: https://lore.kernel.org/linux-kselftest/Ysd9FG1fOSnzKv8d@dev-arch.thelio-3990X/ Changes since v5: https://lore.kernel.org/linux-kselftest/20220702040959.3232874-2-davidgow@google.com/ - Fix the test for the module property being inverted, making this patch do exactly the opposite of what it should. (Thanks Nathan Chancellor) - Revert to using pr_warn(), as we already don't warn if the kernel is tainted, so won't spam the logs. - Add Reviewed-, Acked-by tags. Changes since v4: https://lore.kernel.org/linux-kselftest/20220701084744.3002019-2-davidgow@google.com/ - Use pr_warn_once() to only log a warning the first time a module taints the kernel with TAINT_TEST - Loading lots of test modules is a common usecase, and this would otherwise spam the logs too much. - Thanks Luis. - Remove a superfluous newline (Thanks Greg) - Add Luis' Reviewed-by tag. This patch was new in v4 of the series. --- kernel/module/main.c | 7 +++++++ scripts/mod/modpost.c | 3 +++ 2 files changed, 10 insertions(+) diff --git a/kernel/module/main.c b/kernel/module/main.c index fed58d30725d..4723f1316709 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -1988,6 +1988,13 @@ static int check_modinfo(struct module *mod, struct load_info *info, int flags) /* Set up license info based on the info section */ set_license(mod, get_modinfo(info, "license")); + if (get_modinfo(info, "test")) { + if (!test_taint(TAINT_TEST)) + pr_warn("%s: loading test module taints kernel.\n", + mod->name); + add_taint_module(mod, TAINT_TEST, LOCKDEP_STILL_OK); + } + return 0; } diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 29d5a841e215..5937212b4433 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -2191,6 +2191,9 @@ static void add_header(struct buffer *b, struct module *mod) if (strstarts(mod->name, "drivers/staging")) buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); + + if (strstarts(mod->name, "tools/testing")) + buf_printf(b, "\nMODULE_INFO(test, \"Y\");\n"); } static void add_exported_symbols(struct buffer *buf, struct module *mod)