From patchwork Fri May 13 20:21:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12849368 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 16565C4332F for ; Fri, 13 May 2022 20:23:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1384127AbiEMUW7 (ORCPT ); Fri, 13 May 2022 16:22:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1384221AbiEMUWq (ORCPT ); Fri, 13 May 2022 16:22:46 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 225CC17569F for ; Fri, 13 May 2022 13:22:33 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id w21-20020a25df15000000b0064b401428bfso7256613ybg.22 for ; Fri, 13 May 2022 13:22:33 -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=A+7QPiSqoa8uHCAaz7cWSuhzWOaNl1zZwhVwOmSdW3Q=; b=eoneec1qCPJ+mzeLTO/26o4Gge0cWT5SAiGzbalPj2kajo6F/0cY+hXNaJV6/r+1ew Y6uGiwZLXUyodzZ8UYO/n8YLOsl89RGDclgPhS6fxgoPf/o7am8+mqu4bw/b3L+/Yuyi Cc/OaxzJLjKECCzrQRpdRnOuumBxE4idnbmxYj0GGrcjayFmVVo2gRU+pSIAIGWkmF0a 3GrUoXzWAOrstvsKGj3Hh/ia4A/Gbuk8XwS8MbQH/z19h/yMUcGvuCm84jFLSCi6XCzG qcVtZMwaKqUWyqXG9PrxZtGErnPUmFAsNBu4fvRjKv6v93XufMYo0X2ugGmnuiRsSDsp gASQ== 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=A+7QPiSqoa8uHCAaz7cWSuhzWOaNl1zZwhVwOmSdW3Q=; b=oQKgyZdxgYT2K15+DzOeBk3dzvimrSG3m6dmehTSFLnUmTZvC1SPFw+x1gkGEmzagL B+QyHfrA9bYDmnFU75NJAefbChHtkdVGFlbivNX8yKluAfRS7LIRWVPqw1ktjSaPYKl1 +2ZmiBHGgQebqsXj2dYO+c20ynlJI8vegUp+JitG95b2PNFl2bWU7qKgxs6+ux+61ap2 oPfECX6uvETc62LFcIACiKTm0ZVOo1Du5Mmk9szobmHavlN0k7+LzKo4Dczfs14G8Hei vBPMXONTTdzLncPgIj5m7cpsvhwAdPw0I0C6kXV0wYUFTKbwZmKK6L117aOsV0IPjWjn CO+g== X-Gm-Message-State: AOAM5320qi9xvjg1H6L8J11B7WdRlkaQso+5wc+gPoGXFpdbwNGHvqUe zNM23c4NAg3Obi2mw1zL+YNboLFQfyEN8b8Hcxo= X-Google-Smtp-Source: ABdhPJzvGknJQJvJIOdsshYzjyQxItMWAOO5KzitzyEuNvSreyd+VCQrAAW9GnGKTwHoKx86rGgma5rzRyc5taV0BnQ= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:e0:c17e:c2dc:13eb]) (user=samitolvanen job=sendgmr) by 2002:a81:3685:0:b0:2fb:947b:5247 with SMTP id d127-20020a813685000000b002fb947b5247mr7593917ywa.64.1652473352269; Fri, 13 May 2022 13:22:32 -0700 (PDT) Date: Fri, 13 May 2022 13:21:51 -0700 In-Reply-To: <20220513202159.1550547-1-samitolvanen@google.com> Message-Id: <20220513202159.1550547-14-samitolvanen@google.com> Mime-Version: 1.0 References: <20220513202159.1550547-1-samitolvanen@google.com> X-Developer-Key: i=samitolvanen@google.com; a=openpgp; fpr=35CCFB63B283D6D3AEB783944CB5F6848BBC56EE X-Developer-Signature: v=1; a=openpgp-sha256; l=2492; h=from:subject; bh=O+VMkemg5E90usG6SsfLEV+HTvQnGaBlMMBcrxqTesI=; b=owEB7QES/pANAwAKAUy19oSLvFbuAcsmYgBifr3kE9sw78o8+eJw34YnMmYuK157n4APskm6j4x8 RWFsHcaJAbMEAAEKAB0WIQQ1zPtjsoPW0663g5RMtfaEi7xW7gUCYn695AAKCRBMtfaEi7xW7nURC/ wOdNWBO3UhCkvlEOcn4eL9iiDgGLHqd+ms7km80Bh8LZzW9sOnnlG3t3vRb52kdG5VEXtgkxioGv41 xDP0vHe/60Dqza8pTAK6oUDwZ9oravnzAdveNeysGT+iWwn6o+1PlLzaJmMM1WHiNJunt64I1Frt7l MG+kykOaX8IOtuUHQGbZHWos22oiPy9qAluaUwvZuPOkfOfDaZILICUJ+aOVo0YsM8pziu05P1lMyZ S6JU5H6j9BiCebv0Fc2EqSsSN5gNHjaRWhPBzA5au10tr+30q+wOqa1BHCK8mMAkmGTFUQZsKOfVyJ OcIxdboVGgRVBnDBRJCMZ8aytWoWx0G6HlaYhqS/WvOC1C4QDVu1DaIIC7FFX3v7KJB+D8zmwf7Tzo BbojzcBBfnmu6tJIxx1uUPt69XNi1OBt4xpbkBA8+eLJ4X7gmJouTVZo8KFUFQJeB6mF8MYQ1ttzhr h0OWEF+nFaDfGtzLvSL23nOGQJx8DP5aI9DLAbnTGhKs8= X-Mailer: git-send-email 2.36.0.550.gb090851708-goog Subject: [RFC PATCH v2 13/21] treewide: Drop WARN_ON_FUNCTION_MISMATCH From: Sami Tolvanen To: linux-kernel@vger.kernel.org Cc: Kees Cook , Josh Poimboeuf , Peter Zijlstra , x86@kernel.org, Catalin Marinas , Will Deacon , Mark Rutland , Nathan Chancellor , Nick Desaulniers , Joao Moreira , Sedat Dilek , Steven Rostedt , linux-hardening@vger.kernel.org, linux-arm-kernel@lists.infradead.org, llvm@lists.linux.dev, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org CONFIG_CFI_CLANG no longer breaks cross-module function address equality, which makes WARN_ON_FUNCTION_MISMATCH unnecessary. Remove the definition and switch back to WARN_ON_ONCE. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- include/asm-generic/bug.h | 16 ---------------- kernel/kthread.c | 3 +-- kernel/workqueue.c | 2 +- 3 files changed, 2 insertions(+), 19 deletions(-) diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h index ba1f860af38b..4050b191e1a9 100644 --- a/include/asm-generic/bug.h +++ b/include/asm-generic/bug.h @@ -220,22 +220,6 @@ extern __printf(1, 2) void __warn_printk(const char *fmt, ...); # define WARN_ON_SMP(x) ({0;}) #endif -/* - * WARN_ON_FUNCTION_MISMATCH() warns if a value doesn't match a - * function address, and can be useful for catching issues with - * callback functions, for example. - * - * With CONFIG_CFI_CLANG, the warning is disabled because the - * compiler replaces function addresses taken in C code with - * local jump table addresses, which breaks cross-module function - * address equality. - */ -#if defined(CONFIG_CFI_CLANG) && defined(CONFIG_MODULES) -# define WARN_ON_FUNCTION_MISMATCH(x, fn) ({ 0; }) -#else -# define WARN_ON_FUNCTION_MISMATCH(x, fn) WARN_ON_ONCE((x) != (fn)) -#endif - #endif /* __ASSEMBLY__ */ #endif diff --git a/kernel/kthread.c b/kernel/kthread.c index 50265f69a135..dfeb87876b4a 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -1050,8 +1050,7 @@ static void __kthread_queue_delayed_work(struct kthread_worker *worker, struct timer_list *timer = &dwork->timer; struct kthread_work *work = &dwork->work; - WARN_ON_FUNCTION_MISMATCH(timer->function, - kthread_delayed_work_timer_fn); + WARN_ON_ONCE(timer->function != kthread_delayed_work_timer_fn); /* * If @delay is 0, queue @dwork->work immediately. This is for diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 0d2514b4ff0d..18c1a1c09684 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1651,7 +1651,7 @@ static void __queue_delayed_work(int cpu, struct workqueue_struct *wq, struct work_struct *work = &dwork->work; WARN_ON_ONCE(!wq); - WARN_ON_FUNCTION_MISMATCH(timer->function, delayed_work_timer_fn); + WARN_ON_ONCE(timer->function != delayed_work_timer_fn); WARN_ON_ONCE(timer_pending(timer)); WARN_ON_ONCE(!list_empty(&work->entry));