From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90C71C4161F for ; Wed, 10 Mar 2021 17:47:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6C7026501D for ; Wed, 10 Mar 2021 17:47:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233851AbhCJRr0 (ORCPT ); Wed, 10 Mar 2021 12:47:26 -0500 Received: from pegase1.c-s.fr ([93.17.236.30]:44957 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233550AbhCJRqr (ORCPT ); Wed, 10 Mar 2021 12:46:47 -0500 Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 4Dwfdx2SRvz9v04R; Wed, 10 Mar 2021 18:46:45 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id WmbeklJhj_kR; Wed, 10 Mar 2021 18:46:45 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 4Dwfdx1Ychz9tytQ; Wed, 10 Mar 2021 18:46:45 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 07E3C8B78D; Wed, 10 Mar 2021 18:46:47 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id 3gf2xt6Nf4oI; Wed, 10 Mar 2021 18:46:46 +0100 (CET) Received: from po16121vm.idsi0.si.c-s.fr (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id C7E748B77E; Wed, 10 Mar 2021 18:46:46 +0100 (CET) Received: by po16121vm.idsi0.si.c-s.fr (Postfix, from userid 0) id A646967568; Wed, 10 Mar 2021 17:46:46 +0000 (UTC) Message-Id: In-Reply-To: References: From: Christophe Leroy Subject: [PATCH v2 07/15] powerpc/uaccess: Call might_fault() inconditionaly To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Date: Wed, 10 Mar 2021 17:46:46 +0000 (UTC) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit 6bfd93c32a50 ("powerpc: Fix incorrect might_sleep in __get_user/__put_user on kernel addresses") added a check to not call might_sleep() on kernel addresses. This was to enable the use of __get_user() in the alignment exception handler for any address. Then commit 95156f0051cb ("lockdep, mm: fix might_fault() annotation") added a check of the address space in might_fault(), based on set_fs() logic. But this didn't solve the powerpc alignment exception case as it didn't call set_fs(KERNEL_DS). Nowadays, set_fs() is gone, previous patch fixed the alignment exception handler and __get_user/__put_user are not supposed to be used anymore to read kernel memory. Therefore the is_kernel_addr() check has become useless and can be removed. Signed-off-by: Christophe Leroy --- arch/powerpc/include/asm/uaccess.h | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h index eaa828a6a419..c4bbc64758a0 100644 --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -77,8 +77,7 @@ __pu_failed: \ __typeof__(*(ptr)) __pu_val = (x); \ __typeof__(size) __pu_size = (size); \ \ - if (!is_kernel_addr((unsigned long)__pu_addr)) \ - might_fault(); \ + might_fault(); \ __chk_user_ptr(__pu_addr); \ __put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \ \ @@ -238,12 +237,12 @@ do { \ __typeof__(size) __gu_size = (size); \ \ __chk_user_ptr(__gu_addr); \ - if (do_allow && !is_kernel_addr((unsigned long)__gu_addr)) \ + if (do_allow) { \ might_fault(); \ - if (do_allow) \ __get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \ - else \ + } else { \ __get_user_size_allowed(__gu_val, __gu_addr, __gu_size, __gu_err); \ + } \ (x) = (__typeof__(*(ptr)))__gu_val; \ \ __gu_err; \ -- 2.25.0