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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 1DBE7C433DB for ; Wed, 3 Mar 2021 00:45:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CFB5064FB4 for ; Wed, 3 Mar 2021 00:45:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238500AbhCCA1z (ORCPT ); Tue, 2 Mar 2021 19:27:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:49002 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350700AbhCBMX7 (ORCPT ); Tue, 2 Mar 2021 07:23:59 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id EEB7C64FA9; Tue, 2 Mar 2021 11:58:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1614686328; bh=Da2w0Gzz+DvdIC28O5XHDcst4j8QW91mF7nrsHEWCi4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qdt4XdxT43h015gdiuqWCKJkY6IiuYiQoGcrRxRgWtupiIr8xkxyps09aXgaRjio6 bt5yEZKeMSj/L/TXmxccn0OLsHMWk4Fv/1buMX2+Yb9zkJtd5viRlF68956Trekthy RuLBU7jysT3j6H7EHJdv8Ik0ooJYZC40ZkJVHc1WZWdbVdJSSYphvczhdWdBi2xmkj 4LLP1EnGfAWChd9uFHlsS62ysd71o4kE+esqUIZQt9Vxu92ilwkPTyEb7AsaqqbI/p h0cMCkwCDXMu8kV1Su7hS61+wnE8l6n1t1xrMIxO9bnW/2k4zjJyy+J+2CzyMi3Pe2 wizPp+l780IrQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Khalid Aziz , Jann Horn , Christoph Hellwig , Catalin Marinas , "David S . Miller" , Sasha Levin , sparclinux@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 10/21] sparc64: Use arch_validate_flags() to validate ADI flag Date: Tue, 2 Mar 2021 06:58:24 -0500 Message-Id: <20210302115835.63269-10-sashal@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210302115835.63269-1-sashal@kernel.org> References: <20210302115835.63269-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Khalid Aziz [ Upstream commit 147d8622f2a26ef34beacc60e1ed8b66c2fa457f ] When userspace calls mprotect() to enable ADI on an address range, do_mprotect_pkey() calls arch_validate_prot() to validate new protection flags. arch_validate_prot() for sparc looks at the first VMA associated with address range to verify if ADI can indeed be enabled on this address range. This has two issues - (1) Address range might cover multiple VMAs while arch_validate_prot() looks at only the first VMA, (2) arch_validate_prot() peeks at VMA without holding mmap lock which can result in race condition. arch_validate_flags() from commit c462ac288f2c ("mm: Introduce arch_validate_flags()") allows for VMA flags to be validated for all VMAs that cover the address range given by user while holding mmap lock. This patch updates sparc code to move the VMA check from arch_validate_prot() to arch_validate_flags() to fix above two issues. Suggested-by: Jann Horn Suggested-by: Christoph Hellwig Suggested-by: Catalin Marinas Signed-off-by: Khalid Aziz Reviewed-by: Catalin Marinas Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- arch/sparc/include/asm/mman.h | 54 +++++++++++++++++++---------------- 1 file changed, 29 insertions(+), 25 deletions(-) diff --git a/arch/sparc/include/asm/mman.h b/arch/sparc/include/asm/mman.h index f94532f25db1..274217e7ed70 100644 --- a/arch/sparc/include/asm/mman.h +++ b/arch/sparc/include/asm/mman.h @@ -57,35 +57,39 @@ static inline int sparc_validate_prot(unsigned long prot, unsigned long addr) { if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM | PROT_ADI)) return 0; - if (prot & PROT_ADI) { - if (!adi_capable()) - return 0; + return 1; +} - if (addr) { - struct vm_area_struct *vma; +#define arch_validate_flags(vm_flags) arch_validate_flags(vm_flags) +/* arch_validate_flags() - Ensure combination of flags is valid for a + * VMA. + */ +static inline bool arch_validate_flags(unsigned long vm_flags) +{ + /* If ADI is being enabled on this VMA, check for ADI + * capability on the platform and ensure VMA is suitable + * for ADI + */ + if (vm_flags & VM_SPARC_ADI) { + if (!adi_capable()) + return false; - vma = find_vma(current->mm, addr); - if (vma) { - /* ADI can not be enabled on PFN - * mapped pages - */ - if (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)) - return 0; + /* ADI can not be enabled on PFN mapped pages */ + if (vm_flags & (VM_PFNMAP | VM_MIXEDMAP)) + return false; - /* Mergeable pages can become unmergeable - * if ADI is enabled on them even if they - * have identical data on them. This can be - * because ADI enabled pages with identical - * data may still not have identical ADI - * tags on them. Disallow ADI on mergeable - * pages. - */ - if (vma->vm_flags & VM_MERGEABLE) - return 0; - } - } + /* Mergeable pages can become unmergeable + * if ADI is enabled on them even if they + * have identical data on them. This can be + * because ADI enabled pages with identical + * data may still not have identical ADI + * tags on them. Disallow ADI on mergeable + * pages. + */ + if (vm_flags & VM_MERGEABLE) + return false; } - return 1; + return true; } #endif /* CONFIG_SPARC64 */ -- 2.30.1