From patchwork Sun May 26 13:47:33 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Ghiti X-Patchwork-Id: 10961555 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 035DC6C5 for ; Sun, 26 May 2019 13:49:36 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E308728A5D for ; Sun, 26 May 2019 13:49:35 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D6E3C28A89; Sun, 26 May 2019 13:49:35 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 804DA28A5D for ; Sun, 26 May 2019 13:49:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=zl95GtdWoQVw0oKv1SrmDF+cYhV5ilIKDJ8auWpbuGk=; b=pKlCv7ce8rVUmS ZCdY8V/uIw9M4kahxlFLYkwFvJ+WuF0hT4qo8jmXddV8iwdeiiaFFD/pHgEbRkDizG6LHH0s2Mr0B e5Te2dd0rGWk4eigGUlZ2e8nHLpBDQ65iqwAWlBBT5eHmjjfWYm6PIv7l7z49o9rWP7U9kbyFL8v1 9ksY5Cv2mysyzwCLx4rbwEs4Kp5UxXs3sRxJojowbSmtW1LfVBaQX1y60irq1+gyMb6fX2oAuDyTh pUSysp0mL3OIsrdQbYukX/QAsxCf+pmvB7Ea8ksyj6q2/FguEFR0zwUxDH6Z/yUgsaXpHaH6aiUzf zvHxTr57QunRBSSveYtQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hUtWl-0003sa-Fw; Sun, 26 May 2019 13:49:31 +0000 Received: from relay7-d.mail.gandi.net ([217.70.183.200]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hUtWd-0003kb-3F; Sun, 26 May 2019 13:49:24 +0000 X-Originating-IP: 79.86.19.127 Received: from alex.numericable.fr (127.19.86.79.rev.sfr.net [79.86.19.127]) (Authenticated sender: alex@ghiti.fr) by relay7-d.mail.gandi.net (Postfix) with ESMTPSA id 16C8C20002; Sun, 26 May 2019 13:48:58 +0000 (UTC) From: Alexandre Ghiti To: Andrew Morton Subject: [PATCH v4 01/14] mm, fs: Move randomize_stack_top from fs to mm Date: Sun, 26 May 2019 09:47:33 -0400 Message-Id: <20190526134746.9315-2-alex@ghiti.fr> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190526134746.9315-1-alex@ghiti.fr> References: <20190526134746.9315-1-alex@ghiti.fr> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190526_064923_436045_CF9DA95A X-CRM114-Status: GOOD ( 12.60 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Albert Ou , Kees Cook , Alexandre Ghiti , Catalin Marinas , Palmer Dabbelt , Will Deacon , Russell King , Ralf Baechle , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Paul Burton , Alexander Viro , James Hogan , linux-fsdevel@vger.kernel.org, linux-riscv@lists.infradead.org, linux-mips@vger.kernel.org, Christoph Hellwig , linux-arm-kernel@lists.infradead.org, Luis Chamberlain Sender: "linux-riscv" Errors-To: linux-riscv-bounces+patchwork-linux-riscv=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP This preparatory commit moves this function so that further introduction of generic topdown mmap layout is contained only in mm/util.c. Signed-off-by: Alexandre Ghiti Acked-by: Kees Cook Reviewed-by: Christoph Hellwig --- fs/binfmt_elf.c | 20 -------------------- include/linux/mm.h | 2 ++ mm/util.c | 22 ++++++++++++++++++++++ 3 files changed, 24 insertions(+), 20 deletions(-) diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index fa9e99a962e0..d4d2fe109ee9 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -669,26 +669,6 @@ static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex, * libraries. There is no binary dependent code anywhere else. */ -#ifndef STACK_RND_MASK -#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */ -#endif - -static unsigned long randomize_stack_top(unsigned long stack_top) -{ - unsigned long random_variable = 0; - - if (current->flags & PF_RANDOMIZE) { - random_variable = get_random_long(); - random_variable &= STACK_RND_MASK; - random_variable <<= PAGE_SHIFT; - } -#ifdef CONFIG_STACK_GROWSUP - return PAGE_ALIGN(stack_top) + random_variable; -#else - return PAGE_ALIGN(stack_top) - random_variable; -#endif -} - static int load_elf_binary(struct linux_binprm *bprm) { struct file *interpreter = NULL; /* to shut gcc up */ diff --git a/include/linux/mm.h b/include/linux/mm.h index 0e8834ac32b7..446ec32c62b8 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2368,6 +2368,8 @@ extern int install_special_mapping(struct mm_struct *mm, unsigned long addr, unsigned long len, unsigned long flags, struct page **pages); +unsigned long randomize_stack_top(unsigned long stack_top); + extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); extern unsigned long mmap_region(struct file *file, unsigned long addr, diff --git a/mm/util.c b/mm/util.c index e2e4f8c3fa12..dab33b896146 100644 --- a/mm/util.c +++ b/mm/util.c @@ -14,6 +14,8 @@ #include #include #include +#include +#include #include @@ -291,6 +293,26 @@ int vma_is_stack_for_current(struct vm_area_struct *vma) return (vma->vm_start <= KSTK_ESP(t) && vma->vm_end >= KSTK_ESP(t)); } +#ifndef STACK_RND_MASK +#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */ +#endif + +unsigned long randomize_stack_top(unsigned long stack_top) +{ + unsigned long random_variable = 0; + + if (current->flags & PF_RANDOMIZE) { + random_variable = get_random_long(); + random_variable &= STACK_RND_MASK; + random_variable <<= PAGE_SHIFT; + } +#ifdef CONFIG_STACK_GROWSUP + return PAGE_ALIGN(stack_top) + random_variable; +#else + return PAGE_ALIGN(stack_top) - random_variable; +#endif +} + #if defined(CONFIG_MMU) && !defined(HAVE_ARCH_PICK_MMAP_LAYOUT) void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) {