From patchwork Wed Dec 6 10:24:04 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jinbum Park X-Patchwork-Id: 10095313 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id DA53360567 for ; Wed, 6 Dec 2017 10:24:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C819729C8C for ; Wed, 6 Dec 2017 10:24:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BD11329C8E; Wed, 6 Dec 2017 10:24:27 +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=-4.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id 8FF7B29CA3 for ; Wed, 6 Dec 2017 10:24:26 +0000 (UTC) Received: (qmail 7981 invoked by uid 550); 6 Dec 2017 10:24:24 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 7963 invoked from network); 6 Dec 2017 10:24:23 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:mime-version:content-disposition :user-agent; bh=ABzGhxfB5G0pNJOT8iUm+7OZtQNOycX11v2Ioh4LicM=; b=OGqwu6bCAyyfd8jHuHiI7QToYVmfzYxAHzDPIiNLrUm9E79fI1GfIb2bukGiPFnA6Z I70fT2OwDs7upbD/b8GOaWW1GTXG1wT5PqeU2xrccAcKRm8i3bWoljrImgQogQAwTQwD 22m+ZOTb2igQP+GLJBCs03yRGu/ksLTXgOz/tP2680azHX86Q5kRg+XYUKsntFTFoJbp vxWx0NAImxYXWOMhwq3plEyZjjmkhjQXL0gm1o6TPp5nxGejyoNiJZhBQfzNpb+bK0// WGTbYywJ+jJv8tuuqcDd5UXH6IpdCzpPHD2grsZ/FAPk1XF+lIg2Wp+vubx1RwgzrocQ Pssw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=ABzGhxfB5G0pNJOT8iUm+7OZtQNOycX11v2Ioh4LicM=; b=Z3DJNQbu2iymTa+zvPP3uV5dKXda2Mvz9KQ8tcr9k53oDSf0vV9Ho9TYmfj2TbByGj M7fDFpID/gmTsA29xV1iuQsabRthDqEnTyJ+fUmZEFCGIX9FSvCiHWH3oTrLlcFRHVae ypxceOA/70CYYNbQnUAKuZGJdhk81I6TETaY3O5jxYN+CisHXZjiOE66+KCiEuJovWW6 GDxRusvrRinT7jUiHRNrLaTckxtBUaEmH5x8+eex4sbAbcNOafKpI0x9UpINy/a5T1ou 6YmDoPt8nUcS9TBTlzHG5Rv8LMr1LBeoPxuzMJc0Tdi3A0ev21xHsIOK6MG07KuacBA/ shgA== X-Gm-Message-State: AKGB3mKQepSnvHJvbC4LRi/3tJUTXz4PJ7nUZ1f/T/3SooK8JPVLyqau ycgSSzofFDTfvqF3hiLI0Gc= X-Google-Smtp-Source: AGs4zMYDkbL0VQIWJa4YswSWsHfYTQAPvIIhdL8hpCyZOCd8oGJFRw2Oj/x2o63qdjUgc0IF+uALcg== X-Received: by 10.99.124.5 with SMTP id x5mr7421661pgc.310.1512555851867; Wed, 06 Dec 2017 02:24:11 -0800 (PST) Date: Wed, 6 Dec 2017 19:24:04 +0900 From: Jinbum Park To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com Cc: afzal.mohd.ma@gmail.com, mark.rutland@arm.com, labbott@redhat.com, linux@armlinux.org.uk, gregkh@linuxfoundation.org, keescook@chromium.org, vladimir.murzin@arm.com, arnd@arndb.de Message-ID: <20171206102404.GA7030@pjb1027-Latitude-E5410> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Subject: [kernel-hardening][PATCH v4 1/3] arm: mm: dump: make page table dumping reusable X-Virus-Scanned: ClamAV using ClamSMTP This patch refactors the arm page table dumping code, so multiple tables may be registered with the framework. This patch refers below commits of arm64. (4674fdb9f149 ("arm64: mm: dump: make page table dumping reusable")) (4ddb9bf83349 ("arm64: dump: Make ptdump debugfs a separate option")) Signed-off-by: Jinbum Park --- v4: No changes --- arch/arm/Kconfig.debug | 6 +++- arch/arm/include/asm/ptdump.h | 48 ++++++++++++++++++++++++++++++++ arch/arm/mm/Makefile | 3 +- arch/arm/mm/dump.c | 65 +++++++++++++++++++------------------------ arch/arm/mm/ptdump_debugfs.c | 34 ++++++++++++++++++++++ 5 files changed, 117 insertions(+), 39 deletions(-) create mode 100644 arch/arm/include/asm/ptdump.h create mode 100644 arch/arm/mm/ptdump_debugfs.c diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug index 17685e1..e7b94db 100644 --- a/arch/arm/Kconfig.debug +++ b/arch/arm/Kconfig.debug @@ -3,10 +3,14 @@ menu "Kernel hacking" source "lib/Kconfig.debug" -config ARM_PTDUMP +config ARM_PTDUMP_CORE + def_bool n + +config ARM_PTDUMP_DEBUGFS bool "Export kernel pagetable layout to userspace via debugfs" depends on DEBUG_KERNEL depends on MMU + select ARM_PTDUMP_CORE select DEBUG_FS ---help--- Say Y here if you want to show the kernel pagetable layout in a diff --git a/arch/arm/include/asm/ptdump.h b/arch/arm/include/asm/ptdump.h new file mode 100644 index 0000000..3a6c0b7 --- /dev/null +++ b/arch/arm/include/asm/ptdump.h @@ -0,0 +1,48 @@ +/* + * Copyright (C) 2014 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ +#ifndef __ASM_PTDUMP_H +#define __ASM_PTDUMP_H + +#ifdef CONFIG_ARM_PTDUMP_CORE + +#include +#include + +struct addr_marker { + unsigned long start_address; + char *name; +}; + +struct ptdump_info { + struct mm_struct *mm; + const struct addr_marker *markers; + unsigned long base_addr; +}; + +void ptdump_walk_pgd(struct seq_file *s, struct ptdump_info *info); +#ifdef CONFIG_ARM_PTDUMP_DEBUGFS +int ptdump_debugfs_register(struct ptdump_info *info, const char *name); +#else +static inline int ptdump_debugfs_register(struct ptdump_info *info, + const char *name) +{ + return 0; +} +#endif /* CONFIG_ARM_PTDUMP_DEBUGFS */ + +#endif /* CONFIG_ARM_PTDUMP_CORE */ + +#endif /* __ASM_PTDUMP_H */ diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile index 01bcc33..28be5f4 100644 --- a/arch/arm/mm/Makefile +++ b/arch/arm/mm/Makefile @@ -13,7 +13,8 @@ obj-y += nommu.o obj-$(CONFIG_ARM_MPU) += pmsa-v7.o endif -obj-$(CONFIG_ARM_PTDUMP) += dump.o +obj-$(CONFIG_ARM_PTDUMP_CORE) += dump.o +obj-$(CONFIG_ARM_PTDUMP_DEBUGFS) += ptdump_debugfs.o obj-$(CONFIG_MODULES) += proc-syms.o obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c index fc3b440..8dfe7c3 100644 --- a/arch/arm/mm/dump.c +++ b/arch/arm/mm/dump.c @@ -21,11 +21,7 @@ #include #include #include - -struct addr_marker { - unsigned long start_address; - const char *name; -}; +#include static struct addr_marker address_markers[] = { { MODULES_VADDR, "Modules" }, @@ -335,50 +331,36 @@ static void walk_pud(struct pg_state *st, pgd_t *pgd, unsigned long start) } } -static void walk_pgd(struct seq_file *m) +static void walk_pgd(struct pg_state *st, struct mm_struct *mm, + unsigned long start) { - pgd_t *pgd = swapper_pg_dir; - struct pg_state st; - unsigned long addr; + pgd_t *pgd = pgd_offset(mm, 0UL); unsigned i; - - memset(&st, 0, sizeof(st)); - st.seq = m; - st.marker = address_markers; + unsigned long addr; for (i = 0; i < PTRS_PER_PGD; i++, pgd++) { - addr = i * PGDIR_SIZE; + addr = start + i * PGDIR_SIZE; if (!pgd_none(*pgd)) { - walk_pud(&st, pgd, addr); + walk_pud(st, pgd, addr); } else { - note_page(&st, addr, 1, pgd_val(*pgd), NULL); + note_page(st, addr, 1, pgd_val(*pgd), NULL); } } - - note_page(&st, 0, 0, 0, NULL); } -static int ptdump_show(struct seq_file *m, void *v) +void ptdump_walk_pgd(struct seq_file *m, struct ptdump_info *info) { - walk_pgd(m); - return 0; -} + struct pg_state st = { + .seq = m, + .marker = info->markers, + }; -static int ptdump_open(struct inode *inode, struct file *file) -{ - return single_open(file, ptdump_show, NULL); + walk_pgd(&st, info->mm, info->base_addr); + note_page(&st, 0, 0, 0, NULL); } -static const struct file_operations ptdump_fops = { - .open = ptdump_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static int ptdump_init(void) +static void ptdump_initialize(void) { - struct dentry *pe; unsigned i, j; for (i = 0; i < ARRAY_SIZE(pg_level); i++) @@ -387,9 +369,18 @@ static int ptdump_init(void) pg_level[i].mask |= pg_level[i].bits[j].mask; address_markers[2].start_address = VMALLOC_START; +} - pe = debugfs_create_file("kernel_page_tables", 0400, NULL, NULL, - &ptdump_fops); - return pe ? 0 : -ENOMEM; +static struct ptdump_info kernel_ptdump_info = { + .mm = &init_mm, + .markers = address_markers, + .base_addr = 0, +}; + +static int ptdump_init(void) +{ + ptdump_initialize(); + return ptdump_debugfs_register(&kernel_ptdump_info, + "kernel_page_tables"); } __initcall(ptdump_init); diff --git a/arch/arm/mm/ptdump_debugfs.c b/arch/arm/mm/ptdump_debugfs.c new file mode 100644 index 0000000..be8d87b --- /dev/null +++ b/arch/arm/mm/ptdump_debugfs.c @@ -0,0 +1,34 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include + +#include + +static int ptdump_show(struct seq_file *m, void *v) +{ + struct ptdump_info *info = m->private; + + ptdump_walk_pgd(m, info); + return 0; +} + +static int ptdump_open(struct inode *inode, struct file *file) +{ + return single_open(file, ptdump_show, inode->i_private); +} + +static const struct file_operations ptdump_fops = { + .open = ptdump_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +int ptdump_debugfs_register(struct ptdump_info *info, const char *name) +{ + struct dentry *pe; + + pe = debugfs_create_file(name, 0400, NULL, info, &ptdump_fops); + return pe ? 0 : -ENOMEM; + +}