From patchwork Mon Apr 22 18:57:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rick Edgecombe X-Patchwork-Id: 10911573 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 C2646161F for ; Mon, 22 Apr 2019 19:08:34 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B5F6B287AE for ; Mon, 22 Apr 2019 19:08:34 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A6A83287BF; Mon, 22 Apr 2019 19:08:34 +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,MAILING_LIST_MULTI, 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 B98C8287AE for ; Mon, 22 Apr 2019 19:08:33 +0000 (UTC) Received: (qmail 32238 invoked by uid 550); 22 Apr 2019 19:04:11 -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 31821 invoked from network); 22 Apr 2019 19:04:01 -0000 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,382,1549958400"; d="scan'208";a="136417158" From: Rick Edgecombe To: Borislav Petkov , Andy Lutomirski , Ingo Molnar Cc: linux-kernel@vger.kernel.org, x86@kernel.org, hpa@zytor.com, Thomas Gleixner , Nadav Amit , Dave Hansen , Peter Zijlstra , linux_dti@icloud.com, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, akpm@linux-foundation.org, kernel-hardening@lists.openwall.com, linux-mm@kvack.org, will.deacon@arm.com, ard.biesheuvel@linaro.org, kristen@linux.intel.com, deneen.t.dock@intel.com, Rick Edgecombe Subject: [PATCH v4 14/23] x86/mm/cpa: Add set_direct_map_ functions Date: Mon, 22 Apr 2019 11:57:56 -0700 Message-Id: <20190422185805.1169-15-rick.p.edgecombe@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190422185805.1169-1-rick.p.edgecombe@intel.com> References: <20190422185805.1169-1-rick.p.edgecombe@intel.com> X-Virus-Scanned: ClamAV using ClamSMTP Add two new functions set_direct_map_default_noflush() and set_direct_map_invalid_noflush() for setting the direct map alias for the page to its default valid permissions and to an invalid state that cannot be cached in a TLB, respectively. These functions do not flush the TLB. Note, __kernel_map_pages() does something similar but flushes the TLB and doesn't reset the permission bits to default on all architectures. Also add an ARCH config ARCH_HAS_SET_DIRECT_MAP for specifying whether these have an actual implementation or a default empty one. Cc: Dave Hansen Cc: Andy Lutomirski Cc: Peter Zijlstra Signed-off-by: Rick Edgecombe --- arch/Kconfig | 4 ++++ arch/x86/Kconfig | 1 + arch/x86/include/asm/set_memory.h | 3 +++ arch/x86/mm/pageattr.c | 14 +++++++++++--- include/linux/set_memory.h | 11 +++++++++++ 5 files changed, 30 insertions(+), 3 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 3ab446bd12ef..5e43fcbad4ca 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -249,6 +249,10 @@ config ARCH_HAS_FORTIFY_SOURCE config ARCH_HAS_SET_MEMORY bool +# Select if arch has all set_direct_map_invalid/default() functions +config ARCH_HAS_SET_DIRECT_MAP + bool + # Select if arch init_task must go in the __init_task_data section config ARCH_TASK_STRUCT_ON_STACK bool diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 2ec5e850b807..45d788354376 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -66,6 +66,7 @@ config X86 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE select ARCH_HAS_SET_MEMORY + select ARCH_HAS_SET_DIRECT_MAP select ARCH_HAS_STRICT_KERNEL_RWX select ARCH_HAS_STRICT_MODULE_RWX select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE diff --git a/arch/x86/include/asm/set_memory.h b/arch/x86/include/asm/set_memory.h index 07a25753e85c..ae7b909dc242 100644 --- a/arch/x86/include/asm/set_memory.h +++ b/arch/x86/include/asm/set_memory.h @@ -85,6 +85,9 @@ int set_pages_nx(struct page *page, int numpages); int set_pages_ro(struct page *page, int numpages); int set_pages_rw(struct page *page, int numpages); +int set_direct_map_invalid_noflush(struct page *page); +int set_direct_map_default_noflush(struct page *page); + extern int kernel_set_to_readonly; void set_kernel_text_rw(void); void set_kernel_text_ro(void); diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 4c570612e24e..3574550192c6 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -2209,8 +2209,6 @@ int set_pages_rw(struct page *page, int numpages) return set_memory_rw(addr, numpages); } -#ifdef CONFIG_DEBUG_PAGEALLOC - static int __set_pages_p(struct page *page, int numpages) { unsigned long tempaddr = (unsigned long) page_address(page); @@ -2249,6 +2247,17 @@ static int __set_pages_np(struct page *page, int numpages) return __change_page_attr_set_clr(&cpa, 0); } +int set_direct_map_invalid_noflush(struct page *page) +{ + return __set_pages_np(page, 1); +} + +int set_direct_map_default_noflush(struct page *page) +{ + return __set_pages_p(page, 1); +} + +#ifdef CONFIG_DEBUG_PAGEALLOC void __kernel_map_pages(struct page *page, int numpages, int enable) { if (PageHighMem(page)) @@ -2282,7 +2291,6 @@ void __kernel_map_pages(struct page *page, int numpages, int enable) } #ifdef CONFIG_HIBERNATION - bool kernel_page_present(struct page *page) { unsigned int level; diff --git a/include/linux/set_memory.h b/include/linux/set_memory.h index 2a986d282a97..b5071497b8cb 100644 --- a/include/linux/set_memory.h +++ b/include/linux/set_memory.h @@ -17,6 +17,17 @@ static inline int set_memory_x(unsigned long addr, int numpages) { return 0; } static inline int set_memory_nx(unsigned long addr, int numpages) { return 0; } #endif +#ifndef CONFIG_ARCH_HAS_SET_DIRECT_MAP +static inline int set_direct_map_invalid_noflush(struct page *page) +{ + return 0; +} +static inline int set_direct_map_default_noflush(struct page *page) +{ + return 0; +} +#endif + #ifndef set_mce_nospec static inline int set_mce_nospec(unsigned long pfn) {