From patchwork Wed Aug 29 11:35:09 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10579933 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 B034E1709 for ; Wed, 29 Aug 2018 11:35:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9EFC42AA9C for ; Wed, 29 Aug 2018 11:35:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 920D02AB91; Wed, 29 Aug 2018 11:35:41 +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=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1BE302AA9C for ; Wed, 29 Aug 2018 11:35:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728514AbeH2PcG (ORCPT ); Wed, 29 Aug 2018 11:32:06 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:35315 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728473AbeH2PcF (ORCPT ); Wed, 29 Aug 2018 11:32:05 -0400 Received: by mail-wm0-f66.google.com with SMTP id o18-v6so5197154wmc.0 for ; Wed, 29 Aug 2018 04:35:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=y36bXvOzaMElAwP/XOX/nFNmvhGdVKzgjaE28JUMW5o=; b=J9lyKo7VWJ5jsaGwy1wNWax/WJQTvOe9FhDYud9wWj93OpsSu7DwWZsSZXOKoBVILO KPAyje7e5AQ7hfO8pvsIRzbA08oZTVo2DiKUtQXVxd+G8NDg5TtVpy2SWtuseVEcnGvG evNNyx49Q6IjYcQunMadL9ZRoGuPEWDHW8HnvBgxXuM3qx9w/KVTctwf/CAlAHO35Lyb MLUraaA2zKF6IR/MRT7GjoYhU+q8I0cNEAas1+bqk+CoYXEosJnObP4rz2Tj9gxsSIRh D4DFSGIABffoGHKHQPDQsFIniBny68STd7ZdYFa1kbbnspEUWtSqw/eLoqBMT6Ax9vJy JxAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=y36bXvOzaMElAwP/XOX/nFNmvhGdVKzgjaE28JUMW5o=; b=JiXzPQaoW4Fm+cwSGRmUT7pblQhB++BD6V4rpniNzYQTK0oSsdRJv4xfQpN4bjl3xs LyMRiiRaVy8vLlzqKoE9OQCvlRAWsus+lPtwm3ibpKZMdqhMDD8Y8PqnHdWSgAAY68AV oUOC46OIgezWXEPceuu3xCPJ+qSuJ4IXu/Ldk+4lCY2GtdJVvFPgaUBNgZhHHMN8I2FZ bLFv/B28KcwqC09tBrMCg3UjD+s7AIZWSJgWQBiIPlvS6UzpNPLLRuMy29UGbXX9ps05 RbOOXuzJgRBVS1mlpkySjTPSWpPSyLoy0R1kmXvd37F8K3b348Up2YpKKP+CL2i0UwZG zR3w== X-Gm-Message-State: APzg51C4FeVht5PEZ9yZdOn0DXXisq9NQGMx3U68DZSwUoGhQHQpEpfs 3Ip0+TLCIUHgHYeKOfc58/753g== X-Google-Smtp-Source: ANB0Vdat/kRDBTM8zngqNeGsn+KvYphqXvjyZ5bXDZLZHa+jSCgaLJ+GwsYRrGfyHH7Np21KuGVweA== X-Received: by 2002:a1c:1bca:: with SMTP id b193-v6mr3968967wmb.6.1535542535574; Wed, 29 Aug 2018 04:35:35 -0700 (PDT) Received: from andreyknvl0.muc.corp.google.com ([2a00:79e0:15:10:84be:a42a:826d:c530]) by smtp.gmail.com with ESMTPSA id s10-v6sm7800454wmd.22.2018.08.29.04.35.34 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 29 Aug 2018 04:35:34 -0700 (PDT) From: Andrey Konovalov To: Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , Catalin Marinas , Will Deacon , Christoph Lameter , Andrew Morton , Mark Rutland , Nick Desaulniers , Marc Zyngier , Dave Martin , Ard Biesheuvel , "Eric W . Biederman" , Ingo Molnar , Paul Lawrence , Geert Uytterhoeven , Arnd Bergmann , "Kirill A . Shutemov" , Greg Kroah-Hartman , Kate Stewart , Mike Rapoport , kasan-dev@googlegroups.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sparse@vger.kernel.org, linux-mm@kvack.org, linux-kbuild@vger.kernel.org Cc: Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Jann Horn , Mark Brand , Chintan Pandya , Vishwath Mohan , Andrey Konovalov Subject: [PATCH v6 05/18] khwasan: initialize shadow to 0xff Date: Wed, 29 Aug 2018 13:35:09 +0200 Message-Id: <4dcf8e38bf6ef331e351f0ba4a76c12666f9fc08.1535462971.git.andreyknvl@google.com> X-Mailer: git-send-email 2.19.0.rc0.228.g281dcd1b4d0-goog In-Reply-To: References: MIME-Version: 1.0 Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP A KHWASAN shadow memory cell contains a memory tag, that corresponds to the tag in the top byte of the pointer, that points to that memory. The native top byte value of kernel pointers is 0xff, so with KHWASAN we need to initialize shadow memory to 0xff. This commit does that. Signed-off-by: Andrey Konovalov --- arch/arm64/mm/kasan_init.c | 16 ++++++++++++++-- include/linux/kasan.h | 8 ++++++++ mm/kasan/common.c | 3 ++- 3 files changed, 24 insertions(+), 3 deletions(-) diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c index 12145874c02b..7a31e8ccbad2 100644 --- a/arch/arm64/mm/kasan_init.c +++ b/arch/arm64/mm/kasan_init.c @@ -44,6 +44,15 @@ static phys_addr_t __init kasan_alloc_zeroed_page(int node) return __pa(p); } +static phys_addr_t __init kasan_alloc_raw_page(int node) +{ + void *p = memblock_virt_alloc_try_nid_raw(PAGE_SIZE, PAGE_SIZE, + __pa(MAX_DMA_ADDRESS), + MEMBLOCK_ALLOC_ACCESSIBLE, + node); + return __pa(p); +} + static pte_t *__init kasan_pte_offset(pmd_t *pmdp, unsigned long addr, int node, bool early) { @@ -89,7 +98,9 @@ static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr, do { phys_addr_t page_phys = early ? __pa_symbol(kasan_zero_page) - : kasan_alloc_zeroed_page(node); + : kasan_alloc_raw_page(node); + if (!early) + memset(__va(page_phys), KASAN_SHADOW_INIT, PAGE_SIZE); next = addr + PAGE_SIZE; set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL)); } while (ptep++, addr = next, addr != end && pte_none(READ_ONCE(*ptep))); @@ -139,6 +150,7 @@ asmlinkage void __init kasan_early_init(void) KASAN_SHADOW_END - (1UL << (64 - KASAN_SHADOW_SCALE_SHIFT))); BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, PGDIR_SIZE)); BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE)); + kasan_pgd_populate(KASAN_SHADOW_START, KASAN_SHADOW_END, NUMA_NO_NODE, true); } @@ -235,7 +247,7 @@ void __init kasan_init(void) set_pte(&kasan_zero_pte[i], pfn_pte(sym_to_pfn(kasan_zero_page), PAGE_KERNEL_RO)); - memset(kasan_zero_page, 0, PAGE_SIZE); + memset(kasan_zero_page, KASAN_SHADOW_INIT, PAGE_SIZE); cpu_replace_ttbr1(lm_alias(swapper_pg_dir)); /* At this point kasan is fully initialized. Enable error messages */ diff --git a/include/linux/kasan.h b/include/linux/kasan.h index beb56a26fe9b..1c31bb089154 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -150,6 +150,8 @@ static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; } #ifdef CONFIG_KASAN_GENERIC +#define KASAN_SHADOW_INIT 0 + void kasan_cache_shrink(struct kmem_cache *cache); void kasan_cache_shutdown(struct kmem_cache *cache); @@ -160,4 +162,10 @@ static inline void kasan_cache_shutdown(struct kmem_cache *cache) {} #endif /* CONFIG_KASAN_GENERIC */ +#ifdef CONFIG_KASAN_HW + +#define KASAN_SHADOW_INIT 0xFF + +#endif /* CONFIG_KASAN_HW */ + #endif /* LINUX_KASAN_H */ diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 154010ba6c1f..bed8e13c6e1d 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -474,11 +474,12 @@ int kasan_module_alloc(void *addr, size_t size) ret = __vmalloc_node_range(shadow_size, 1, shadow_start, shadow_start + shadow_size, - GFP_KERNEL | __GFP_ZERO, + GFP_KERNEL, PAGE_KERNEL, VM_NO_GUARD, NUMA_NO_NODE, __builtin_return_address(0)); if (ret) { + __memset(ret, KASAN_SHADOW_INIT, shadow_size); find_vm_area(addr)->flags |= VM_KASAN; kmemleak_ignore(ret); return 0;