From patchwork Wed Jun 20 17:39:51 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10478383 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 7064B60383 for ; Wed, 20 Jun 2018 17:46:52 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5C9F128DFB for ; Wed, 20 Jun 2018 17:46:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 503CD28E15; Wed, 20 Jun 2018 17:46:52 +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=-7.8 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=unavailable 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 E2E9328DFB for ; Wed, 20 Jun 2018 17:46:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754620AbeFTRkU (ORCPT ); Wed, 20 Jun 2018 13:40:20 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:39039 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754598AbeFTRkQ (ORCPT ); Wed, 20 Jun 2018 13:40:16 -0400 Received: by mail-wm0-f66.google.com with SMTP id p11-v6so971745wmc.4 for ; Wed, 20 Jun 2018 10:40:16 -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; bh=lLfYi37gaM0avQflOOXqZqRn7bz54yL74j4Bfvqwt8s=; b=bNv7vRVaaxLGr0gCwndaM6ZM8oO/i0DMKlm/AtlSi2rNOhic4Oi9E0oro1XOFGqpHD IXBBIBHM2PVLH11bIBJZdm/p16DSN2itB7+otjGP7RxxAyoFyZBgPn1bfiSoqI+kahgb T3YCPVPkOt12qmlvX3CGBJ5+nm4GMx6ob7dNj8c1q027Az9iAGTDlydKlL6u8Vb5Ebwu v65gl7GJ59HNdGKanCk5kr94lvhyC+Jp/kQWxb9nJrnMr+eGmfKEAmy5E92TKQkgGk7n ez0feT4O77UpxK49KK1uTpCAsgOVpJAF+l6ftn0ZJbhuFN8iQcqarv6t0x1r4CU8u654 oqVw== 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; bh=lLfYi37gaM0avQflOOXqZqRn7bz54yL74j4Bfvqwt8s=; b=rnY7DwZFsK4PDmKEC8Jq5tzy7pjmZLkgchomvGTcjYNpdfHh89VAn1Ghpq8b+DGa5j WcIoPux35nHkGRHS4nYBtuvB5MGzU7sxiXfhxAwck2N+MltiEkgcshuSsR+bmy6PoDLW ak4pkGdZcvCb52evhV4tfA9cDJJ46ahzEJCXdORnjyJQ92W5xtcGzAzFviZeO35aHNTc fADZmArh4zZXkJbAMuq6vvc/dGd6ivb8UOA+oC79BqUMjqC6ct70zoeFBeIsgcxe0Ki4 qAX2eMrznsuh6NhsB6HQGY9e6pjx/E+zpBwwvXichC7z42GgCYGqOfa7Yg9ua5W55ZYw pLwA== X-Gm-Message-State: APt69E12o/rjjocDdQnChq6kN16zF52EhfV2y6lqdpw3wyIOhhfxz097 zAnmYUCni0HhGgahwrGUHHvQ1w== X-Google-Smtp-Source: ADUXVKLJz9jElOdW8PoKdesAbOJxPunoe4UmBftvYga0gq4p83fjB/Oohe0VklbrYwMfHcS7pbZnzw== X-Received: by 2002:a1c:ad50:: with SMTP id w77-v6mr2599098wme.54.1529516415006; Wed, 20 Jun 2018 10:40:15 -0700 (PDT) Received: from andreyknvl0.muc.corp.google.com ([2a00:79e0:15:10:84be:a42a:826d:c530]) by smtp.gmail.com with ESMTPSA id f18-v6sm4388598wro.1.2018.06.20.10.40.13 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 20 Jun 2018 10:40:14 -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 , Andrey Konovalov Subject: [PATCH v3 05/17] khwasan: initialize shadow to 0xff Date: Wed, 20 Jun 2018 19:39:51 +0200 Message-Id: <29bf9a5e71137411b8238fb2b8535811a91adbe8.1529515183.git.andreyknvl@google.com> X-Mailer: git-send-email 2.18.0.rc1.244.gcf134e6275-goog In-Reply-To: References: 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 6608aa9b35ac..336385baf926 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -139,6 +139,8 @@ 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); @@ -149,4 +151,10 @@ 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 e78ebeff1f4c..656baa8984c7 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -473,11 +473,12 @@ 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;