From patchwork Tue Nov 27 16:55:26 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10701025 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 5783314E2 for ; Tue, 27 Nov 2018 16:58:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 409A82C45B for ; Tue, 27 Nov 2018 16:58:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 349BC2C455; Tue, 27 Nov 2018 16:58:11 +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=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 30B712C455 for ; Tue, 27 Nov 2018 16:58:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731646AbeK1Dyh (ORCPT ); Tue, 27 Nov 2018 22:54:37 -0500 Received: from mail-wr1-f66.google.com ([209.85.221.66]:42572 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731583AbeK1Dyg (ORCPT ); Tue, 27 Nov 2018 22:54:36 -0500 Received: by mail-wr1-f66.google.com with SMTP id q18so23436286wrx.9 for ; Tue, 27 Nov 2018 08:56:04 -0800 (PST) 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=fztBcLEiYbKA/LtOsORIwty9Qmu1JSfLSmyXKXMabPw=; b=VN748MujAw+DWU1wO0qdoor5iHxQuGuy1rSmsVaXIjPu+qp7t1gkSORsGaUi+0f2Z3 aOXiZ5FMoUJXYwqkR1KMlJUvgIzVuATN/AkXP0OnHQ2oR7g4qW0RP0AYlMOcCN9wRapF FjHdh51W3QTBDzipTDU8Het6TyNhlLctUuCuQyxPK0Jh1vMbZhjKZkHuaBUByJ/stl4J YjnUrP1lc/GUlHkFl66SX1lfog0/MdcpT7+9kAdMzPPqRJpx87kcbyQZQqG7yoybRkhP u9It3Zkk6LuI74HWWSL5K7a+7Sj044hjHidCjblgFJ0TaqnsWHAWWzCGCBNfmL6bKRWa 2Tfw== 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=fztBcLEiYbKA/LtOsORIwty9Qmu1JSfLSmyXKXMabPw=; b=myf/43D54cPYboTT8B4IkCXJXDvGv7JxB2XakfiurmZbZMhJRkv5QW5+DBIrvhTBgC ntrYwDukjLPgpW1W7iAWgku8x/eWbX0sI4VPrnnpepRHWmuzL33qIfopW1qtysTYby9b U+YyPCxUbGeeI9DwVMTVeNgskj1aVmhN9ZwiJhpDxOOkMzgtwa7vip1yqxCOnFCZtmzQ rLgdimlavFKgMbr9xhDunXw3UO3QUmKX7gkXMc++MHtsjmHLljoYoEfVJWys9IiXBe5w 3rYn2Fj+WJ7f2e3ROACrI4ymx7Hb9zP/ZspVa2A9/XoAUbEqbzwpm9NxKlaD3oE9RXur Niww== X-Gm-Message-State: AA+aEWZWhoZtdRuiL9MjHONCgecMUmxHkXI/k22iG2c0fjfqU3KTs60q eqXlN+UBlo1Rpi+tCyWhg66tkw== X-Google-Smtp-Source: AFSGD/XGiJkmlg1UCiFrlHGtGTEw55szXT2tYUWA/NiNoHyYu4oBhIyXGW2YjdMJaFRQhK/jKyCjyg== X-Received: by 2002:adf:f703:: with SMTP id r3mr27665915wrp.93.1543337763264; Tue, 27 Nov 2018 08:56:03 -0800 (PST) Received: from andreyknvl0.muc.corp.google.com ([2a00:79e0:15:10:3180:41f8:3010:ff61]) by smtp.gmail.com with ESMTPSA id k73sm6383099wmd.36.2018.11.27.08.56.01 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 27 Nov 2018 08:56:02 -0800 (PST) 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 v12 08/25] kasan: initialize shadow to 0xff for tag-based mode Date: Tue, 27 Nov 2018 17:55:26 +0100 Message-Id: <9004fd16d56d8772775cf671a8fa66e54ed138dd.1543337629.git.andreyknvl@google.com> X-Mailer: git-send-email 2.20.0.rc0.387.gc7a69e6b6c-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 tag-based KASAN 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 tag-based KASAN we need to initialize shadow memory to 0xff. Reviewed-by: Andrey Ryabinin Reviewed-by: Dmitry Vyukov Signed-off-by: Andrey Konovalov --- arch/arm64/mm/kasan_init.c | 15 +++++++++++++-- include/linux/kasan.h | 8 ++++++++ mm/kasan/common.c | 3 ++- 3 files changed, 23 insertions(+), 3 deletions(-) diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c index 4ebc19422931..7a4a0904cac8 100644 --- a/arch/arm64/mm/kasan_init.c +++ b/arch/arm64/mm/kasan_init.c @@ -43,6 +43,15 @@ 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_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) { @@ -92,7 +101,9 @@ static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr, do { phys_addr_t page_phys = early ? __pa_symbol(kasan_early_shadow_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))); @@ -239,7 +250,7 @@ void __init kasan_init(void) pfn_pte(sym_to_pfn(kasan_early_shadow_page), PAGE_KERNEL_RO)); - memset(kasan_early_shadow_page, 0, PAGE_SIZE); + memset(kasan_early_shadow_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 ec22d548d0d7..c56af24bd3e7 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -153,6 +153,8 @@ 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); @@ -163,4 +165,10 @@ static inline void kasan_cache_shutdown(struct kmem_cache *cache) {} #endif /* CONFIG_KASAN_GENERIC */ +#ifdef CONFIG_KASAN_SW_TAGS + +#define KASAN_SHADOW_INIT 0xFF + +#endif /* CONFIG_KASAN_SW_TAGS */ + #endif /* LINUX_KASAN_H */ diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 5f68c93734ba..7134e75447ff 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;