From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.1 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E7522C43610 for ; Mon, 19 Nov 2018 17:27:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A3D8720C01 for ; Mon, 19 Nov 2018 17:27:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="al3YzVeC" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A3D8720C01 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404681AbeKTDvd (ORCPT ); Mon, 19 Nov 2018 22:51:33 -0500 Received: from mail-wm1-f68.google.com ([209.85.128.68]:36505 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404557AbeKTDvb (ORCPT ); Mon, 19 Nov 2018 22:51:31 -0500 Received: by mail-wm1-f68.google.com with SMTP id s11so6097766wmh.1 for ; Mon, 19 Nov 2018 09:27:07 -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=nn1bGI0lAecZVd/Nr8NjkoGpex3MA1HD9KRsJD9iBaE=; b=al3YzVeCj0YHhNT6cg0Cjcm8u0ncAy2aMGzZTXZmBtegGLPp2r2vS/AJZTwT7SL1V1 G7ymRvAYBgYbSCnWsgyJUCkbY4M087bjjhgwKwffeoOJZkm4H5MVbig26lZWKrrpyugY laWJcgG0cgDzgtN8+NEf/Iha4W6cl+INqnjWh0rK/vi5RvWuvaAN0qJwoj7nuwHz9FO8 PX7IhcrXscvAGA8VE5Nd0vgHVsO/z9IDKSL/xCCwkBoK1bB+u0M0vt2z9yHPeByUETUh +FkaBUwb8g+m4sfCg6fphwjcewjH/c/0YrgivC2giSPSBTQYyTpIfbyOo3rG2wmlx6FG qX6A== 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=nn1bGI0lAecZVd/Nr8NjkoGpex3MA1HD9KRsJD9iBaE=; b=sTrlb/RNIQdsBK8UVekyE93b7Jhi6ZvitJv+VqAnmskfIr9W5ZahDp7S0/u9K+kU0s NdeHHslnCAjXhYikC9QfGaarCU8RR1sIQQthceeiEFuzJefIIK1YTEER0BBVts86/xqf eu9UPdZnrFVppI4Q+SV+HZyXf1yLxkAIjwWEOBaBItYem0B+F9azyYXWxQ7yzbhwveTC MsJM1Nvv38OiPxiCs21XP3Jd3drNfPEhl745yeCK7xmRU7srKC3IcwYgNIIH8czRuTgr cfb7YDv02b0cyxtWwkxqhse7KsOWWQoz7agJsQKsN6F4BZ1BQsrVgnRJHqCCJBWTgXmc uxBw== X-Gm-Message-State: AGRZ1gIaYjJySOrm5RBUgKw2CH4CDUUscBmVCoT1Sq0TukyV8vXVPHC2 lI4LWXUDb3RJYx9IJO/ZABDauw== X-Google-Smtp-Source: AFSGD/WQMm489HnpI1eyiDD7CjXlAqXEJysYrdjjAsIWTnQ1RLMBImBnpeCFI1436TFPYvZWdfHBfw== X-Received: by 2002:a1c:7601:: with SMTP id r1mr7770386wmc.98.1542648426679; Mon, 19 Nov 2018 09:27:06 -0800 (PST) Received: from andreyknvl0.muc.corp.google.com ([2a00:79e0:15:10:3180:41f8:3010:ff61]) by smtp.gmail.com with ESMTPSA id l143-v6sm23685190wmb.23.2018.11.19.09.27.04 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 19 Nov 2018 09:27:05 -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 v11 08/24] kasan: initialize shadow to 0xff for tag-based mode Date: Mon, 19 Nov 2018 18:26:24 +0100 Message-Id: <1a06035a7777dedcc93680ca739c481fb068073d.1542648335.git.andreyknvl@google.com> X-Mailer: git-send-email 2.19.1.1215.g8438c0b245-goog In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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; -- 2.19.1.1215.g8438c0b245-goog