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=-14.4 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_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 95822C35280 for ; Wed, 2 Oct 2019 10:55:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3AF0821783 for ; Wed, 2 Oct 2019 10:55:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="TNtdJa+Q" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3AF0821783 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D125C6B0007; Wed, 2 Oct 2019 06:55:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CC1146B0008; Wed, 2 Oct 2019 06:55:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BAF7D6B000A; Wed, 2 Oct 2019 06:55:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0131.hostedemail.com [216.40.44.131]) by kanga.kvack.org (Postfix) with ESMTP id 931BA6B0007 for ; Wed, 2 Oct 2019 06:55:55 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id 2746982437C9 for ; Wed, 2 Oct 2019 10:55:55 +0000 (UTC) X-FDA: 75998539470.14.road18_6dcc10b62c81b X-HE-Tag: road18_6dcc10b62c81b X-Filterd-Recvd-Size: 16233 Received: from mail-pf1-f194.google.com (mail-pf1-f194.google.com [209.85.210.194]) by imf22.hostedemail.com (Postfix) with ESMTP for ; Wed, 2 Oct 2019 10:55:54 +0000 (UTC) Received: by mail-pf1-f194.google.com with SMTP id y22so10140115pfr.3 for ; Wed, 02 Oct 2019 03:55:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=wPzRaZnauK/aSS25BKAe52uX/PkUhE63Xm4WI7PnEsA=; b=TNtdJa+Q63hCSVXxOdIIEJnqKr19SpI6Jo84Y2RoN8/0QgK8KKKMqAN74Eu4r/cyau 6Z2zFYk3IPQem8dbBn8M8GXZZh352Q/owHbX2AM4kWlVQ33EUpWgtwYsFsB3JOOHNWwE 8Ghzd7eOwDtJ4xwW1kuE0g/sfx5RBWeKOs/2GPyIAVJPhj86BK5lMDMGUIMBgo4da+uv dBIxqYbF4hed3iD5O99xwcbI0B/iMJXjG8eEHriklXTkP46AFrAP//gIcSJfjfm3DS6C n12lxqfVlIh/aHCDu+pEeNbe2KxHmSoj6Jx8MWBdKrnpVFRFZ78UmXV5x5Lda0REU1XW N0iA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=wPzRaZnauK/aSS25BKAe52uX/PkUhE63Xm4WI7PnEsA=; b=H+2Hg7wvtbYf5ohJgWR5a63pNrcGXcciXOgxWCkAx1Lo8sr7gXmUka4StA2b9a+cL5 dVx+Tpr7OQ0SscbLIBQso2s5XDIpxiZQw6nQol477i+zeE7Qx6a2jYUDhGv19dI+hze+ k/FqrUKlQKxli9i9+vl15jMNPGtpD/O2yd+4L3vaUn6/U+ipGS0+t8FnwVoELNuMTFn8 DMyE02Au2gezhXYOBHbXFCm7r32l2c7sB++49uxUlSRhgDf2NuErMgpUwu8j0WIwZIJX mMzPlC3jo/+Ck/1IGnFoORy4G2Silw9r2xlOrODtZM3w1J02auMv7R6onI40muMJS2ar Krnw== X-Gm-Message-State: APjAAAVgL2KCjx6FCsc07cfQL3dAGTr7zNCyWP5llftnbCpNLLL9//AE 8V4vBCW45gLQteve6mTeP5US7UVkAWqygNiA+BSgAg== X-Google-Smtp-Source: APXvYqzdVOZR/Rrr3CmiD2/GFLvmWZAq+/eUBBXIJUqiUj6ypMzF4YEDjEESyJRRUqzSvDHupUWRG/3q2XfK0IO/SV8= X-Received: by 2002:a63:d20f:: with SMTP id a15mr3127214pgg.130.1570013752561; Wed, 02 Oct 2019 03:55:52 -0700 (PDT) MIME-Version: 1.0 References: <8d86d53e904bece0623cb8969cdc70f782fa2bae.1569995450.git.nickhu@andestech.com> In-Reply-To: <8d86d53e904bece0623cb8969cdc70f782fa2bae.1569995450.git.nickhu@andestech.com> From: Andrey Konovalov Date: Wed, 2 Oct 2019 12:55:41 +0200 Message-ID: Subject: Re: [PATCH v2 2/2] riscv: Add KASAN support To: Nick Hu Cc: alankao@andestech.com, paul.walmsley@sifive.com, Palmer Dabbelt , aou@eecs.berkeley.edu, Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , alexios.zavras@intel.com, Allison Randal , Anup.Patel@wdc.com, Thomas Gleixner , Greg Kroah-Hartman , atish.patra@wdc.com, Kate Stewart , linux-riscv@lists.infradead.org, LKML , kasan-dev , Linux Memory Management List Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Oct 2, 2019 at 8:16 AM Nick Hu wrote: > > This patch ports the feature Kernel Address SANitizer (KASAN). Hi Nick, Please also update KASAN documentation to mention that riscv is supported. Thanks! > > Note: The start address of shadow memory is at the beginning of kernel > space, which is 2^64 - (2^39 / 2) in SV39. The size of the kernel space is > 2^38 bytes so the size of shadow memory should be 2^38 / 8. Thus, the > shadow memory would not overlap with the fixmap area. > > There are currently two limitations in this port, > > 1. RV64 only: KASAN need large address space for extra shadow memory > region. > > 2. KASAN can't debug the modules since the modules are allocated in VMALLOC > area. We mapped the shadow memory, which corresponding to VMALLOC area, to > the kasan_early_shadow_page because we don't have enough physical space for > all the shadow memory corresponding to VMALLOC area. > > Signed-off-by: Nick Hu > --- > arch/riscv/Kconfig | 1 + > arch/riscv/include/asm/kasan.h | 27 ++++++++ > arch/riscv/include/asm/pgtable-64.h | 5 ++ > arch/riscv/include/asm/string.h | 9 +++ > arch/riscv/kernel/head.S | 3 + > arch/riscv/kernel/riscv_ksyms.c | 2 + > arch/riscv/kernel/setup.c | 5 ++ > arch/riscv/kernel/vmlinux.lds.S | 1 + > arch/riscv/lib/memcpy.S | 5 +- > arch/riscv/lib/memset.S | 5 +- > arch/riscv/mm/Makefile | 6 ++ > arch/riscv/mm/kasan_init.c | 104 ++++++++++++++++++++++++++++ > 12 files changed, 169 insertions(+), 4 deletions(-) > create mode 100644 arch/riscv/include/asm/kasan.h > create mode 100644 arch/riscv/mm/kasan_init.c > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 8eebbc8860bb..ca2fc8ba8550 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -61,6 +61,7 @@ config RISCV > select SPARSEMEM_STATIC if 32BIT > select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU > select HAVE_ARCH_MMAP_RND_BITS > + select HAVE_ARCH_KASAN if MMU && 64BIT > > config ARCH_MMAP_RND_BITS_MIN > default 18 if 64BIT > diff --git a/arch/riscv/include/asm/kasan.h b/arch/riscv/include/asm/kasan.h > new file mode 100644 > index 000000000000..eb9b1a2f641c > --- /dev/null > +++ b/arch/riscv/include/asm/kasan.h > @@ -0,0 +1,27 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* Copyright (C) 2019 Andes Technology Corporation */ > + > +#ifndef __ASM_KASAN_H > +#define __ASM_KASAN_H > + > +#ifndef __ASSEMBLY__ > + > +#ifdef CONFIG_KASAN > + > +#include > + > +#define KASAN_SHADOW_SCALE_SHIFT 3 > + > +#define KASAN_SHADOW_SIZE (UL(1) << (38 - KASAN_SHADOW_SCALE_SHIFT)) > +#define KASAN_SHADOW_START 0xffffffc000000000 // 2^64 - 2^38 > +#define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE) > + > +#define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << \ > + (64 - KASAN_SHADOW_SCALE_SHIFT))) > + > +void kasan_init(void); > +asmlinkage void kasan_early_init(void); > + > +#endif > +#endif > +#endif /* __ASM_KASAN_H */ > diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h > index 7df8daa66cc8..777a1dddb3df 100644 > --- a/arch/riscv/include/asm/pgtable-64.h > +++ b/arch/riscv/include/asm/pgtable-64.h > @@ -59,6 +59,11 @@ static inline unsigned long pud_page_vaddr(pud_t pud) > return (unsigned long)pfn_to_virt(pud_val(pud) >> _PAGE_PFN_SHIFT); > } > > +static inline struct page *pud_page(pud_t pud) > +{ > + return pfn_to_page(pud_val(pud) >> _PAGE_PFN_SHIFT); > +} > + > #define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)) > > static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr) > diff --git a/arch/riscv/include/asm/string.h b/arch/riscv/include/asm/string.h > index 1b5d44585962..a4451f768826 100644 > --- a/arch/riscv/include/asm/string.h > +++ b/arch/riscv/include/asm/string.h > @@ -11,8 +11,17 @@ > > #define __HAVE_ARCH_MEMSET > extern asmlinkage void *memset(void *, int, size_t); > +extern asmlinkage void *__memset(void *, int, size_t); > > #define __HAVE_ARCH_MEMCPY > extern asmlinkage void *memcpy(void *, const void *, size_t); > +extern asmlinkage void *__memcpy(void *, const void *, size_t); > > +// For those files which don't want to check by kasan. > +#if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__) > + > +#define memcpy(dst, src, len) __memcpy(dst, src, len) > +#define memset(s, c, n) __memset(s, c, n) > + > +#endif > #endif /* _ASM_RISCV_STRING_H */ > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S > index 72f89b7590dd..95eca23cd811 100644 > --- a/arch/riscv/kernel/head.S > +++ b/arch/riscv/kernel/head.S > @@ -102,6 +102,9 @@ clear_bss_done: > sw zero, TASK_TI_CPU(tp) > la sp, init_thread_union + THREAD_SIZE > > +#ifdef CONFIG_KASAN > + call kasan_early_init > +#endif > /* Start the kernel */ > call parse_dtb > tail start_kernel > diff --git a/arch/riscv/kernel/riscv_ksyms.c b/arch/riscv/kernel/riscv_ksyms.c > index 4800cf703186..376bba7f65ce 100644 > --- a/arch/riscv/kernel/riscv_ksyms.c > +++ b/arch/riscv/kernel/riscv_ksyms.c > @@ -14,3 +14,5 @@ EXPORT_SYMBOL(__asm_copy_to_user); > EXPORT_SYMBOL(__asm_copy_from_user); > EXPORT_SYMBOL(memset); > EXPORT_SYMBOL(memcpy); > +EXPORT_SYMBOL(__memset); > +EXPORT_SYMBOL(__memcpy); > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c > index a990a6cb184f..41f7eae9bc4d 100644 > --- a/arch/riscv/kernel/setup.c > +++ b/arch/riscv/kernel/setup.c > @@ -23,6 +23,7 @@ > #include > #include > #include > +#include > > #ifdef CONFIG_DUMMY_CONSOLE > struct screen_info screen_info = { > @@ -70,6 +71,10 @@ void __init setup_arch(char **cmdline_p) > swiotlb_init(1); > #endif > > +#ifdef CONFIG_KASAN > + kasan_init(); > +#endif > + > #ifdef CONFIG_SMP > setup_smp(); > #endif > diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S > index 23cd1a9e52a1..97009803ba9f 100644 > --- a/arch/riscv/kernel/vmlinux.lds.S > +++ b/arch/riscv/kernel/vmlinux.lds.S > @@ -46,6 +46,7 @@ SECTIONS > KPROBES_TEXT > ENTRY_TEXT > IRQENTRY_TEXT > + SOFTIRQENTRY_TEXT > *(.fixup) > _etext = .; > } > diff --git a/arch/riscv/lib/memcpy.S b/arch/riscv/lib/memcpy.S > index b4c477846e91..51ab716253fa 100644 > --- a/arch/riscv/lib/memcpy.S > +++ b/arch/riscv/lib/memcpy.S > @@ -7,7 +7,8 @@ > #include > > /* void *memcpy(void *, const void *, size_t) */ > -ENTRY(memcpy) > +ENTRY(__memcpy) > +WEAK(memcpy) > move t6, a0 /* Preserve return value */ > > /* Defer to byte-oriented copy for small sizes */ > @@ -104,4 +105,4 @@ ENTRY(memcpy) > bltu a1, a3, 5b > 6: > ret > -END(memcpy) > +END(__memcpy) > diff --git a/arch/riscv/lib/memset.S b/arch/riscv/lib/memset.S > index 5a7386b47175..34c5360c6705 100644 > --- a/arch/riscv/lib/memset.S > +++ b/arch/riscv/lib/memset.S > @@ -8,7 +8,8 @@ > #include > > /* void *memset(void *, int, size_t) */ > -ENTRY(memset) > +ENTRY(__memset) > +WEAK(memset) > move t0, a0 /* Preserve return value */ > > /* Defer to byte-oriented fill for small sizes */ > @@ -109,4 +110,4 @@ ENTRY(memset) > bltu t0, a3, 5b > 6: > ret > -END(memset) > +END(__memset) > diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile > index 9d9a17335686..b8a8ca71f86e 100644 > --- a/arch/riscv/mm/Makefile > +++ b/arch/riscv/mm/Makefile > @@ -17,3 +17,9 @@ ifeq ($(CONFIG_MMU),y) > obj-$(CONFIG_SMP) += tlbflush.o > endif > obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o > +obj-$(CONFIG_KASAN) += kasan_init.o > + > +ifdef CONFIG_KASAN > +KASAN_SANITIZE_kasan_init.o := n > +KASAN_SANITIZE_init.o := n > +endif > diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c > new file mode 100644 > index 000000000000..c3152768cdbe > --- /dev/null > +++ b/arch/riscv/mm/kasan_init.c > @@ -0,0 +1,104 @@ > +// SPDX-License-Identifier: GPL-2.0 > +// Copyright (C) 2019 Andes Technology Corporation > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +extern pgd_t early_pg_dir[PTRS_PER_PGD]; > +asmlinkage void __init kasan_early_init(void) > +{ > + uintptr_t i; > + pgd_t *pgd = early_pg_dir + pgd_index(KASAN_SHADOW_START); > + > + for (i = 0; i < PTRS_PER_PTE; ++i) > + set_pte(kasan_early_shadow_pte + i, > + mk_pte(virt_to_page(kasan_early_shadow_page), > + PAGE_KERNEL)); > + > + for (i = 0; i < PTRS_PER_PMD; ++i) > + set_pmd(kasan_early_shadow_pmd + i, > + pfn_pmd(PFN_DOWN(__pa((uintptr_t)kasan_early_shadow_pte)), > + __pgprot(_PAGE_TABLE))); > + > + for (i = KASAN_SHADOW_START; i < KASAN_SHADOW_END; > + i += PGDIR_SIZE, ++pgd) > + set_pgd(pgd, > + pfn_pgd(PFN_DOWN(__pa(((uintptr_t)kasan_early_shadow_pmd))), > + __pgprot(_PAGE_TABLE))); > + > + // init for swapper_pg_dir > + pgd = pgd_offset_k(KASAN_SHADOW_START); > + > + for (i = KASAN_SHADOW_START; i < KASAN_SHADOW_END; > + i += PGDIR_SIZE, ++pgd) > + set_pgd(pgd, > + pfn_pgd(PFN_DOWN(__pa(((uintptr_t)kasan_early_shadow_pmd))), > + __pgprot(_PAGE_TABLE))); > + > + flush_tlb_all(); > +} > + > +static void __init populate(void *start, void *end) > +{ > + unsigned long i; > + unsigned long vaddr = (unsigned long)start & PAGE_MASK; > + unsigned long vend = PAGE_ALIGN((unsigned long)end); > + unsigned long n_pages = (vend - vaddr) / PAGE_SIZE; > + unsigned long n_pmds = > + (n_pages % PTRS_PER_PTE) ? n_pages / PTRS_PER_PTE + 1 : > + n_pages / PTRS_PER_PTE; > + pgd_t *pgd = pgd_offset_k(vaddr); > + pmd_t *pmd = memblock_alloc(n_pmds * sizeof(pmd_t), PAGE_SIZE); > + pte_t *pte = memblock_alloc(n_pages * sizeof(pte_t), PAGE_SIZE); > + > + for (i = 0; i < n_pages; i++) { > + phys_addr_t phys = memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); > + > + set_pte(pte + i, pfn_pte(PHYS_PFN(phys), PAGE_KERNEL)); > + } > + > + for (i = 0; i < n_pages; ++pmd, i += PTRS_PER_PTE) > + set_pmd(pmd, pfn_pmd(PFN_DOWN(__pa((uintptr_t)(pte + i))), > + __pgprot(_PAGE_TABLE))); > + > + for (i = vaddr; i < vend; i += PGDIR_SIZE, ++pgd) > + set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(((uintptr_t)pmd))), > + __pgprot(_PAGE_TABLE))); > + > + flush_tlb_all(); > + memset(start, 0, end - start); > +} > + > +void __init kasan_init(void) > +{ > + struct memblock_region *reg; > + unsigned long i; > + > + kasan_populate_early_shadow((void *)KASAN_SHADOW_START, > + (void *)kasan_mem_to_shadow((void *)VMALLOC_END)); > + > + for_each_memblock(memory, reg) { > + void *start = (void *)__va(reg->base); > + void *end = (void *)__va(reg->base + reg->size); > + > + if (start >= end) > + break; > + > + populate(kasan_mem_to_shadow(start), > + kasan_mem_to_shadow(end)); > + }; > + > + for (i = 0; i < PTRS_PER_PTE; i++) > + set_pte(&kasan_early_shadow_pte[i], > + mk_pte(virt_to_page(kasan_early_shadow_page), > + __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_ACCESSED))); > + > + memset(kasan_early_shadow_page, 0, PAGE_SIZE); > + init_task.kasan_depth = 0; > +} > -- > 2.17.0 > > -- > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@googlegroups.com. > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/8d86d53e904bece0623cb8969cdc70f782fa2bae.1569995450.git.nickhu%40andestech.com.