From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752735AbaIXMvj (ORCPT ); Wed, 24 Sep 2014 08:51:39 -0400 Received: from mailout4.w1.samsung.com ([210.118.77.14]:35284 "EHLO mailout4.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751533AbaIXMvY (ORCPT ); Wed, 24 Sep 2014 08:51:24 -0400 X-AuditID: cbfec7f5-b7f776d000003e54-f1-5422be4ad3bf From: Andrey Ryabinin To: linux-kernel@vger.kernel.org Cc: Andrey Ryabinin , Dmitry Vyukov , Konstantin Serebryany , Dmitry Chernenkov , Andrey Konovalov , Yuri Gribov , Konstantin Khlebnikov , Sasha Levin , Christoph Lameter , Joonsoo Kim , Andrew Morton , Dave Hansen , Andi Kleen , Vegard Nossum , "H. Peter Anvin" , Dave Jones , x86@kernel.org, linux-mm@kvack.org Subject: [PATCH v3 05/13] mm: page_alloc: add kasan hooks on alloc and free paths Date: Wed, 24 Sep 2014 16:44:01 +0400 Message-id: <1411562649-28231-6-git-send-email-a.ryabinin@samsung.com> X-Mailer: git-send-email 2.1.1 In-reply-to: <1411562649-28231-1-git-send-email-a.ryabinin@samsung.com> References: <1404905415-9046-1-git-send-email-a.ryabinin@samsung.com> <1411562649-28231-1-git-send-email-a.ryabinin@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrHLMWRmVeSWpSXmKPExsVy+t/xy7pe+5RCDBa+VrbY9usRm8XvvTNZ LeasX8NmceTad3aL69/eMFp8evmA0WLL9SYmi+cPH7JbTHjYxm4xbaO4xcruZjaL7c/eMlms 7HzAanF51xw2i3tr/rNaLD5ym9ni3bPJzBZXVx1kt/ix4TGrg7DH/J0fGT12zrrL7rFgU6nH 4j0vmTw2repk89j0aRK7R9fbK0weJ2b8ZvF4cmU6k8fHp7dYPN7vu8rm0bdlFaPH501yHida vrAG8EVx2aSk5mSWpRbp2yVwZUzedJix4JZqxcrPp9gbGHvkuxg5OSQETCTa/h5lhLDFJC7c W8/WxcjFISSwlFGid9tcFginj0li5r0n7CBVbAJ6Ev9mbWcDsUUEFCQ29z5jBSliFpjCKvFu +S6wUcICwRL3728FauDgYBFQlZiwKQkkzCvgJrFr/g1miG1yEnsnr2YBsTkF3CUO/HjBDrGs iVFi2d7fTBMYeRcwMqxiFE0tTS4oTkrPNdIrTswtLs1L10vOz93ECImTrzsYlx6zOsQowMGo xMM7UVwpRIg1say4MvcQowQHs5IIb9geoBBvSmJlVWpRfnxRaU5q8SFGJg5OqQbGPg3dksCj 7nfu6r1+dTpc79Vmd1HTNQmqm7Z9MPrz5X+48qHFy7pcb227q7Z8946VvecTdgYJTvW8ZvRj xkuZtXYFs8PKmtd4b7/BnGYqmMnxt3T3HuaSJ8vn7j1g3SYb/HKO44ytU27Up39+Y+hyr03x y6Gk2F++Ux8sSRM3LshoXtnOsMr1jhJLcUaioRZzUXEiANLTMztxAgAA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add kernel address sanitizer hooks to mark allocated page's addresses as accessible in corresponding shadow region. Mark freed pages as inaccessible. Signed-off-by: Andrey Ryabinin --- include/linux/kasan.h | 6 ++++++ mm/compaction.c | 2 ++ mm/kasan/kasan.c | 14 ++++++++++++++ mm/kasan/kasan.h | 1 + mm/kasan/report.c | 7 +++++++ mm/page_alloc.c | 3 +++ 6 files changed, 33 insertions(+) diff --git a/include/linux/kasan.h b/include/linux/kasan.h index 01c99fe..9714fba 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -30,6 +30,9 @@ static inline void kasan_disable_local(void) void kasan_unpoison_shadow(const void *address, size_t size); +void kasan_alloc_pages(struct page *page, unsigned int order); +void kasan_free_pages(struct page *page, unsigned int order); + #else /* CONFIG_KASAN */ static inline void kasan_unpoison_shadow(const void *address, size_t size) {} @@ -37,6 +40,9 @@ static inline void kasan_unpoison_shadow(const void *address, size_t size) {} static inline void kasan_enable_local(void) {} static inline void kasan_disable_local(void) {} +static inline void kasan_alloc_pages(struct page *page, unsigned int order) {} +static inline void kasan_free_pages(struct page *page, unsigned int order) {} + #endif /* CONFIG_KASAN */ #endif /* LINUX_KASAN_H */ diff --git a/mm/compaction.c b/mm/compaction.c index 92075d5..686b5c2 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "internal.h" #ifdef CONFIG_COMPACTION @@ -59,6 +60,7 @@ static void map_pages(struct list_head *list) list_for_each_entry(page, list, lru) { arch_alloc_page(page, 0); kernel_map_pages(page, 1, 1); + kasan_alloc_pages(page, 0); } } diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c index 454df8d..7cfc1fe 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -251,6 +251,20 @@ static __always_inline void check_memory_region(unsigned long addr, kasan_report_error(&info); } +void kasan_alloc_pages(struct page *page, unsigned int order) +{ + if (likely(!PageHighMem(page))) + kasan_unpoison_shadow(page_address(page), PAGE_SIZE << order); +} + +void kasan_free_pages(struct page *page, unsigned int order) +{ + if (likely(!PageHighMem(page))) + kasan_poison_shadow(page_address(page), + PAGE_SIZE << order, + KASAN_FREE_PAGE); +} + void __asan_load1(unsigned long addr) { check_memory_region(addr, 1, false); diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index 5895e31..5e61799 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -6,6 +6,7 @@ #define KASAN_SHADOW_SCALE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT) #define KASAN_SHADOW_MASK (KASAN_SHADOW_SCALE_SIZE - 1) +#define KASAN_FREE_PAGE 0xFF /* page was freed */ #define KASAN_SHADOW_GAP 0xF9 /* address belongs to shadow memory */ struct access_info { diff --git a/mm/kasan/report.c b/mm/kasan/report.c index bf559fa..f9d4e8d 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -57,6 +57,9 @@ static void print_error_description(struct access_info *info) case 0 ... KASAN_SHADOW_SCALE_SIZE - 1: bug_type = "out of bounds access"; break; + case KASAN_FREE_PAGE: + bug_type = "use after free"; + break; case KASAN_SHADOW_GAP: bug_type = "wild memory access"; break; @@ -75,6 +78,10 @@ static void print_address_description(struct access_info *info) page = virt_to_head_page((void *)info->access_addr); switch (shadow_val) { + case KASAN_FREE_PAGE: + dump_page(page, "kasan error"); + dump_stack(); + break; case KASAN_SHADOW_GAP: pr_err("No metainfo is available for this access.\n"); dump_stack(); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index ee95d0a..ef3604a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -59,6 +59,7 @@ #include #include #include +#include #include #include @@ -755,6 +756,7 @@ static bool free_pages_prepare(struct page *page, unsigned int order) trace_mm_page_free(page, order); kmemcheck_free_shadow(page, order); + kasan_free_pages(page, order); if (PageAnon(page)) page->mapping = NULL; @@ -941,6 +943,7 @@ static int prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags) arch_alloc_page(page, order); kernel_map_pages(page, 1 << order, 1); + kasan_alloc_pages(page, order); if (gfp_flags & __GFP_ZERO) prep_zero_page(page, order, gfp_flags); -- 2.1.1