From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754194AbbAUQwd (ORCPT ); Wed, 21 Jan 2015 11:52:33 -0500 Received: from mailout4.w1.samsung.com ([210.118.77.14]:37326 "EHLO mailout4.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753893AbbAUQwM (ORCPT ); Wed, 21 Jan 2015 11:52:12 -0500 X-AuditID: cbfec7f4-b7f126d000001e9a-83-54bfd8a92248 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 , x86@kernel.org, linux-mm@kvack.org Subject: [PATCH v9 03/17] mm: page_alloc: add kasan hooks on alloc and free paths Date: Wed, 21 Jan 2015 19:51:31 +0300 Message-id: <1421859105-25253-4-git-send-email-a.ryabinin@samsung.com> X-Mailer: git-send-email 2.2.1 In-reply-to: <1421859105-25253-1-git-send-email-a.ryabinin@samsung.com> References: <1404905415-9046-1-git-send-email-a.ryabinin@samsung.com> <1421859105-25253-1-git-send-email-a.ryabinin@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrKLMWRmVeSWpSXmKPExsVy+t/xq7orb+wPMej4Lmmx7dcjNovfe2ey WsxZv4bN4si17+wW17+9YbT49PIBo8Xzhw/ZLSY8bGO3WNndzGax/dlbJouVnQ9YLS7vmsNm cW/Nf1aLxUduM1u8ezaZ2eLHhsesDgIe83d+ZPTYOesuu8eCTaUei/e8ZPLYtKqTzWPTp0ns Hl1vrzB5nJjxm8XjyZXpTB4fn95i8ejbsorR4/MmuQCeKC6blNSczLLUIn27BK6MCx3dTAUr VSs+nTvB2MD4RK6LkZNDQsBEoqP9IzuELSZx4d56ti5GLg4hgaWMEldedrGCJIQE+pgkXvTL gthsAnoS/2ZtZwOxRQQUJDb3PmMFaWAWWMEi8eXaCkaQhLBAsMT1W8+Yuxg5OFgEVCXaFoEt 4BVwk2h/vJMJYpmcxMY7K8Dmcwq4S8w8P5EJYnETo8TnI9vZJjDyLmBkWMUomlqaXFCclJ5r qFecmFtcmpeul5yfu4kREvRfdjAuPmZ1iFGAg1GJh7cidH+IEGtiWXFl7iFGCQ5mJRHe+deB QrwpiZVVqUX58UWlOanFhxiZODilGhhb/z35OPXwiY7voRc6Np4S7E98Fyv0S85RMJJB+Meu DfPmOa5I/PHV4EyoO99xu33mezm/zboWVHVm9ZTHr2aVTr4gdP5G9tI/x2t3+vL9ubjYds2m 9W2/M0RW7hX4zxRipLLIybie43lpv6rafEnNlZI8M99Hx7gW1H24US11K1DzRVuWkniSEktx RqKhFnNRcSIAplJVT1gCAAA= 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 | 7 +++++++ mm/compaction.c | 2 ++ mm/kasan/kasan.c | 14 ++++++++++++++ mm/kasan/report.c | 11 +++++++++++ mm/page_alloc.c | 3 +++ 5 files changed, 37 insertions(+) diff --git a/include/linux/kasan.h b/include/linux/kasan.h index 063a3f3..a278ccc 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -11,6 +11,7 @@ struct page; #define KASAN_SHADOW_SCALE_SHIFT 3 #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL) +#define KASAN_FREE_PAGE 0xFF /* page was freed */ #define KASAN_SHADOW_GAP 0xF9 /* address belongs to shadow memory */ #include @@ -33,6 +34,9 @@ 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) {} @@ -40,6 +44,9 @@ 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 546e571..12f2c7d 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "internal.h" #ifdef CONFIG_COMPACTION @@ -61,6 +62,7 @@ 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 740d5b2..efe8105 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -247,6 +247,20 @@ static __always_inline void check_memory_region(unsigned long addr, kasan_report(addr, size, write); } +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); +} + #define DECLARE_ASAN_CHECK(size) \ void __asan_load##size(unsigned long addr) \ { \ diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 62b942a..7983ebb 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -54,6 +54,9 @@ static void print_error_description(struct access_info *info) shadow_val = *(u8 *)kasan_mem_to_shadow(info->first_bad_addr); switch (shadow_val) { + case KASAN_FREE_PAGE: + bug_type = "use after free"; + break; case 0 ... KASAN_SHADOW_SCALE_SIZE - 1: bug_type = "out of bounds access"; break; @@ -72,6 +75,14 @@ static void print_error_description(struct access_info *info) static void print_address_description(struct access_info *info) { + unsigned long addr = info->access_addr; + + if ((addr >= PAGE_OFFSET) && + (addr < (unsigned long)high_memory)) { + struct page *page = virt_to_head_page((void *)addr); + dump_page(page, "kasan: bad access detected"); + } + dump_stack(); } diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 7633c50..3a75171 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include #include @@ -807,6 +808,7 @@ 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; @@ -985,6 +987,7 @@ 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); -- 2.2.1