From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754898AbbAUQ4b (ORCPT ); Wed, 21 Jan 2015 11:56:31 -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 S1753695AbbAUQwW (ORCPT ); Wed, 21 Jan 2015 11:52:22 -0500 X-AuditID: cbfec7f5-b7fc86d0000066b7-8d-54bfd8ada642 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, Pekka Enberg , David Rientjes Subject: [PATCH v9 06/17] mm: slub: introduce metadata_access_enable()/metadata_access_disable() Date: Wed, 21 Jan 2015 19:51:34 +0300 Message-id: <1421859105-25253-7-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+NgFrrILMWRmVeSWpSXmKPExsVy+t/xq7prb+wPMfi+RsZi269HbBa/985k tZizfg2bxZFr39ktrn97w2jx6eUDRovnDx+yW0x42MZusbK7mc1i+7O3TBYrOx+wWlzeNYfN 4t6a/6wWbZ//AYklG5ksFh+5zWzx7tlkZosfGx6zOgh5zN/5kdFj56y77B4LNpV6LN7zkslj 06pONo9Nnyaxe3S9vcLkcWLGbxaPJ1emM3l8fHqLxaNvyypGj8+b5AJ4orhsUlJzMstSi/Tt ErgylpzbyVJwmr/ixotWxgbGyzxdjJwcEgImEkuefWSHsMUkLtxbz9bFyMUhJLCUUeLP5StM EE4fk8Tc5l42kCo2AT2Jf7O2g9kiAgoSm3ufsYIUMQt8ZpF43HUNLCEskCSxesFVFhCbRUBV 4uWeNkYQm1fATWLa7XfMEOvkJDbeWcEKYnMKuEvMPD8RalsTo8TnI9vZJjDyLmBkWMUomlqa XFCclJ5rpFecmFtcmpeul5yfu4kREg1fdzAuPWZ1iFGAg1GJh1fCZ3+IEGtiWXFl7iFGCQ5m JRHe+deBQrwpiZVVqUX58UWlOanFhxiZODilGhgvVC9uP/95OefWhwHcTB5Hfi5/UlU1ZWbN btWbVpbL7vpkdb6NO9NkXylSf2zuxYDz7KfEnJzUdsi7yy990hKVEyMV+Loi63DgenuW6dnr LU2SL/bd23b99W/Du4ZWp/he1pRv0JrU5Blx3ON7iT3nDF61T6kPzzEXR8ve7ypbbfJyYfv7 aXOUWIozEg21mIuKEwFVS8SZZAIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Wrap access to object's metadata in external functions with metadata_access_enable()/metadata_access_disable() function calls. This hooks separates payload accesses from metadata accesses which might be useful for different checkers (e.g. KASan). Signed-off-by: Andrey Ryabinin --- mm/slub.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/mm/slub.c b/mm/slub.c index 18777c9..9747976 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -467,13 +467,23 @@ static int slub_debug; static char *slub_debug_slabs; static int disable_higher_order_debug; +static inline void metadata_access_enable(void) +{ +} + +static inline void metadata_access_disable(void) +{ +} + /* * Object debugging */ static void print_section(char *text, u8 *addr, unsigned int length) { + metadata_access_enable(); print_hex_dump(KERN_ERR, text, DUMP_PREFIX_ADDRESS, 16, 1, addr, length, 1); + metadata_access_disable(); } static struct track *get_track(struct kmem_cache *s, void *object, @@ -503,7 +513,9 @@ static void set_track(struct kmem_cache *s, void *object, trace.max_entries = TRACK_ADDRS_COUNT; trace.entries = p->addrs; trace.skip = 3; + metadata_access_enable(); save_stack_trace(&trace); + metadata_access_disable(); /* See rant in lockdep.c */ if (trace.nr_entries != 0 && @@ -677,7 +689,9 @@ static int check_bytes_and_report(struct kmem_cache *s, struct page *page, u8 *fault; u8 *end; + metadata_access_enable(); fault = memchr_inv(start, value, bytes); + metadata_access_disable(); if (!fault) return 1; @@ -770,7 +784,9 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page) if (!remainder) return 1; + metadata_access_enable(); fault = memchr_inv(end - remainder, POISON_INUSE, remainder); + metadata_access_disable(); if (!fault) return 1; while (end > fault && end[-1] == POISON_INUSE) -- 2.2.1