From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753809AbaIXMyn (ORCPT ); Wed, 24 Sep 2014 08:54:43 -0400 Received: from mailout3.w1.samsung.com ([210.118.77.13]:47921 "EHLO mailout3.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751753AbaIXMvb (ORCPT ); Wed, 24 Sep 2014 08:51:31 -0400 X-AuditID: cbfec7f4-b7f156d0000063c7-54-5422be5069a1 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, Pekka Enberg , David Rientjes Subject: [PATCH v3 08/13] mm: slub: introduce metadata_access_enable()/metadata_access_disable() Date: Wed, 24 Sep 2014 16:44:04 +0400 Message-id: <1411562649-28231-9-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+NgFnrBLMWRmVeSWpSXmKPExsVy+t/xy7oB+5RCDM58MbHY9usRm8XvvTNZ LeasX8NmceTad3aL69/eMFp8evmA0WLL9SYmi+cPH7JbTHjYxm4xbaO4xcruZjaL7c/eMlms 7HzAanF51xw2i3tr/rNatH3+BySWbGSyWHzkNrPFu2eTmS2urjrIbvFjw2NWB1GP+Ts/Mnrs nHWX3WPBplKPxXteMnlsWtXJ5rHp0yR2j663V5g8Tsz4zeLx5Mp0Jo+PT2+xeLzfd5XNo2/L KkaPz5vkPE60fGEN4IvisklJzcksSy3St0vgypi3bydzwWn+ig8935kaGC/zdDFycEgImEj0 dbN3MXICmWISF+6tZ+ti5OIQEljKKPF4VzMjhNPHJHH+chcLSBWbgJ7Ev1nb2UBsEQEFic29 z1hBipgF7rNK7F7wlgkkISyQJNG14DUjiM0ioCrRtOQPWAOvgJtE14P9LBDr5CT2Tl4NZnMK uEsc+PGCHWJbE6PEsr2/mSYw8i5gZFjFKJpamlxQnJSea6hXnJhbXJqXrpecn7uJERI7X3Yw Lj5mdYhRgINRiYd3grhSiBBrYllxZe4hRgkOZiUR3rA9QCHelMTKqtSi/Pii0pzU4kOMTByc Ug2MVUptcX4pYZuPvZqxMuW7pGtOzHW/PQU7j2yU2rGhIqFMqbPpSZrARDaN6bJmsi+qzrld 2MAZX3OU9U7tdIY0NeWIwK862+ezec1V8sld3biyY75jg8EBBlY9qfyMvwW/Gf6nT3dgWh7q c176rlfAZv6puy8tevS522Kq6vR9LUns21Usd81RYinOSDTUYi4qTgQA813+y3sCAAA= 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 82282f5..9b1f75c 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) -- 2.1.1