From patchwork Sun Jan 24 05:01:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 12042063 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_RED autolearn=ham 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 D24BFC433DB for ; Sun, 24 Jan 2021 05:01:43 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 736EE22CF6 for ; Sun, 24 Jan 2021 05:01:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 736EE22CF6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 19EF16B0022; Sun, 24 Jan 2021 00:01:43 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 0FFF66B0023; Sun, 24 Jan 2021 00:01:43 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 015996B0024; Sun, 24 Jan 2021 00:01:42 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0125.hostedemail.com [216.40.44.125]) by kanga.kvack.org (Postfix) with ESMTP id DF63C6B0022 for ; Sun, 24 Jan 2021 00:01:42 -0500 (EST) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 9ADCB8249980 for ; Sun, 24 Jan 2021 05:01:42 +0000 (UTC) X-FDA: 77739470844.13.wren57_410a2a52757a Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin13.hostedemail.com (Postfix) with ESMTP id 7B74718140B89 for ; Sun, 24 Jan 2021 05:01:42 +0000 (UTC) X-HE-Tag: wren57_410a2a52757a X-Filterd-Recvd-Size: 3849 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf32.hostedemail.com (Postfix) with ESMTP for ; Sun, 24 Jan 2021 05:01:42 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 8905F22D2C; Sun, 24 Jan 2021 05:01:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1611464501; bh=sh700x7Hu6vxNrBP4J9bML1JZ69fplcFrjgPi1lNSIc=; h=Date:From:To:Subject:In-Reply-To:From; b=pLOURBliCWTpM/V0kNtdFeaonQPu96t3IaXyxMJ1rkxPajuFq6BtERocScIv5gI00 Lxw+Kf2qdcsDF4gtpW4KxbdVUq3uzTkPNIUzoBKvxi7TvGRL1pBcIT5Yn+uATBChI5 FnYvKM0cz0r3JZ12DDz2Y2KLevY8l/L7yZqths2s= Date: Sat, 23 Jan 2021 21:01:38 -0800 From: Andrew Morton To: akpm@linux-foundation.org, andreyknvl@google.com, aryabinin@virtuozzo.com, Branislav.Rankov@arm.com, catalin.marinas@arm.com, dvyukov@google.com, elver@google.com, eugenis@google.com, glider@google.com, kevin.brodsky@arm.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, pcc@google.com, torvalds@linux-foundation.org, vbabka@suse.cz, vincenzo.frascino@arm.com, will.deacon@arm.com Subject: [patch 10/19] kasan, mm: fix conflicts with init_on_alloc/free Message-ID: <20210124050138.apmWliFQh%akpm@linux-foundation.org> In-Reply-To: <20210123210029.a7c704d0cab204683e41ad10@linux-foundation.org> User-Agent: s-nail v14.8.16 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: From: Andrey Konovalov Subject: kasan, mm: fix conflicts with init_on_alloc/free A few places where SLUB accesses object's data or metadata were missed in a previous patch. This leads to false positives with hardware tag-based KASAN when bulk allocations are used with init_on_alloc/free. Fix the false-positives by resetting pointer tags during these accesses. (The kasan_reset_tag call is removed from slab_alloc_node, as it's added into maybe_wipe_obj_freeptr.) Link: https://linux-review.googlesource.com/id/I50dd32838a666e173fe06c3c5c766f2c36aae901 Link: https://lkml.kernel.org/r/093428b5d2ca8b507f4a79f92f9929b35f7fada7.1610731872.git.andreyknvl@google.com Fixes: aa1ef4d7b3f67 ("kasan, mm: reset tags when accessing metadata") Signed-off-by: Andrey Konovalov Reported-by: Dmitry Vyukov Acked-by: Vlastimil Babka Cc: Catalin Marinas Cc: Vincenzo Frascino Cc: Alexander Potapenko Cc: Marco Elver Cc: Will Deacon Cc: Andrey Ryabinin Cc: Peter Collingbourne Cc: Evgenii Stepanov Cc: Branislav Rankov Cc: Kevin Brodsky Signed-off-by: Andrew Morton --- mm/slub.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/mm/slub.c~kasan-mm-fix-conflicts-with-init_on_alloc-free +++ a/mm/slub.c @@ -2791,7 +2791,8 @@ static __always_inline void maybe_wipe_o void *obj) { if (unlikely(slab_want_init_on_free(s)) && obj) - memset((void *)((char *)obj + s->offset), 0, sizeof(void *)); + memset((void *)((char *)kasan_reset_tag(obj) + s->offset), + 0, sizeof(void *)); } /* @@ -2883,7 +2884,7 @@ redo: stat(s, ALLOC_FASTPATH); } - maybe_wipe_obj_freeptr(s, kasan_reset_tag(object)); + maybe_wipe_obj_freeptr(s, object); if (unlikely(slab_want_init_on_alloc(gfpflags, s)) && object) memset(kasan_reset_tag(object), 0, s->object_size); @@ -3329,7 +3330,7 @@ int kmem_cache_alloc_bulk(struct kmem_ca int j; for (j = 0; j < i; j++) - memset(p[j], 0, s->object_size); + memset(kasan_reset_tag(p[j]), 0, s->object_size); } /* memcg and kmem_cache debug support */