From mboxrd@z Thu Jan 1 00:00:00 1970 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=-16.6 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 B45A6C433DB for ; Wed, 13 Jan 2021 16:04:27 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 36665233FC for ; Wed, 13 Jan 2021 16:04:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 36665233FC Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 4511D8D0064; Wed, 13 Jan 2021 11:04:26 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 401718D0063; Wed, 13 Jan 2021 11:04:26 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 316178D0064; Wed, 13 Jan 2021 11:04:26 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0020.hostedemail.com [216.40.44.20]) by kanga.kvack.org (Postfix) with ESMTP id 0F4208D0063 for ; Wed, 13 Jan 2021 11:04:26 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id DBB343635 for ; Wed, 13 Jan 2021 16:04:22 +0000 (UTC) X-FDA: 77701224006.28.debt96_4001abb2751f Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin28.hostedemail.com (Postfix) with ESMTP id 9306B2471 for ; Wed, 13 Jan 2021 16:03:44 +0000 (UTC) X-HE-Tag: debt96_4001abb2751f X-Filterd-Recvd-Size: 5133 Received: from mail-qk1-f202.google.com (mail-qk1-f202.google.com [209.85.222.202]) by imf03.hostedemail.com (Postfix) with ESMTP for ; Wed, 13 Jan 2021 16:03:38 +0000 (UTC) Received: by mail-qk1-f202.google.com with SMTP id i82so1649446qke.19 for ; Wed, 13 Jan 2021 08:03:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=S1gB0mX83HDDRDaVYmLzCgZEsoFxFZ697ly4fdy8+Ks=; b=onsW+t/YsYPW7Svrw7yWD2kvrRWEmrDqD+BcstXXpVYE27xuAbQnuH366baXFUJt7P q2byhvdnZS2pHRQEfzr8dVbYqGDMqWhQdCNgsLaH5LgIYs+rBzpKTp8X1s5UfXlW31fo e/LF6hRisIMf3tNYOwJcmN8ctzKnUVwtEIRdZdB2mCsOgt7eokJxnt8i1AF4kDp+r/Jn eMgyMsESgMNLluf6Q0Z8B4w9PFFgPGXC/zypWRSttrijEeUX1QAA6paSYDx1Ux9nv/MR oGsZEZ5ILg/XHhL4Wc9leIItNY5bZTBM2ML71iw/WcHGEoCcZ6vk7T14I7OM8Z3hQDyB fI0A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=S1gB0mX83HDDRDaVYmLzCgZEsoFxFZ697ly4fdy8+Ks=; b=q+FSlj4ULZWD/D/iNhCQywQD7ZpOPkpt1V/0ubCqjRw85mPowpbCJKCd/TxY+W0igX SMQZCLcBtKlBaFZrQUTMbS883jMeEWPym14/KgNZpSc0ilPLQ0IVlSIHMK24Aq2S4biC eYhiH5/rhv6/RBZQkwx/LHNjyoc1J7ea3taqvhNYt4FzPwD+Fy7NbZ3c6XdxbsTvxGso GVWYlUdeB1tFBIIqZ/NhUXjds9Q2I/bBbPlWcbw0gVnmQ/wo/mBIJMYOa+z+DvanBUVN yX3Nzp/DH3/Fkid0mc5EdKvidjNnYZL/bF+nwIGnmVqKynIOcZMKxU6Lu1FYfmCtZJtK O42w== X-Gm-Message-State: AOAM530gRxUCiIclRq760/oOxPRluCn9VckMXvXjz4EqrNWBnibOMcRT mxtKcJVdrDyiUhCjXYbxfHIuyFx2R+67LYco X-Google-Smtp-Source: ABdhPJztlyDnxqW+tCluo1zQcHISh9MRheAbpgrcjhVfg6uiLIQBqjzru7wLvoT5T/oLsbWRseVQ28oyUeghjYDF X-Received: from andreyknvl3.muc.corp.google.com ([2a00:79e0:15:13:7220:84ff:fe09:7e9d]) (user=andreyknvl job=sendgmr) by 2002:a25:ac1f:: with SMTP id w31mr4193358ybi.87.1610553817007; Wed, 13 Jan 2021 08:03:37 -0800 (PST) Date: Wed, 13 Jan 2021 17:03:29 +0100 In-Reply-To: Message-Id: <7fbac00e4d155cf529517a165a48351dcf3c3156.1610553774.git.andreyknvl@google.com> Mime-Version: 1.0 References: X-Mailer: git-send-email 2.30.0.284.gd98b1dd5eaa7-goog Subject: [PATCH 1/2] kasan, mm: fix conflicts with init_on_alloc/free From: Andrey Konovalov To: Catalin Marinas , Vincenzo Frascino , Dmitry Vyukov , Alexander Potapenko , Marco Elver Cc: Andrew Morton , Will Deacon , Andrey Ryabinin , Peter Collingbourne , Evgenii Stepanov , Branislav Rankov , Kevin Brodsky , kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrey Konovalov Content-Type: text/plain; charset="UTF-8" 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: 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. Link: https://linux-review.googlesource.com/id/I50dd32838a666e173fe06c3c5c766f2c36aae901 Fixes: aa1ef4d7b3f67 ("kasan, mm: reset tags when accessing metadata") Reported-by: Dmitry Vyukov Signed-off-by: Andrey Konovalov --- mm/slub.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index dc5b42e700b8..75fb097d990d 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2791,7 +2791,8 @@ static __always_inline void maybe_wipe_obj_freeptr(struct kmem_cache *s, 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 @@ static __always_inline void *slab_alloc_node(struct kmem_cache *s, 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_cache *s, gfp_t flags, size_t size, 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 */ -- 2.30.0.284.gd98b1dd5eaa7-goog