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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0494DC001B2 for ; Fri, 16 Dec 2022 07:42:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229774AbiLPHmn (ORCPT ); Fri, 16 Dec 2022 02:42:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52766 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229627AbiLPHmk (ORCPT ); Fri, 16 Dec 2022 02:42:40 -0500 Received: from mail-pj1-x102c.google.com (mail-pj1-x102c.google.com [IPv6:2607:f8b0:4864:20::102c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CBCD73E0B5 for ; Thu, 15 Dec 2022 23:42:39 -0800 (PST) Received: by mail-pj1-x102c.google.com with SMTP id k88-20020a17090a4ce100b00219d0b857bcso1606555pjh.1 for ; Thu, 15 Dec 2022 23:42:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=p11g1cwrNZTNPGZ9JOLQCCww3AgSudE2cVlNLnF16zc=; b=ixvI7Ak3I75fySctV1/dd+sdZTABsHg8bu7hFpLuyN8BHKmGfN3z1Aj/0VKzeMjcv3 Yx2YarpUotQqLooLXd7KrsAYxed3b55Q1KiMlbqTzvob8qcVCsK4zQv+5Jyj4Zzc3r5R SHdVgW2Siaz+bwQ8R8ziN5juuRyjNlYJzZHVeLs32oSEmmAh+UXapL/LWJIyI5s0S4fX mj0d3kfvEgX5Ts3EP3qykq2Jed42QJgR8LHUdIpi1rK1iaXOOskmnLea0OKLq37aB//X jd7hMaXbMb6TNspCjwIS3MoZWBqbBaiX9mtaUuYsEq3QpMKStj/9nSxpeMRa6cW/hSzo Ndkg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=p11g1cwrNZTNPGZ9JOLQCCww3AgSudE2cVlNLnF16zc=; b=F0BJE9kw9EqkmaXCDHk5cGA0z0ykuOk5ZFLZdN9qIIjHbGiKBTjETzCz834D18B/Bl opKXkE+Tf2xYuE4VGekl47L+qzmGAFn3cdExCHO1Prjv+CbvPKM9zn07dh5WqHYcKSWs 894tHzAoEWHnEIH53RhLkqZtMBqcM/13SwbX22E6z8PpOoLyPjy9Ltnz5Jk+p9rGEH7u TyWaxIyuOQmo08Bj0DjCJV5Xxiw2x6r93MK2/33EibT/uBDPqoeYTT0Km/M6j6OGun0K M4/8fLWkZWL3aC2AG9ITZNQOOJJGvm7L0glCQCOPNcca8mj8pdmOErVzzjt/0gtY+dfW T0MA== X-Gm-Message-State: ANoB5pkDM7pKAq6M6TyJ3mzjp30Mx0OP18UuQKPisyn5Y7ycI+pT99kC 09GKfsmwWb3E88Qvp72lDW0= X-Google-Smtp-Source: AA0mqf45G+6k9iUrkTKEigJA7PtUlWdNG+akMhT77GtTrdF0p5ErbSlUKD9wC544JLf8+PzblnM7nQ== X-Received: by 2002:a05:6a20:65a1:b0:aa:7eab:25a5 with SMTP id p33-20020a056a2065a100b000aa7eab25a5mr34541260pzh.34.1671176559146; Thu, 15 Dec 2022 23:42:39 -0800 (PST) Received: from hyeyoo ([114.29.91.56]) by smtp.gmail.com with ESMTPSA id c9-20020a170903234900b001885041d7b8sm854453plh.293.2022.12.15.23.42.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 15 Dec 2022 23:42:38 -0800 (PST) Date: Fri, 16 Dec 2022 16:42:32 +0900 From: Hyeonggon Yoo <42.hyeyoo@gmail.com> To: Chen Jun Cc: cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, vbabka@suse.cz, roman.gushchin@linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org, xuqiang36@huawei.com Subject: Re: [PATCH] mm, slub: fix uninitialized variable in __slab_free Message-ID: References: <20221216033119.14159-1-chenjun102@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221216033119.14159-1-chenjun102@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 16, 2022 at 03:31:19AM +0000, Chen Jun wrote: > new.frozen is not initialized before it is used. > > Fixes: 2cfb7455d223 ("slub: Rework allocator fastpaths") > Signed-off-by: Chen Jun > --- > mm/slub.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/mm/slub.c b/mm/slub.c > index 13459c69095a..8628c88875b6 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -3593,6 +3593,7 @@ static void __slab_free(struct kmem_cache *s, struct slab *slab, > return; > } > > + new.frozen = 0; > do { > if (unlikely(n)) { > spin_unlock_irqrestore(&n->list_lock, flags); > -- > 2.17.1 This is incorrect because new.frozen is initialized when new.counters is initialized. See definition of struct slab in mm/slab.h: struct slab { [...] union { unsigned long counters; struct { unsigned inuse:16; unsigned objects:15; unsigned frozen:1; }; }; } -- Thanks, Hyeonggon