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 B8A3BC4332F for ; Thu, 10 Nov 2022 11:02:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230389AbiKJLCK (ORCPT ); Thu, 10 Nov 2022 06:02:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50672 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230382AbiKJLBy (ORCPT ); Thu, 10 Nov 2022 06:01:54 -0500 Received: from mail-yw1-x1131.google.com (mail-yw1-x1131.google.com [IPv6:2607:f8b0:4864:20::1131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 206766C71C for ; Thu, 10 Nov 2022 03:01:51 -0800 (PST) Received: by mail-yw1-x1131.google.com with SMTP id 00721157ae682-370547b8ca0so12389447b3.0 for ; Thu, 10 Nov 2022 03:01:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=bmHpbHS5doLrhzAjJPWJ0TWG+6ktMdA7UyRQfP5yVLQ=; b=PLbZrq9bLdievV0a3Mb3BaXEmA0lIlXEss9RAzy1kIWFQcyoX58mVA9H25RToeQszv 5YvjuWvLH/5NrA6TyG40gt3N0kKc23/A76AT88SS5ZTAe2T4n9e5jWLXGZpGYLIXjEqQ Khc8dLGZ8N7MaH3FLaoh08tpHLRjoS7QxA8kr5/5fJgId7Xy8vZ/wOwRGZwr9f6d4282 +pnfoWEXAiSc54Zb5MGIncElzoGgObabXLveU3e1AC2ar9FWmubdTRQJwgj+eSJ1gRxV gbiBAeXoiiYsuVJihJyxE1Ps8zJ7mYhKmo3OErMbadxuKY3GcSaJWPGlaCt1AsgWghiJ V5xQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=bmHpbHS5doLrhzAjJPWJ0TWG+6ktMdA7UyRQfP5yVLQ=; b=ylbhNigC1YgHXL5lWvehp6Hg4CItJuOfwPD16Xohzw3Nox30usP9xV76rBj+Re2S1H BxJ22UyQ0N0ijrB6TLdvnTMZcm8usp7EZNpC3HUeHsT7nWsPQDuGUleDJu0ocxJnL/R6 rpadoT42StlBUq1PsW9yBkjU4wu1ksezh8RZTK4GOGx94SbOnENgHU5hHOUF4Ox+tlUu Gh6M482tNmrRbEQvKWaJbor7uJwgUUTGCc5jIx9rPV8BbAX6rP0dSu8EjGDVwA8AIqAd SI2QwYhc2JaW6Xdt5/zs87vdVMgfV5FFMianWZfsrEmb/59ZsSQFXKteDPMK50Zfh2sq s/5Q== X-Gm-Message-State: ACrzQf0zEzVN3KLG34Wo6PVcAar0KFjWCAqsdCunrVMAYSxN2wMRgJY2 SE7w6TYbu5tSM2n7HmRuCCADRVYE91Xjf0vBZi2eiQ== X-Google-Smtp-Source: AMsMyM4R1yv3ctd1jPaIemb0nxA+rY5vVqfKSKgK+YNO+lpbSGR7xqL6G42PREeei1JWOBTJSsRAC/uEYrLUaBmIUU0= X-Received: by 2002:a0d:da03:0:b0:368:5712:5795 with SMTP id c3-20020a0dda03000000b0036857125795mr61929838ywe.428.1668078109722; Thu, 10 Nov 2022 03:01:49 -0800 (PST) MIME-Version: 1.0 References: <00000000000058d01705ecddccb0@google.com> In-Reply-To: From: Alexander Potapenko Date: Thu, 10 Nov 2022 12:01:13 +0100 Message-ID: Subject: Re: [syzbot] KMSAN: uninit-value in pagecache_write To: Eric Biggers Cc: syzbot , adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tytso@mit.edu Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 8, 2022 at 6:41 PM Eric Biggers wrote: > > On Tue, Nov 08, 2022 at 10:08:36AM +0100, 'Alexander Potapenko' via syzka= ller-bugs wrote: > > > > > > > > Anyway, this patch doesn't hurt, I suppose. Can please you send it= out as a > > > > formal patch to linux-ext4? It would be easy for people to miss th= is patch > > > > buried in this thread. Also, can you please send a patch to linux-= f2fs-devel > > > > for the same code in fs/f2fs/verity.c? > > > > > > Will do! > > > > Shall I also initialize fsdata here: > > > > $ git grep 'void \*fsdata;' > > fs/affs/file.c: void *fsdata; > > fs/ext4/verity.c: void *fsdata; > > fs/f2fs/verity.c: void *fsdata; > > fs/hfs/extent.c: void *fsdata; > > fs/hfsplus/extents.c: void *fsdata; > > fs/ocfs2/mmap.c: void *fsdata; > > Yes, it looks like they all need this. Except maybe ocfs2? It's hard to= tell. For ocfs2 the begin/end functions are always the same, so it's harder to mess fsdata up. Guess we can say for now that __ocfs2_page_mkwrite() never passes an uninitialized variable to another function. > - Eric --=20 Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Stra=C3=9Fe, 33 80636 M=C3=BCnchen Gesch=C3=A4ftsf=C3=BChrer: Paul Manicle, Liana Sebastian Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg