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 7B037ECAAD8 for ; Mon, 19 Sep 2022 01:35:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229682AbiISBfS (ORCPT ); Sun, 18 Sep 2022 21:35:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37842 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229483AbiISBfP (ORCPT ); Sun, 18 Sep 2022 21:35:15 -0400 Received: from mail-pj1-x1030.google.com (mail-pj1-x1030.google.com [IPv6:2607:f8b0:4864:20::1030]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5387CE089 for ; Sun, 18 Sep 2022 18:35:12 -0700 (PDT) Received: by mail-pj1-x1030.google.com with SMTP id go6so22120720pjb.2 for ; Sun, 18 Sep 2022 18:35:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:from:to:cc:subject:date; bh=N8eqqewSNmFIl18uGjm9/zwnlUkZ2Q0UubEd4wLISog=; b=VwTS/iD32l18B+pXNDm5P9ZD7eMFp3vlJSuYaDdUPeMCzLhQhs/JW2ONtw3Q1opXD+ I40OrHfOKTnrKAUE1loXBWZO+JGcdVA7OmXCKEimDHHimhVvAVyB9Yl+kECFQgRxyf7g SGINgLLmK8IMTm/lCy30VpdNramxoJtCwpGevCIujBagUt7koRlyMbu4m8jXTcJCC155 cESv0n5Wdu6HCyvbfLMk6KhdV6Oh2ZGPnY+oSJV7+Sgs3SrbkGyjq8p0m4POIyJm0w4x 6up2jG4lOk4Ipm0ofExSwhwmPg88SShlFEiY/H6nfMdyjF6u+JJvFQXd70PjDvBz4TRM g3xA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:x-gm-message-state:from:to:cc :subject:date; bh=N8eqqewSNmFIl18uGjm9/zwnlUkZ2Q0UubEd4wLISog=; b=avaZGOrkIBJe7MwdwpIMzbEiN0P2Q1BJdinw/I9FQ19TuPs+nGpOCgBcM2BQyqScty DIGwUVZfMqRqllJZNyWSVmTa9LZz3qfEd/NUJsVkveqlkLfgkRCL/ziI7Ie3rJtLIFpu duGT5UDvlGrMd9tsAkYydS2lJBuJdcAfJrlLFHGpAXJrz6BK9PGUOszhXFy94oV3NkjQ YfvX07bH7FknQKSs8zVYmr5ptYV15om9Y6d/OhayM710fVWoehna9SAEuGyICIyz43+o eFQFiXGM0S+2VTL/5tT7TNmuNs5TwtjTbzmFlBG/g09uSIX2tTkaOPHfwA3B8M43k9/u DI3A== X-Gm-Message-State: ACrzQf2WvANXEcCAoDgd6+W3okzFB0qUNBQFoXLehlq4PIkRL96BRkQP WGgGoQ33zuU3XbZ6yhaUfMA= X-Google-Smtp-Source: AMsMyM7lvEM+F5KGX5dk+CXMe09P0qpCz6hXV6oKU7UGjQPmGeo6vkBsjnZ8m1oqiBhixFIlsEMQ8g== X-Received: by 2002:a17:903:2290:b0:178:48b6:f57c with SMTP id b16-20020a170903229000b0017848b6f57cmr10663601plh.78.1663551311817; Sun, 18 Sep 2022 18:35:11 -0700 (PDT) Received: from localhost ([156.236.96.165]) by smtp.gmail.com with ESMTPSA id a5-20020aa794a5000000b00543a098a6ffsm15837530pfl.212.2022.09.18.18.35.10 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Sun, 18 Sep 2022 18:35:11 -0700 (PDT) Date: Mon, 19 Sep 2022 09:37:47 +0800 From: Yue Hu To: Gao Xiang Cc: linux-erofs@lists.ozlabs.org, syzbot+f966c13b1b4fc0403b19@syzkaller.appspotmail.com, syzkaller-bugs , LKML Subject: Re: [PATCH] erofs: fix order >= MAX_ORDER warning due to crafted nagative i_size Message-ID: <20220919093747.00005bd6.zbestahu@gmail.com> In-Reply-To: <20220909023948.28925-1-hsiangkao@linux.alibaba.com> References: <000000000000ac8efa05e7feaa1f@google.com> <20220909023948.28925-1-hsiangkao@linux.alibaba.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; i686-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 9 Sep 2022 10:39:48 +0800 Gao Xiang wrote: > As syzbot reported [1], the root cause is that i_size field is a > signed type, and negative i_size is also less than EROFS_BLKSIZ. > As a consequence, it's handled as fast symlink unexpectedly. > > Let's fall back to the generic path to deal with such unusual i_size. > > [1] https://lore.kernel.org/r/000000000000ac8efa05e7feaa1f@google.com > Reported-by: syzbot+f966c13b1b4fc0403b19@syzkaller.appspotmail.com > Fixes: 431339ba9042 ("staging: erofs: add inode operations") > Signed-off-by: Gao Xiang > --- > fs/erofs/inode.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c > index 95a403720e8c..16cf9a283557 100644 > --- a/fs/erofs/inode.c > +++ b/fs/erofs/inode.c > @@ -214,7 +214,7 @@ static int erofs_fill_symlink(struct inode *inode, void *kaddr, > > /* if it cannot be handled with fast symlink scheme */ > if (vi->datalayout != EROFS_INODE_FLAT_INLINE || > - inode->i_size >= EROFS_BLKSIZ) { > + inode->i_size >= EROFS_BLKSIZ || inode->i_size < 0) { Reviewed-by: Yue Hu > inode->i_op = &erofs_symlink_iops; > return 0; > }