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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B45E2ECAAD5 for ; Fri, 9 Sep 2022 02:40:13 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4MP0b01vp4z3bZP for ; Fri, 9 Sep 2022 12:40:12 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.alibaba.com (client-ip=115.124.30.42; helo=out30-42.freemail.mail.aliyun.com; envelope-from=hsiangkao@linux.alibaba.com; receiver=) Received: from out30-42.freemail.mail.aliyun.com (out30-42.freemail.mail.aliyun.com [115.124.30.42]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4MP0Zs69gWz2xG9 for ; Fri, 9 Sep 2022 12:40:04 +1000 (AEST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R141e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045176;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0VP7M4tU_1662691196; Received: from e18g06460.et15sqa.tbsite.net(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0VP7M4tU_1662691196) by smtp.aliyun-inc.com; Fri, 09 Sep 2022 10:40:01 +0800 From: Gao Xiang To: linux-erofs@lists.ozlabs.org Subject: [PATCH] erofs: fix order >= MAX_ORDER warning due to crafted nagative i_size Date: Fri, 9 Sep 2022 10:39:48 +0800 Message-Id: <20220909023948.28925-1-hsiangkao@linux.alibaba.com> X-Mailer: git-send-email 2.24.4 In-Reply-To: <000000000000ac8efa05e7feaa1f@google.com> References: <000000000000ac8efa05e7feaa1f@google.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Gao Xiang , syzbot+f966c13b1b4fc0403b19@syzkaller.appspotmail.com, syzkaller-bugs , LKML Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" 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) { inode->i_op = &erofs_symlink_iops; return 0; } -- 2.24.4