From patchwork Sat Jan 16 09:09:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miaohe Lin X-Patchwork-Id: 12024729 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 257ADC433DB for ; Sat, 16 Jan 2021 09:09:32 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 74A0E23A59 for ; Sat, 16 Jan 2021 09:09:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 74A0E23A59 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 9FC3D6B010A; Sat, 16 Jan 2021 04:09:30 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 9856C6B010F; Sat, 16 Jan 2021 04:09:30 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 874648D0200; Sat, 16 Jan 2021 04:09:30 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0065.hostedemail.com [216.40.44.65]) by kanga.kvack.org (Postfix) with ESMTP id 6D4D06B010A for ; Sat, 16 Jan 2021 04:09:30 -0500 (EST) Received: from smtpin17.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 38D0C180AD801 for ; Sat, 16 Jan 2021 09:09:30 +0000 (UTC) X-FDA: 77711064900.17.badge56_320944a27536 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin17.hostedemail.com (Postfix) with ESMTP id 18EBF180D078C for ; Sat, 16 Jan 2021 09:09:30 +0000 (UTC) X-HE-Tag: badge56_320944a27536 X-Filterd-Recvd-Size: 2421 Received: from szxga05-in.huawei.com (szxga05-in.huawei.com [45.249.212.191]) by imf50.hostedemail.com (Postfix) with ESMTP for ; Sat, 16 Jan 2021 09:09:28 +0000 (UTC) Received: from DGGEMS401-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4DHsdt1dXvzMGdM; Sat, 16 Jan 2021 17:08:02 +0800 (CST) Received: from huawei.com (10.175.104.175) by DGGEMS401-HUB.china.huawei.com (10.3.19.201) with Microsoft SMTP Server id 14.3.498.0; Sat, 16 Jan 2021 17:09:12 +0800 From: Miaohe Lin To: CC: , , Subject: [PATCH] hugetlbfs: make BUG_ON(!inode) takes effect in hugetlbfs_setattr Date: Sat, 16 Jan 2021 04:09:10 -0500 Message-ID: <20210116090910.5671-1-linmiaohe@huawei.com> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 X-Originating-IP: [10.175.104.175] X-CFilter-Loop: Reflected 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: When we reach here with inode = NULL, we should have crashed as inode has already been dereferenced via hstate_inode. In order to make BUG_ON(!inode) takes effect, we should defer initializing hstate until we really need it. Also do this for hugetlbfs_inode_info as it's only used when ia_valid is verified with ATTR_SIZE. Signed-off-by: Miaohe Lin --- fs/hugetlbfs/inode.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 740693d7f255..9b221b87fbea 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -755,10 +755,8 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset, static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr) { struct inode *inode = d_inode(dentry); - struct hstate *h = hstate_inode(inode); int error; unsigned int ia_valid = attr->ia_valid; - struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode); BUG_ON(!inode); @@ -767,6 +765,8 @@ static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr) return error; if (ia_valid & ATTR_SIZE) { + struct hstate *h = hstate_inode(inode); + struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode); loff_t oldsize = inode->i_size; loff_t newsize = attr->ia_size;