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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 1422BC11D31 for ; Mon, 24 Feb 2020 11:20:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DD8AA20828 for ; Mon, 24 Feb 2020 11:20:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727584AbgBXLUn (ORCPT ); Mon, 24 Feb 2020 06:20:43 -0500 Received: from szxga05-in.huawei.com ([45.249.212.191]:10682 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727498AbgBXLUl (ORCPT ); Mon, 24 Feb 2020 06:20:41 -0500 Received: from DGGEMS413-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id A75C4EE6E982B2D97FEB; Mon, 24 Feb 2020 19:20:36 +0800 (CST) Received: from szvp000203569.huawei.com (10.120.216.130) by DGGEMS413-HUB.china.huawei.com (10.3.19.213) with Microsoft SMTP Server id 14.3.439.0; Mon, 24 Feb 2020 19:20:27 +0800 From: Chao Yu To: CC: , , , Chao Yu Subject: [PATCH 3/5] f2fs: fix to avoid NULL pointer dereference Date: Mon, 24 Feb 2020 19:20:17 +0800 Message-ID: <20200224112019.93829-3-yuchao0@huawei.com> X-Mailer: git-send-email 2.18.0.rc1 In-Reply-To: <20200224112019.93829-1-yuchao0@huawei.com> References: <20200224112019.93829-1-yuchao0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.120.216.130] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Unable to handle kernel NULL pointer dereference at virtual address 00000000 PC is at f2fs_free_dic+0x60/0x2c8 LR is at f2fs_decompress_pages+0x3c4/0x3e8 f2fs_free_dic+0x60/0x2c8 f2fs_decompress_pages+0x3c4/0x3e8 __read_end_io+0x78/0x19c f2fs_post_read_work+0x6c/0x94 process_one_work+0x210/0x48c worker_thread+0x2e8/0x44c kthread+0x110/0x120 ret_from_fork+0x10/0x18 In f2fs_free_dic(), we can not use f2fs_put_page(,1) to release dic->tpages[i], as the page's mapping is NULL. Signed-off-by: Chao Yu --- fs/f2fs/compress.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c index 4ba65a3b0456..864035549329 100644 --- a/fs/f2fs/compress.c +++ b/fs/f2fs/compress.c @@ -1133,7 +1133,8 @@ void f2fs_free_dic(struct decompress_io_ctx *dic) for (i = 0; i < dic->cluster_size; i++) { if (dic->rpages[i]) continue; - f2fs_put_page(dic->tpages[i], 1); + unlock_page(dic->tpages[i]); + put_page(dic->tpages[i]); } kfree(dic->tpages); } -- 2.18.0.rc1