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=unavailable 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 73440C4332E for ; Thu, 19 Mar 2020 11:58:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 56A2720722 for ; Thu, 19 Mar 2020 11:58:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727195AbgCSL60 (ORCPT ); Thu, 19 Mar 2020 07:58:26 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:48422 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726785AbgCSL60 (ORCPT ); Thu, 19 Mar 2020 07:58:26 -0400 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 9D11378D7C42C01D85C1; Thu, 19 Mar 2020 19:58:10 +0800 (CST) Received: from szvp000203569.huawei.com (10.120.216.130) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.487.0; Thu, 19 Mar 2020 19:58:04 +0800 From: Chao Yu To: CC: , , , Chao Yu Subject: [PATCH 4/4] f2fs: fix NULL pointer dereference in f2fs_write_begin() Date: Thu, 19 Mar 2020 19:58:00 +0800 Message-ID: <20200319115800.108926-4-yuchao0@huawei.com> X-Mailer: git-send-email 2.18.0.rc1 In-Reply-To: <20200319115800.108926-1-yuchao0@huawei.com> References: <20200319115800.108926-1-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 BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:f2fs_write_begin+0x823/0xb90 [f2fs] Call Trace: f2fs_quota_write+0x139/0x1d0 [f2fs] write_blk+0x36/0x80 [quota_tree] get_free_dqblk+0x42/0xa0 [quota_tree] do_insert_tree+0x235/0x4a0 [quota_tree] do_insert_tree+0x26e/0x4a0 [quota_tree] do_insert_tree+0x26e/0x4a0 [quota_tree] do_insert_tree+0x26e/0x4a0 [quota_tree] qtree_write_dquot+0x70/0x190 [quota_tree] v2_write_dquot+0x43/0x90 [quota_v2] dquot_acquire+0x77/0x100 f2fs_dquot_acquire+0x2f/0x60 [f2fs] dqget+0x310/0x450 dquot_transfer+0x7e/0x120 f2fs_setattr+0x11a/0x4a0 [f2fs] notify_change+0x349/0x480 chown_common+0x168/0x1c0 do_fchownat+0xbc/0xf0 __x64_sys_fchownat+0x20/0x30 do_syscall_64+0x5f/0x220 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Passing fsdata parameter to .write_{begin,end} in f2fs_quota_write(), so that if quota file is compressed one, we can avoid above NULL pointer dereference when updating quota content. Signed-off-by: Chao Yu --- fs/f2fs/super.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index ebffe7aa08ee..b83b17b54a0a 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -1936,6 +1936,7 @@ static ssize_t f2fs_quota_write(struct super_block *sb, int type, int offset = off & (sb->s_blocksize - 1); size_t towrite = len; struct page *page; + void *fsdata = NULL; char *kaddr; int err = 0; int tocopy; @@ -1945,7 +1946,7 @@ static ssize_t f2fs_quota_write(struct super_block *sb, int type, towrite); retry: err = a_ops->write_begin(NULL, mapping, off, tocopy, 0, - &page, NULL); + &page, &fsdata); if (unlikely(err)) { if (err == -ENOMEM) { congestion_wait(BLK_RW_ASYNC, @@ -1962,7 +1963,7 @@ static ssize_t f2fs_quota_write(struct super_block *sb, int type, flush_dcache_page(page); a_ops->write_end(NULL, mapping, off, tocopy, tocopy, - page, NULL); + page, fsdata); offset = 0; towrite -= tocopy; off += tocopy; -- 2.18.0.rc1