From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:50156 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405997AbeHATIk (ORCPT ); Wed, 1 Aug 2018 15:08:40 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sahitya Tummala , Chao Yu , Jaegeuk Kim , Sasha Levin Subject: [PATCH 4.14 059/246] f2fs: Fix deadlock in shutdown ioctl Date: Wed, 1 Aug 2018 18:49:29 +0200 Message-Id: <20180801165014.533785261@linuxfoundation.org> In-Reply-To: <20180801165011.700991984@linuxfoundation.org> References: <20180801165011.700991984@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sahitya Tummala [ Upstream commit 60b2b4ee2bc01dd052f99fa9d65da2232102ef8e ] f2fs_ioc_shutdown() ioctl gets stuck in the below path when issued with F2FS_GOING_DOWN_FULLSYNC option. __switch_to+0x90/0xc4 percpu_down_write+0x8c/0xc0 freeze_super+0xec/0x1e4 freeze_bdev+0xc4/0xcc f2fs_ioctl+0xc0c/0x1ce0 f2fs_compat_ioctl+0x98/0x1f0 Signed-off-by: Sahitya Tummala Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/f2fs/file.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1808,9 +1808,11 @@ static int f2fs_ioc_shutdown(struct file if (get_user(in, (__u32 __user *)arg)) return -EFAULT; - ret = mnt_want_write_file(filp); - if (ret) - return ret; + if (in != F2FS_GOING_DOWN_FULLSYNC) { + ret = mnt_want_write_file(filp); + if (ret) + return ret; + } switch (in) { case F2FS_GOING_DOWN_FULLSYNC: @@ -1838,7 +1840,8 @@ static int f2fs_ioc_shutdown(struct file } f2fs_update_time(sbi, REQ_TIME); out: - mnt_drop_write_file(filp); + if (in != F2FS_GOING_DOWN_FULLSYNC) + mnt_drop_write_file(filp); return ret; }