| From 08b63b7f022f50c88587dfc9dd707dfee2d32730 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Sun, 6 Oct 2019 17:57:54 -0700 |
| Subject: fs: ocfs2: fix a possible null-pointer dereference in |
| ocfs2_write_end_nolock() |
| |
| From: Jia-Ju Bai <baijiaju1990@gmail.com> |
| |
| [ Upstream commit 583fee3e12df0e6f1f66f063b989d8e7fed0e65a ] |
| |
| In ocfs2_write_end_nolock(), there are an if statement on lines 1976, |
| 2047 and 2058, to check whether handle is NULL: |
| |
| if (handle) |
| |
| When handle is NULL, it is used on line 2045: |
| |
| ocfs2_update_inode_fsync_trans(handle, inode, 1); |
| oi->i_sync_tid = handle->h_transaction->t_tid; |
| |
| Thus, a possible null-pointer dereference may occur. |
| |
| To fix this bug, handle is checked before calling |
| ocfs2_update_inode_fsync_trans(). |
| |
| This bug is found by a static analysis tool STCheck written by us. |
| |
| Link: http://lkml.kernel.org/r/20190726033705.32307-1-baijiaju1990@gmail.com |
| Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> |
| Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> |
| Cc: Mark Fasheh <mark@fasheh.com> |
| Cc: Joel Becker <jlbec@evilplan.org> |
| Cc: Junxiao Bi <junxiao.bi@oracle.com> |
| Cc: Changwei Ge <gechangwei@live.cn> |
| Cc: Gang He <ghe@suse.com> |
| Cc: Jun Piao <piaojun@huawei.com> |
| Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
| Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| fs/ocfs2/aops.c | 3 ++- |
| 1 file changed, 2 insertions(+), 1 deletion(-) |
| |
| diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c |
| index ebeec7530cb60..7de0c9562b707 100644 |
| --- a/fs/ocfs2/aops.c |
| +++ b/fs/ocfs2/aops.c |
| @@ -2054,7 +2054,8 @@ out_write_size: |
| inode->i_mtime = inode->i_ctime = current_time(inode); |
| di->i_mtime = di->i_ctime = cpu_to_le64(inode->i_mtime.tv_sec); |
| di->i_mtime_nsec = di->i_ctime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec); |
| - ocfs2_update_inode_fsync_trans(handle, inode, 1); |
| + if (handle) |
| + ocfs2_update_inode_fsync_trans(handle, inode, 1); |
| } |
| if (handle) |
| ocfs2_journal_dirty(handle, wc->w_di_bh); |
| -- |
| 2.20.1 |
| |