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 3e0a93e799ea1..9b827143a3504 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -2042,7 +2042,8 @@ int ocfs2_write_end_nolock(struct address_space *mapping, 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);