[PATCH] f2fs: fix to avoid accessing uninitialized field of inode page in is_alive()

[Chao Yu]

If inode is newly created, inode page may not synchronize with inode cache,
so fields like .i_inline or .i_extra_isize could be wrong, in below call
path, we may access such wrong fields, result in failing to migrate valid
target block.

- gc_data_segment
 - is_alive
  - datablock_addr
   - offset_in_addr

Fixes: 7a2af766af15 ("f2fs: enhance on-disk inode structure scalability")
Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
 fs/f2fs/dir.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 765f13354d3f..b1840852967e 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -479,6 +479,9 @@ struct page *f2fs_init_inode_metadata(struct inode *inode, struct inode *dir,
 		if (IS_ERR(page))
 			return page;
 
+		/* synchronize inode page's data from inode cache */
+		f2fs_update_inode(inode, page);
+
 		if (S_ISDIR(inode->i_mode)) {
 			/* in order to handle error case */
 			get_page(page);
-- 
2.18.0.rc1