[PATCH 4.9 097/101] f2fs: fix missing up_read

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>

commit 89d13c38501df730cbb2e02c4499da1b5187119d upstream.

This patch fixes missing up_read call.

Fixes: c9b60788fc76 ("f2fs: fix to do sanity check with block address in main area")
Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 fs/f2fs/node.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1606,8 +1606,10 @@ static int f2fs_write_node_page(struct p
 	}
 
 	if (__is_valid_data_blkaddr(ni.blk_addr) &&
-		!f2fs_is_valid_blkaddr(sbi, ni.blk_addr, DATA_GENERIC))
+		!f2fs_is_valid_blkaddr(sbi, ni.blk_addr, DATA_GENERIC)) {
+		up_read(&sbi->node_write);
 		goto redirty_out;
+	}
 
 	set_page_writeback(page);
 	fio.old_blkaddr = ni.blk_addr;