f2fs: fix encrypted page memory leak

For IPU path of f2fs_do_write_data_page(), in its error path, we
need to release encrypted page and fscrypt context, otherwise it
will cause memory leak.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/data.c

@@ -1861,8 +1861,13 @@ int f2fs_do_write_data_page(struct f2fs_io_info *fio)
 		if (fio->need_lock == LOCK_REQ)
 			f2fs_unlock_op(fio->sbi);
 		err = f2fs_inplace_write_data(fio);
-		if (err && PageWriteback(page))
+		if (err) {
+			if (f2fs_encrypted_file(inode))
+				fscrypt_pullback_bio_page(&fio->encrypted_page,
+									true);
+			if (PageWriteback(page))
 				end_page_writeback(page);
+		}
 		trace_f2fs_do_write_data_page(fio->page, IPU);
 		set_inode_flag(inode, FI_UPDATE_WRITE);
 		return err;