ksmbd: don't align last entry offset in smb2 query directory

[ Upstream commit 04e2609 ]

When checking smb2 query directory packets from other servers,
OutputBufferLength is different with ksmbd. Other servers add an unaligned
next offset to OutputBufferLength for the last entry.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

fs/ksmbd/smb2pdu.c

@@ -3423,9 +3423,9 @@ static int smb2_populate_readdir_entry(struct ksmbd_conn *conn, int info_level,
 		goto free_conv_name;
 	}
 
-	struct_sz = readdir_info_level_struct_sz(info_level);
-	next_entry_offset = ALIGN(struct_sz - 1 + conv_len,
-				  KSMBD_DIR_INFO_ALIGNMENT);
+	struct_sz = readdir_info_level_struct_sz(info_level) - 1 + conv_len;
+	next_entry_offset = ALIGN(struct_sz, KSMBD_DIR_INFO_ALIGNMENT);
+	d_info->last_entry_off_align = next_entry_offset - struct_sz;
 
 	if (next_entry_offset > d_info->out_buf_len) {
 		d_info->out_buf_len = 0;
@@ -3977,6 +3977,7 @@ int smb2_query_dir(struct ksmbd_work *work)
 		((struct file_directory_info *)
 		((char *)rsp->Buffer + d_info.last_entry_offset))
 		->NextEntryOffset = 0;
+		d_info.data_count -= d_info.last_entry_off_align;
 
 		rsp->StructureSize = cpu_to_le16(9);
 		rsp->OutputBufferOffset = cpu_to_le16(72);

fs/ksmbd/vfs.h

@@ -47,6 +47,7 @@ struct ksmbd_dir_info {
 	int		last_entry_offset;
 	bool		hide_dot_file;
 	int		flags;
+	int		last_entry_off_align;
 };
 
 struct ksmbd_readdir_data {