Merge tag '6.0-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cfis fixes from Steve French:

 - two locking fixes (zero range, punch hole)

 - DFS 9 fix (padding), affecting some servers

 - three minor cleanup changes

* tag '6.0-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: Add helper function to check smb1+ server
  cifs: Use help macro to get the mid header size
  cifs: Use help macro to get the header preamble size
  cifs: skip extra NULL byte in filenames
  smb3: missing inode locks in punch hole
  smb3: missing inode locks in zero range

1 files changed, 6 insertions, 10 deletions

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 91cfc5b47ac7..128e44e57528 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -2572,19 +2572,15 @@ alloc_path_with_tree_prefix(__le16 **out_path, int *out_size, int *out_len,
 
 	path_len = UniStrnlen((wchar_t *)path, PATH_MAX);
 
-	/*
-	 * make room for one path separator between the treename and
-	 * path
-	 */
-	*out_len = treename_len + 1 + path_len;
+	/* make room for one path separator only if @path isn't empty */
+	*out_len = treename_len + (path[0] ? 1 : 0) + path_len;
 
 	/*
-	 * final path needs to be null-terminated UTF16 with a
-	 * size aligned to 8
+	 * final path needs to be 8-byte aligned as specified in
+	 * MS-SMB2 2.2.13 SMB2 CREATE Request.
 	 */
-
-	*out_size = roundup((*out_len+1)*2, 8);
-	*out_path = kzalloc(*out_size, GFP_KERNEL);
+	*out_size = roundup(*out_len * sizeof(__le16), 8);
+	*out_path = kzalloc(*out_size + sizeof(__le16) /* null */, GFP_KERNEL);
 	if (!*out_path)
 		return -ENOMEM;