CIFS: Allow reset of file to ATTR_NORMAL when archive bit not set

[CIFS] Allow reset of file to ATTR_NORMAL when archive bit not set

When a file had a dos attribute of 0x1 (readonly - but dos attribute
of archive was not set) - doing chmod 0777 or equivalent would
try to set a dos attribute of 0 (which some servers ignore)
rather than ATTR_NORMAL (0x20) which most servers accept.
Does not affect servers which support the CIFS Unix Extensions.

[<cebbert@redhat.com>: removed changelog part of patch]

Cc: Chuck Ebbert <cebbert@redhat.com>
Acked-by: Prasad Potluri <pvp@us.ibm.com>
Acked-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

fs/cifs/inode.c

@@ -1133,6 +1133,7 @@ int cifs_setattr(struct dentry *direntry, struct iattr *attrs)
 	struct cifsFileInfo *open_file = NULL;
 	FILE_BASIC_INFO time_buf;
 	int set_time = FALSE;
+	int set_dosattr = FALSE;
 	__u64 mode = 0xFFFFFFFFFFFFFFFFULL;
 	__u64 uid = 0xFFFFFFFFFFFFFFFFULL;
 	__u64 gid = 0xFFFFFFFFFFFFFFFFULL;
@@ -1269,15 +1270,23 @@ int cifs_setattr(struct dentry *direntry, struct iattr *attrs)
 	else if (attrs->ia_valid & ATTR_MODE) {
 		rc = 0;
 		if ((mode & S_IWUGO) == 0) /* not writeable */ {
-			if ((cifsInode->cifsAttrs & ATTR_READONLY) == 0)
+			if ((cifsInode->cifsAttrs & ATTR_READONLY) == 0) {
+				set_dosattr = TRUE;
 				time_buf.Attributes =
 					cpu_to_le32(cifsInode->cifsAttrs |
 						    ATTR_READONLY);
+			}
 		} else if ((mode & S_IWUGO) == S_IWUGO) {
-			if (cifsInode->cifsAttrs & ATTR_READONLY)
+			if (cifsInode->cifsAttrs & ATTR_READONLY) {
+				set_dosattr = TRUE;
 				time_buf.Attributes =
 					cpu_to_le32(cifsInode->cifsAttrs &
 						    (~ATTR_READONLY));
+				/* Windows ignores set to zero */
+				if(time_buf.Attributes == 0)
+					time_buf.Attributes |=
+						cpu_to_le32(ATTR_NORMAL);
+			}
 		}
 		/* BB to be implemented -
 		   via Windows security descriptors or streams */
@@ -1315,7 +1324,7 @@ int cifs_setattr(struct dentry *direntry, struct iattr *attrs)
 	} else
 		time_buf.ChangeTime = 0;
 
-	if (set_time || time_buf.Attributes) {
+	if (set_time || set_dosattr) {
 		time_buf.CreationTime = 0;	/* do not change */
 		/* In the future we should experiment - try setting timestamps
 		   via Handle (SetFileInfo) instead of by path */