(diskfs_S_file_chown): Perform the permission check for each ID in the

chain.

1 files changed, 16 insertions, 7 deletions

diff --git a/libdiskfs/file-chown.c b/libdiskfs/file-chown.c
index c0f685c7..58ea51cf 100644
--- a/libdiskfs/file-chown.c
+++ b/libdiskfs/file-chown.c
@@ -1,5 +1,5 @@
 /* libdiskfs implementetation of fs.defs: file_chown
-   Copyright (C) 1992, 1993, 1994 Free Software Foundation
+   Copyright (C) 1992, 1993, 1994, 1995 Free Software Foundation
 
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
@@ -24,15 +24,24 @@ diskfs_S_file_chown (struct protid *cred,
 		     uid_t uid,
 		     gid_t gid)
 {
+  struct userid *id;
+
   CHANGE_NODE_FIELD (cred,
 		   ({
 		     err = diskfs_isowner (np, cred);
-		     if (err
-			 || ((!diskfs_isuid (uid, cred)
-			      || !diskfs_groupmember (gid, cred))
-			     && !diskfs_isuid (0, cred)))
-		       err = EPERM;
-		     else
+		     if (!err)
+		       {
+			 assert (cred->id);
+			 for (id = cred->id; id && !err; id = id->next)
+			   {
+			     if (diskfs_idhasuid (0, id))
+			       continue;
+			     if (!diskfs_idhasuid (uid, cred)
+				 || !diskfs_idhasgid (gid, cred))
+			       err = EPERM;
+			   }
+		       }
+		     if (!err)
 		       {
 			 np->dn_stat.st_uid = uid;
 			 np->dn_stat.st_gid = gid;