* cygheap.cc (cygheap_init): Accomodate set_process_privilege change.

* cygheap.h (cygheap_user::curr_primary_token): New member.
	(cygheap_user::primary_token): New method.
	(cygheap_user::deimpersonate): Always revert to processes'
	impersonation token.
	(cygheap_user::reimpersonate): Set processes' or setuid token as
	necessary.
	(cygheap_user::has_impersonation_tokens): Look for curr_primary_token
	value.
	(cygheap_user::close_impersonation_tokens): Close curr_primary_token
	here if necessary.  Don't reset token values to NO_IMPERSONATION since
	that's done in uinfo_init anyway.
	(init_cygheap::luid): New LUID array keeping privilege LUIDs.
	* cygtls.cc (_cygtls::init_thread): Call cygheap->user.reimpersonate.
	* dcrt0.cc (hProcToken): New global variable to keep process token.
	(hProcImpToken): Ditto for process impersonation token.
	(dll_crt0_0): Open process token here once.  Duplicate to create
	hProcImpToken.
	(dll_crt0_1): Call set_cygwin_privileges.
	* environ.cc (allow_ntea): Drop duplicate declaration.
	(allow_smbntsec): Ditto.
	(set_traverse): Only set allow_traverse here.
	(environ_init): Ditto.
	* fhandler_disk_file.cc (fhandler_disk_file::fchmod): Drop call to
	enable_restore_privilege.
	(fhandler_disk_file::fchown): Ditto.
	(fhandler_disk_file::facl): Ditto.
	* fork.cc (fork_child): Move call to cygheap->user.reimpersonate after
	syn with parent. Call set_cygwin_privileges.
	* grp.cc (internal_getgroups): Use hProcImpToken instead of opening
	process token.
	* path.cc (fs_info::update): Bypass traverse checking when retrieving
	volume information using push/pop_thread_privileges.
	* registry.cc (load_registry_hive): Drop setting restore privilege
	since it's already set if available.
	* sec_helper.cc: Include cygtls.h.
	(cygpriv): Privilege string array.
	(privilege_luid): New function, evaluate LUID from cygpriv_idx.
	(privilege_luid_by_name): New function, evaluate LUID from privilege
	string.
	(privilege_name): New function, evaluate privilege string from
	cygpriv_idx.
	(set_privilege): New static function called by set_process_privilege
	and set_thread_privilege.  Call privilege_luid to get privilege LUID.
	Fix bug in return value evaluation. Improve debug output.
	(set_cygwin_privileges): New function.
	(set_process_privilege): Remove.
	(enable_restore_privilege): Remove.
	* security.cc (allow_traverse): New global variable.
	(sys_privs): Change type to cygpriv_idx and store privilege indices
	instead of strings.
	(SYSTEM_PRIVILEGES_COUNT): Renamed from SYSTEM_PERMISSION_COUNT.
	(get_system_priv_list): Don't use numerical constant in malloc call.
	Use privilege_luid to get privilege LUIDs.
	(get_priv_list): Call privilege_luid_by_name to get LUIDs. Improve
	inner privilege LUID comparison loop.
	(create_token): Enable create token privilege using
	push/pop_self_privileges. Use hProcToken instead of opening process
	token. Use default DACL when duplicating token.
	(subauth): Enable tcb privilege using push/pop_self_privileges.
	Use sec_none instead of homw made security attributes when duplicating
	token.
	(check_file_access): Don't duplicate access token, use active
	impersonation token as is.
	* security.h (enum cygpriv_idx): New enumeration type enumerating
	possible privileges.
	(privilege_luid): Declare new function.
	(privilege_luid_by_name): Ditto.
	(privilege_name): Ditto.
	(allow_traverse): Declare.
	(set_privilege): Declare function.
	(set_process_privilege): Define as macro.
	(enable_restore_privilege): Remove declaration.
	(_push_thread_privilege): Define macro.
	(push_thread_privilege): Ditto.
	(pop_thread_privilege): Ditto.
	(pop_self_privilege): Ditto.
	* spawn.cc (spawn_guts): Use cygheap->user.primary_token instead of
	cygheap->user.token.
	* syscalls.cc (statvfs): Bypass traverse checking when retrieving
	volume information using push/pop_thread_privileges. Rearrange code
	to simplify push/pop bracketing.
	(seteuid32): Use hProcToken instead of opening process token. Call
	cygheap->user.deimpersonate instead of RevertToSelf.  Create
	impersonation token from primary internal or external token.  Set
	cygheap->user.curr_primary_token and cygheap->user.current_token
	privileges once here.  Drop "failed" and "failed_ptok" labels.
	Drop setting DefaultDacl of process token.
	(setegid32): Use hProcToken and hProcImpToken instead of opening
	process token. Always reimpersonate afterwards.
	* uinfo.cc (cygheap_user::init): Use hProcToken instead of opening
	process token.
	(internal_getlogin): Ditto. Set hProcImpToken, too.
	(uinfo_init): Initialize cygheap->user.curr_primary_token.
	* winsup.h (hProcToken): Declare.
	(hProcImpToken): Declare.

winsup/cygwin/path.cc

@@ -348,6 +348,7 @@ fs_info::update (const char *win32_path)
 {
   char fsname [CYG_MAX_PATH];
   char root_dir [CYG_MAX_PATH];
+  bool ret;
 
   if (!rootdir (win32_path, root_dir))
     {
@@ -372,6 +373,10 @@ fs_info::update (const char *win32_path)
     }
   name_hash = tmp_name_hash;
 
+  /* I have no idea why, but some machines require SeChangeNotifyPrivilege
+     to access volume information. */
+  push_thread_privilege (SE_CHANGE_NOTIFY_PRIV, true);
+
   drive_type (GetDriveType (root_dir));
   if (drive_type () == DRIVE_REMOTE
       || (drive_type () == DRIVE_UNKNOWN
@@ -380,9 +385,12 @@ fs_info::update (const char *win32_path)
   else
     is_remote_drive (false);
 
-  if (!GetVolumeInformation (root_dir, NULL, 0, &status.serial, NULL,
-			     &status.flags, fsname, sizeof (fsname))
-      && !is_remote_drive ())
+  ret = GetVolumeInformation (root_dir, NULL, 0, &status.serial, NULL,
+			      &status.flags, fsname, sizeof (fsname));
+
+  pop_thread_privilege ();
+
+  if (!ret && !is_remote_drive ())
     {
       debug_printf ("Cannot get volume information (%s), %E", root_dir);
       has_buggy_open (false);
@@ -390,6 +398,7 @@ fs_info::update (const char *win32_path)
       flags () = serial () = 0;
       return false;
     }
+
   /* FIXME: Samba by default returns "NTFS" in file system name, but
    * doesn't support Extended Attributes. If there's some fast way to
    * distinguish between samba and real ntfs, it should be implemented