- PTY code which support pseudo console has a problem that causes
handle leaks. Four of these are bug in pty code, and the other
one seems to be a bug of Windows10. ClosePseudoConsole() fails
to close one internal handle. This patch fixes the issue.
---
winsup/cygwin/fhandler_tty.cc | 16 ++++++++++++++--
winsup/cygwin/ntdll.h | 13 +++++++++++++
2 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/winsup/cygwin/fhandler_tty.cc b/winsup/cygwin/fhandler_tty.cc
index ca4dc1c20..1a3bdc5ea 100644
--- a/winsup/cygwin/fhandler_tty.cc
+++ b/winsup/cygwin/fhandler_tty.cc
@@ -2224,11 +2224,21 @@ fhandler_pty_master::close ()
/* Terminate helper process */
SetEvent (get_ttyp ()->h_helper_goodbye);
WaitForSingleObject (get_ttyp ()->h_helper_process, INFINITE);
+ CloseHandle (get_ttyp ()->h_helper_goodbye);
+ CloseHandle (get_ttyp ()->h_helper_process);
/* FIXME: Pseudo console can be accessed via its handle
only in the process which created it. What else can we do? */
if (master_pid_tmp == myself->pid)
- /* Release pseudo console */
- ClosePseudoConsole (get_pseudo_console ());
+ {
+ /* ClosePseudoConsole() seems to have a bug that one
+ internal handle remains opened. This causes handle leak.
+ This is a workaround for this problem. */
+ HPCON_INTERNAL *hp = (HPCON_INTERNAL *) get_pseudo_console ();
+ HANDLE tmp = hp->hConHostProcess;
+ /* Release pseudo console */
+ ClosePseudoConsole (get_pseudo_console ());
+ CloseHandle (tmp);
+ }
get_ttyp ()->switch_to_pcon_in = false;
get_ttyp ()->switch_to_pcon_out = false;
}
@@ -3191,6 +3201,8 @@ fhandler_pty_master::setup_pseudoconsole ()
TRUE, EXTENDED_STARTUPINFO_PRESENT,
NULL, NULL, &si_helper.StartupInfo, &pi_helper);
WaitForSingleObject (hello, INFINITE);
+ CloseHandle (hello);
+ CloseHandle (pi_helper.hThread);
/* Retrieve pseudo console handles */
DWORD rLen;
char buf[64];
diff --git a/winsup/cygwin/ntdll.h b/winsup/cygwin/ntdll.h
index 1c07d0255..8a08111db 100644
--- a/winsup/cygwin/ntdll.h
+++ b/winsup/cygwin/ntdll.h
@@ -1763,4 +1763,17 @@ extern "C"
return status;
}
}
+
+/* This is for pseudo console workaround. ClosePseudoConsole()
+ seems to have a bug that one internal handle remains opend.
+ This causes handle leak. To close this handle, it is needed
+ to access internal of HPCON. HPCON_INTERNAL is defined for
+ this purpose. The structure of internal of HPCON is not
+ documented. Refer to: https://github.com/Biswa96/XConPty */
+typedef struct _HPCON_INTERNAL
+{
+ HANDLE hWritePipe;
+ HANDLE hConDrvReference;
+ HANDLE hConHostProcess;
+} HPCON_INTERNAL;
#endif
--
2.21.0
