From 1dc92a8c71c32fc82a6938a25c7e9dbca435abb0 Mon Sep 17 00:00:00 2001
From: Wim <wim@42.be>
Date: Wed, 22 Feb 2023 22:32:34 +0100
Subject: [PATCH] Add reference to terminal in lineDiscipline

---
 pkg/sentry/fsimpl/devpts/line_discipline.go | 15 +++++++--------
 pkg/sentry/fsimpl/devpts/terminal.go        |  9 +++++++--
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/pkg/sentry/fsimpl/devpts/line_discipline.go b/pkg/sentry/fsimpl/devpts/line_discipline.go
index 3fd90db84..3ca11a985 100644
--- a/pkg/sentry/fsimpl/devpts/line_discipline.go
+++ b/pkg/sentry/fsimpl/devpts/line_discipline.go
@@ -112,9 +112,8 @@ type lineDiscipline struct {
 	// replicaWaiter is used to wait on the replica end of the TTY.
 	replicaWaiter waiter.Queue
 
-	// fgProcessGroup is the foreground process group that is currently
-	// connected to this TTY.
-	fgProcessGroup *kernel.ProcessGroup
+	// terminal is the terminal linked to this lineDiscipline
+	terminal *Terminal
 }
 
 func newLineDiscipline(termios linux.KernelTermios) *lineDiscipline {
@@ -124,8 +123,8 @@ func newLineDiscipline(termios linux.KernelTermios) *lineDiscipline {
 	return &ld
 }
 
-func (l *lineDiscipline) SetForegroundProcessGroup(pg *kernel.ProcessGroup) {
-	l.fgProcessGroup = pg
+func (l *lineDiscipline) SetTerminal(tm *Terminal) {
+	l.terminal = tm
 }
 
 // getTermios gets the linux.Termios for the tty.
@@ -402,11 +401,11 @@ func (*inputQueueTransformer) transform(l *lineDiscipline, q *queue, buf []byte)
 				cBytes[0] = '\r'
 			}
 		case l.termios.ControlCharacters[linux.VINTR]: // ctrl-c
-			l.fgProcessGroup.SendSignal(kernel.SignalInfoPriv(linux.SIGINT))
+			l.terminal.fgProcessGroup.SendSignal(kernel.SignalInfoPriv(linux.SIGINT))
 		case l.termios.ControlCharacters[linux.VSUSP]: // ctrl-z
-			l.fgProcessGroup.SendSignal(kernel.SignalInfoPriv(linux.SIGTSTP))
+			l.terminal.fgProcessGroup.SendSignal(kernel.SignalInfoPriv(linux.SIGTSTP))
 		case l.termios.ControlCharacters[linux.VQUIT]: // ctrl-\
-			l.fgProcessGroup.SendSignal(kernel.SignalInfoPriv(linux.SIGQUIT))
+			l.terminal.fgProcessGroup.SendSignal(kernel.SignalInfoPriv(linux.SIGQUIT))
 		}
 
 		// In canonical mode, we discard non-terminating characters
diff --git a/pkg/sentry/fsimpl/devpts/terminal.go b/pkg/sentry/fsimpl/devpts/terminal.go
index 6c153f9c8..ed03ffda0 100644
--- a/pkg/sentry/fsimpl/devpts/terminal.go
+++ b/pkg/sentry/fsimpl/devpts/terminal.go
@@ -39,6 +39,10 @@ type Terminal struct {
 	// replicaKTTY contains the controlling process of the replica end of this
 	// terminal. This field is immutable.
 	replicaKTTY *kernel.TTY
+
+	// fgProcessGroup is the foreground process group that is currently
+	// connected to this TTY.
+	fgProcessGroup *kernel.ProcessGroup
 }
 
 func newTerminal(n uint32) *Terminal {
@@ -49,6 +53,8 @@ func newTerminal(n uint32) *Terminal {
 		masterKTTY:  &kernel.TTY{Index: n},
 		replicaKTTY: &kernel.TTY{Index: n},
 	}
+
+	t.ld.SetTerminal(&t)
 	return &t
 }
 
@@ -105,8 +111,7 @@ func (tm *Terminal) setForegroundProcessGroup(ctx context.Context, args arch.Sys
 		return 0, err
 	}
 
-	// Put the processgroup also in line discipline for further signal handling
-	tm.ld.SetForegroundProcessGroup(task.ThreadGroup().ProcessGroup())
+	tm.fgProcessGroup = task.ThreadGroup().ProcessGroup()
 
 	ret, err := task.ThreadGroup().SetForegroundProcessGroup(tm.tty(isMaster), kernel.ProcessGroupID(pgid))
 	return uintptr(ret), err