Assign controlling terminal when tty is opened and support NOCTTY

PiperOrigin-RevId: 357015186

3 files changed, 7 insertions, 6 deletions

diff --git a/pkg/sentry/fs/tty/master.go b/pkg/sentry/fs/tty/master.go
index b91184b1b..1cf869b62 100644
--- a/pkg/sentry/fs/tty/master.go
+++ b/pkg/sentry/fs/tty/master.go
@@ -153,7 +153,7 @@ func (mf *masterFileOperations) Write(ctx context.Context, _ *fs.File, src userm
 }
 
 // Ioctl implements fs.FileOperations.Ioctl.
-func (mf *masterFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+func (mf *masterFileOperations) Ioctl(ctx context.Context, file *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
 	t := kernel.TaskFromContext(ctx)
 	if t == nil {
 		// ioctl(2) may only be called from a task goroutine.
@@ -189,7 +189,7 @@ func (mf *masterFileOperations) Ioctl(ctx context.Context, _ *fs.File, io userme
 	case linux.TIOCSCTTY:
 		// Make the given terminal the controlling terminal of the
 		// calling process.
-		return 0, mf.t.setControllingTTY(ctx, args, true /* isMaster */)
+		return 0, mf.t.setControllingTTY(ctx, args, true /* isMaster */, file.Flags().Read)
 	case linux.TIOCNOTTY:
 		// Release this process's controlling terminal.
 		return 0, mf.t.releaseControllingTTY(ctx, args, true /* isMaster */)
diff --git a/pkg/sentry/fs/tty/replica.go b/pkg/sentry/fs/tty/replica.go
index 385d230fb..0e3eea3bd 100644
--- a/pkg/sentry/fs/tty/replica.go
+++ b/pkg/sentry/fs/tty/replica.go
@@ -138,7 +138,7 @@ func (sf *replicaFileOperations) Write(ctx context.Context, _ *fs.File, src user
 }
 
 // Ioctl implements fs.FileOperations.Ioctl.
-func (sf *replicaFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+func (sf *replicaFileOperations) Ioctl(ctx context.Context, file *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
 	t := kernel.TaskFromContext(ctx)
 	if t == nil {
 		// ioctl(2) may only be called from a task goroutine.
@@ -167,7 +167,7 @@ func (sf *replicaFileOperations) Ioctl(ctx context.Context, _ *fs.File, io userm
 	case linux.TIOCSCTTY:
 		// Make the given terminal the controlling terminal of the
 		// calling process.
-		return 0, sf.si.t.setControllingTTY(ctx, args, false /* isMaster */)
+		return 0, sf.si.t.setControllingTTY(ctx, args, false /* isMaster */, file.Flags().Read)
 	case linux.TIOCNOTTY:
 		// Release this process's controlling terminal.
 		return 0, sf.si.t.releaseControllingTTY(ctx, args, false /* isMaster */)
diff --git a/pkg/sentry/fs/tty/terminal.go b/pkg/sentry/fs/tty/terminal.go
index 4f431d74d..d551267af 100644
--- a/pkg/sentry/fs/tty/terminal.go
+++ b/pkg/sentry/fs/tty/terminal.go
@@ -64,13 +64,14 @@ func newTerminal(ctx context.Context, d *dirInodeOperations, n uint32) *Terminal
 
 // setControllingTTY makes tm the controlling terminal of the calling thread
 // group.
-func (tm *Terminal) setControllingTTY(ctx context.Context, args arch.SyscallArguments, isMaster bool) error {
+func (tm *Terminal) setControllingTTY(ctx context.Context, args arch.SyscallArguments, isMaster bool, readable bool) error {
 	task := kernel.TaskFromContext(ctx)
 	if task == nil {
 		panic("setControllingTTY must be called from a task context")
 	}
 
-	return task.ThreadGroup().SetControllingTTY(tm.tty(isMaster), args[2].Int())
+	steal := args[2].Int() == 1
+	return task.ThreadGroup().SetControllingTTY(tm.tty(isMaster), steal, readable)
 }
 
 // releaseControllingTTY removes tm as the controlling terminal of the calling