Merge branch '511-be-safe-against-panics' into 'main'

sshd: Recover from per-session and per-connection panics

Closes #511

See merge request gitlab-org/gitlab-shell!464

1 files changed, 49 insertions, 0 deletions

diff --git a/internal/sshd/connection_test.go b/internal/sshd/connection_test.go
new file mode 100644
index 0000000..03e9209
--- /dev/null
+++ b/internal/sshd/connection_test.go
@@ -0,0 +1,49 @@
+package sshd
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"golang.org/x/crypto/ssh"
+)
+
+type fakeNewChannel struct {
+	channelType string
+	extraData   []byte
+}
+
+func (f *fakeNewChannel) Accept() (ssh.Channel, <-chan *ssh.Request, error) {
+	return nil, nil, nil
+}
+
+func (f *fakeNewChannel) Reject(reason ssh.RejectionReason, message string) error {
+	return nil
+}
+
+func (f *fakeNewChannel) ChannelType() string {
+	return f.channelType
+}
+
+func (f *fakeNewChannel) ExtraData() []byte {
+	return f.extraData
+}
+
+func TestPanicDuringSessionIsRecovered(t *testing.T) {
+	numSessions := 0
+	conn := newConnection(1, "127.0.0.1:50000")
+
+	newChannel := &fakeNewChannel{channelType: "session"}
+	chans := make(chan ssh.NewChannel, 1)
+	chans <- newChannel
+
+	require.NotPanics(t, func() {
+		conn.handle(context.Background(), chans, func(context.Context, ssh.Channel, <-chan *ssh.Request) {
+			numSessions += 1
+			close(chans)
+			panic("This is a panic")
+		})
+	})
+
+	require.Equal(t, numSessions, 1)
+}