diff --git a/src/libeis-device.c b/src/libeis-device.c
index a7bf00d..df2d009 100644
--- a/src/libeis-device.c
+++ b/src/libeis-device.c
@@ -428,6 +428,13 @@ client_msg_button(struct eis_button *button, uint32_t btn, uint32_t state)
 				       "Button event for non-button device");
 	}
 
+	if (btn >= KEY_CNT)
+		return brei_result_new(EIS_CONNECTION_DISCONNECT_REASON_PROTOCOL,
+				       "Button event for invalid button %x (KEY_CNT is %#x)", btn, KEY_CNT);
+
+	if (!eis_device_update_key_button_state(device, btn, state))
+		return NULL;
+
 	if (device->state == EIS_DEVICE_STATE_EMULATING) {
 		eis_queue_pointer_button_event(device, btn, !!state);
 		return NULL;
@@ -598,6 +605,13 @@ client_msg_keyboard_key(struct eis_keyboard *keyboard, uint32_t key, uint32_t st
 				       "Key event for non-keyboard device");
 	}
 
+	if (key >= KEY_CNT)
+		return brei_result_new(EIS_CONNECTION_DISCONNECT_REASON_PROTOCOL,
+				       "Key event for invalid key %x (KEY_CNT is %#x)", key, KEY_CNT);
+
+	if (!eis_device_update_key_button_state(device, key, state))
+		return NULL;
+
 	if (device->state == EIS_DEVICE_STATE_EMULATING) {
 		eis_queue_keyboard_key_event(device, key, !!state);
 		return NULL;
@@ -1447,6 +1461,8 @@ eis_device_pause(struct eis_device *device)
 
 	device->state = EIS_DEVICE_STATE_PAUSED;
 	eis_device_event_paused(device, eis_client_get_next_serial(client));
+
+	memset(device->key_button_state.down, 0, sizeof(device->key_button_state.down));
 }
 
 _public_ void
diff --git a/src/libeis-device.h b/src/libeis-device.h
index 5f6f2a1..97e74fa 100644
--- a/src/libeis-device.h
+++ b/src/libeis-device.h
@@ -26,10 +26,14 @@
 
 #include "libeis.h"
 
+#include "util-bits.h"
 #include "util-object.h"
 #include "util-list.h"
 #include "brei-shared.h"
 
+#define KEY_MAX 0x2ffU
+#define KEY_CNT (KEY_MAX + 1)
+
 enum eis_device_state {
 	EIS_DEVICE_STATE_NEW,
 	EIS_DEVICE_STATE_AWAITING_READY,
@@ -75,6 +79,9 @@ struct eis_device {
 		bool x_is_cancelled, y_is_cancelled;
 	} scroll_state;
 
+	struct {
+		unsigned char down[NCHARS(KEY_CNT)];
+	} key_button_state;
 };
 
 struct eis_touch {
@@ -118,6 +125,21 @@ OBJECT_DECLARE_GETTER(eis_device, button_interface, const struct eis_button_inte
 OBJECT_DECLARE_GETTER(eis_device, keyboard_interface, const struct eis_keyboard_interface *);
 OBJECT_DECLARE_GETTER(eis_device, touchscreen_interface, const struct eis_touchscreen_interface *);
 
+static inline bool
+eis_device_update_key_button_state(struct eis_device *device, uint32_t key_btn, uint32_t state)
+{
+	if (state) {
+		if (bit_is_set(device->key_button_state.down, key_btn))
+			return false;
+		set_bit(device->key_button_state.down, key_btn);
+	} else {
+		if (!bit_is_set(device->key_button_state.down, key_btn))
+			return false;
+		clear_bit(device->key_button_state.down, key_btn);
+	}
+	return true;
+}
+
 void
 eis_device_set_client_keymap(struct eis_device *device,
 		      enum eis_keymap_type type,
diff --git a/test/test-ei-device.c b/test/test-ei-device.c
index 261de35..df24604 100644
--- a/test/test-ei-device.c
+++ b/test/test-ei-device.c
@@ -390,10 +390,20 @@ MUNIT_TEST(test_ei_device_button_button)
 		struct ei_device *device = peck_ei_get_default_pointer(peck);
 		ei_device_button_button(device, BTN_LEFT, true);
 		ei_device_frame(device, peck_ei_now(peck));
+
+		/* double press is quietly ignored */
+		ei_device_button_button(device, BTN_LEFT, true);
+		ei_device_frame(device, peck_ei_now(peck));
+
 		ei_device_button_button(device, BTN_RIGHT, true);
 		ei_device_frame(device, peck_ei_now(peck));
 		ei_device_button_button(device, BTN_RIGHT, false);
 		ei_device_frame(device, peck_ei_now(peck));
+
+		/* double release is quietly ignored */
+		ei_device_button_button(device, BTN_RIGHT, false);
+		ei_device_frame(device, peck_ei_now(peck));
+
 		ei_device_button_button(device, BTN_LEFT, false);
 		ei_device_frame(device, peck_ei_now(peck));
 	}
@@ -421,6 +431,7 @@ MUNIT_TEST(test_ei_device_button_button)
 		munit_assert_int(eis_event_button_get_button(lu), ==, BTN_LEFT);
 		munit_assert_false(eis_event_button_get_is_press(lu));
 
+		peck_assert_no_eis_events(eis);
 	}
 
 	return MUNIT_OK;
@@ -439,6 +450,15 @@ MUNIT_TEST(test_ei_device_keyboard_key)
 		struct ei_device *device = peck_ei_get_default_keyboard(peck);
 		ei_device_keyboard_key(device, KEY_Q, true);
 		ei_device_frame(device, peck_ei_now(peck));
+
+		/* Double press is quietly ignored */
+		ei_device_keyboard_key(device, KEY_Q, true);
+		ei_device_frame(device, peck_ei_now(peck));
+
+		ei_device_keyboard_key(device, KEY_Q, false);
+		ei_device_frame(device, peck_ei_now(peck));
+
+		/* Double release is quietly ignored */
 		ei_device_keyboard_key(device, KEY_Q, false);
 		ei_device_frame(device, peck_ei_now(peck));
 	}