Add out of bound check for Leader Key sequence array (#5840)

[qmk_firmware.git] / quantum / process_keycode / process_leader.c

diff --git a/quantum/process_keycode/process_leader.c b/quantum/process_keycode/process_leader.c
index b32fc1db6a04b89cbc03d4fcbe7a7e79ad5bd83b..ee8099ca216024191b7c929b25da5336c614ec1d 100644 (file)
--- a/quantum/process_keycode/process_leader.c
+++ b/quantum/process_keycode/process_leader.c
@@ -17,6 +17,9 @@
 #ifdef LEADER_ENABLE
 
 #include "process_leader.h"
+#ifdef __arm__
+#   include <string.h>
+#endif
 
 #ifndef LEADER_TIMEOUT
   #define LEADER_TIMEOUT 300
@@ -35,31 +38,41 @@ uint16_t leader_time = 0;
 uint16_t leader_sequence[5] = {0, 0, 0, 0, 0};
 uint8_t leader_sequence_size = 0;
 
+void qk_leader_start(void) {
+  if (leading) { return; }
+  leader_start();
+  leading = true;
+  leader_time = timer_read();
+  leader_sequence_size = 0;
+  memset(leader_sequence, 0, sizeof(leader_sequence));
+}
+
 bool process_leader(uint16_t keycode, keyrecord_t *record) {
   // Leader key set-up
   if (record->event.pressed) {
+    if (leading) {
+      if (timer_elapsed(leader_time) < LEADER_TIMEOUT) {
+#ifndef LEADER_KEY_STRICT_KEY_PROCESSING
+        if ((keycode >= QK_MOD_TAP && keycode <= QK_MOD_TAP_MAX) || (keycode >= QK_LAYER_TAP && keycode <= QK_LAYER_TAP_MAX)) {
+          keycode = keycode & 0xFF;
+        }
+#endif // LEADER_KEY_STRICT_KEY_PROCESSING
+        if ( leader_sequence_size < ( sizeof(leader_sequence) / sizeof(leader_sequence[0]) ) ) {
+          leader_sequence[leader_sequence_size] = keycode;
+          leader_sequence_size++;
+        } else {
+          leading = false;
+          leader_end();
+        }
 #ifdef LEADER_PER_KEY_TIMING
-    leader_time = timer_read();
+        leader_time = timer_read();
 #endif
-    if (!leading && keycode == KC_LEAD) {
-      leader_start();
-      leading = true;
-#ifndef LEADER_PER_KEY_TIMING
-      leader_time = timer_read();
-#endif
-      leader_time = timer_read();
-      leader_sequence_size = 0;
-      leader_sequence[0] = 0;
-      leader_sequence[1] = 0;
-      leader_sequence[2] = 0;
-      leader_sequence[3] = 0;
-      leader_sequence[4] = 0;
-      return false;
-    }
-    if (leading && timer_elapsed(leader_time) < LEADER_TIMEOUT) {
-      leader_sequence[leader_sequence_size] = keycode;
-      leader_sequence_size++;
-      return false;
+        return false;
+      }
+    } else {
+      if (keycode == KC_LEAD) {
+        qk_leader_start();
+      }
     }
   }
   return true;