Jan/WLED_MM_Infinity
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reduce risk of crashes (stack smashing) due calls to notify()

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The function uses a UDP buffer of ~1200 bytes on stack, which is only needed when actually sending out notifications.
-> separate activation checks and actual sending into two functions, to reduce stack pressure.
This commit is contained in:
Frank
2026-01-29 13:00:53 +01:00
parent c945732c8d
commit 1210881bd8
1 changed files with 25 additions and 17 deletions
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42
wled00/udp.cpp
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@@ -10,23 +10,9 @@
#define UDP_IN_MAXSIZE 1472
#define PRESUMED_NETWORK_DELAY 3 //how many ms could it take on avg to reach the receiver? This will be added to transmitted times
void notify(byte callMode, bool followUp)
{
if (!udpConnected) return;
if (!syncGroups) return;
switch (callMode)
{
case CALL_MODE_INIT: return;
case CALL_MODE_DIRECT_CHANGE: if (!notifyDirect) return; break;
case CALL_MODE_BUTTON: if (!notifyButton) return; break;
case CALL_MODE_BUTTON_PRESET: if (!notifyButton) return; break;
case CALL_MODE_NIGHTLIGHT: if (!notifyDirect) return; break;
case CALL_MODE_HUE: if (!notifyHue) return; break;
case CALL_MODE_PRESET_CYCLE: if (!notifyDirect) return; break;
case CALL_MODE_ALEXA: if (!notifyAlexa) return; break;
default: return;
}
byte udpOut[WLEDPACKETSIZE];
static void do_notify(byte callMode, bool followUp) { // WLEDMM split into two functions, to avoid stack smashing - do_notify needs 1200 bytes on stack
// DEBUG_PRINTF("[%8u %s]\tnotify(%d, %s)\tmin stack %d\n", millis(), pcTaskGetTaskName(NULL), callMode, followUp?"true ":"false", uxTaskGetStackHighWaterMark(NULL));
byte udpOut[WLEDPACKETSIZE] = {0};
Segment& mainseg = strip.getMainSegment();
udpOut[0] = 0; //0: wled notifier protocol 1: WARLS protocol
udpOut[1] = callMode;
@@ -150,6 +136,27 @@ void notify(byte callMode, bool followUp)
notificationCount = followUp ? notificationCount + 1 : 0;
}
// WLEDMM wrapper function to avoid stack smashing - do_notify needs 1200 bytes on stack, but its not actually sending anything on most notify() calls
void notify(byte callMode, bool followUp)
{
if (!udpConnected) return;
if (!syncGroups) return;
switch (callMode)
{
case CALL_MODE_INIT: return;
case CALL_MODE_DIRECT_CHANGE: if (!notifyDirect) return; break;
case CALL_MODE_BUTTON: if (!notifyButton) return; break;
case CALL_MODE_BUTTON_PRESET: if (!notifyButton) return; break;
case CALL_MODE_NIGHTLIGHT: if (!notifyDirect) return; break;
case CALL_MODE_HUE: if (!notifyHue) return; break;
case CALL_MODE_PRESET_CYCLE: if (!notifyDirect) return; break;
case CALL_MODE_ALEXA: if (!notifyAlexa) return; break;
default: return;
}
do_notify(callMode, followUp);
}
// WLEDMM cache current main segment: updated in realtimeLock, reset in exitRealtime, used in setRealTimePixel
static Segment* theMainSeg = nullptr;
static int theMainSegLength = 0;
@@ -736,6 +743,7 @@ void refreshNodeList()
void sendSysInfoUDP()
{
if (!udp2Connected) return;
// DEBUG_PRINTF("[%8u %s]\tsendSysInfoUDP()\tmin stack %d\n", millis(), pcTaskGetTaskName(NULL), uxTaskGetStackHighWaterMark(NULL));
IPAddress ip = Network.localIP();
if (!ip || ip == IPAddress(255,255,255,255)) ip = IPAddress(4,3,2,1);