fix: null-check packetPool / queueStatusPool allocCopy across 11 router/module callers

src/mesh/MeshService.cpp

@@ -110,7 +110,10 @@ int MeshService::handleFromRadio(const meshtastic_MeshPacket *mp)
     }
 
     printPacket("Forwarding to phone", mp);
-    sendToPhone(packetPool.allocCopy(*mp));
+    if (auto *c = packetPool.allocCopy(*mp))
+        sendToPhone(c);
+    else
+        LOG_DEBUG("phone-forward dropped: packetPool exhausted");
 
     return 0;
 }
@@ -205,7 +208,10 @@ void MeshService::handleToRadio(meshtastic_MeshPacket &p)
     DEBUG_HEAP_BEFORE;
     auto a = packetPool.allocCopy(p);
     DEBUG_HEAP_AFTER("MeshService::handleToRadio", a);
-    sendToMesh(a, RX_SRC_USER);
+    if (a)
+        sendToMesh(a, RX_SRC_USER);
+    else
+        LOG_WARN("handleToRadio: packetPool exhausted, dropping ToRadio packet");
 
     bool loopback = false; // if true send any packet the phone sends back itself (for testing)
     if (loopback) {
@@ -225,6 +231,10 @@ bool MeshService::cancelSending(PacketId id)
 ErrorCode MeshService::sendQueueStatusToPhone(const meshtastic_QueueStatus &qs, ErrorCode res, uint32_t mesh_packet_id)
 {
     meshtastic_QueueStatus *copied = queueStatusPool.allocCopy(qs);
+    if (!copied) {
+        LOG_DEBUG("sendQueueStatusToPhone: queueStatusPool exhausted, skipping");
+        return ERRNO_UNKNOWN;
+    }
 
     copied->res = res;
     copied->mesh_packet_id = mesh_packet_id;
@@ -265,7 +275,12 @@ void MeshService::sendToMesh(meshtastic_MeshPacket *p, RxSource src, bool ccToPh
         auto a = packetPool.allocCopy(*p);
         DEBUG_HEAP_AFTER("MeshService::sendToMesh", a);
 
-        sendToPhone(a);
+        if (a)
+            sendToPhone(a);
+        // else: packetPool exhausted; the cc-to-phone copy is dropped here.
+        // The original packet is still queued to the mesh; phone visibility
+        // of cc'd local sends depends on whether the RX path forwards it,
+        // which is not guaranteed for non-broadcast / non-local-dest sends.
     }
 
     // Router may ask us to release the packet if it wasn't sent

src/mesh/NextHopRouter.cpp

@@ -31,8 +31,11 @@ ErrorCode NextHopRouter::send(meshtastic_MeshPacket *p)
 
     // If it's from us, ReliableRouter already handles retransmissions if want_ack is set. If a next hop is set and hop limit is
     // not 0 or want_ack is set, start retransmissions
-    if ((!isFromUs(p) || !p->want_ack) && p->next_hop != NO_NEXT_HOP_PREFERENCE && (p->hop_limit > 0 || p->want_ack))
-        startRetransmission(packetPool.allocCopy(*p)); // start retransmission for relayed packet
+    if ((!isFromUs(p) || !p->want_ack) && p->next_hop != NO_NEXT_HOP_PREFERENCE && (p->hop_limit > 0 || p->want_ack)) {
+        if (auto *retxCopy = packetPool.allocCopy(*p))
+            startRetransmission(retxCopy); // start retransmission for relayed packet
+        // else: pool exhausted; relayed packet is still sent below — just no retransmission
+    }
 
     return Router::send(p);
 }
@@ -146,6 +149,10 @@ bool NextHopRouter::perhapsRebroadcast(const meshtastic_MeshPacket *p)
             if (isRebroadcaster()) {
                 if (p->next_hop == NO_NEXT_HOP_PREFERENCE || p->next_hop == nodeDB->getLastByteOfNodeNum(getNodeNum())) {
                     meshtastic_MeshPacket *tosend = packetPool.allocCopy(*p); // keep a copy because we will be sending it
+                    if (!tosend) {
+                        LOG_WARN("Rebroadcast skipped: packetPool exhausted (from=%x)", p->relay_node);
+                        return false;
+                    }
                     LOG_INFO("Rebroadcast received message coming from %x", p->relay_node);
 
                     // If exhausting hops, force hop_limit = 0 regardless of other logic
@@ -319,14 +326,14 @@ int32_t NextHopRouter::doRetransmissions()
                             LOG_INFO("Resetting next hop for packet with dest 0x%x\n", p.packet->to);
                             sentTo->next_hop = NO_NEXT_HOP_PREFERENCE;
                         }
-                        FloodingRouter::send(packetPool.allocCopy(*p.packet));
+                        if (auto *c = packetPool.allocCopy(*p.packet)) FloodingRouter::send(c);
                     } else {
-                        NextHopRouter::send(packetPool.allocCopy(*p.packet));
+                        if (auto *c = packetPool.allocCopy(*p.packet)) NextHopRouter::send(c);
                     }
                 } else {
                     // Note: we call the superclass version because we don't want to have our version of send() add a new
                     // retransmission record
-                    FloodingRouter::send(packetPool.allocCopy(*p.packet));
+                    if (auto *c = packetPool.allocCopy(*p.packet)) FloodingRouter::send(c);
                 }
 
                 // Queue again

src/mesh/ReliableRouter.cpp

@@ -21,7 +21,9 @@ ErrorCode ReliableRouter::send(meshtastic_MeshPacket *p)
         auto copy = packetPool.allocCopy(*p);
         DEBUG_HEAP_AFTER("ReliableRouter::send", copy);
 
-        startRetransmission(copy, NUM_RELIABLE_RETX);
+        if (copy)
+            startRetransmission(copy, NUM_RELIABLE_RETX);
+        // else: pool exhausted; the packet itself is still sent — just no retry
     }
 
     /* If we have pending retransmissions, add the airtime of this packet to it, because during that time we cannot receive an

src/mesh/Router.cpp

@@ -384,12 +384,15 @@ ErrorCode Router::send(meshtastic_MeshPacket *p)
             return encodeResult; // FIXME - this isn't a valid ErrorCode
         }
 #if !MESHTASTIC_EXCLUDE_MQTT
-        // Only publish to MQTT if we're the original transmitter of the packet
-        if (moduleConfig.mqtt.enabled && isFromUs(p) && mqtt) {
+        // Only publish to MQTT if we're the original transmitter of the packet.
+        // Skip on packetPool exhaustion (p_decoded == nullptr) — onSend would
+        // dereference the reference and crash; better to drop the MQTT publish
+        // for this one packet than panic the radio.
+        if (p_decoded && moduleConfig.mqtt.enabled && isFromUs(p) && mqtt) {
             mqtt->onSend(*p, *p_decoded, chIndex);
         }
 #endif
-        packetPool.release(p_decoded);
+        packetPool.release(p_decoded); // release() handles nullptr
     }
 
 #if HAS_UDP_MULTICAST

src/modules/AtakPluginModule.cpp

@@ -197,8 +197,12 @@ void AtakPluginModule::alterReceivedProtobuf(meshtastic_MeshPacket &mp, meshtast
             }
         }
         auto decompressedCopy = packetPool.allocCopy(mp);
+        if (!decompressedCopy) {
+            LOG_DEBUG("AtakPluginModule: packetPool exhausted, skipping decompressed phone forward");
+            return;
+        }
         decompressedCopy->decoded.payload.size =
-            pb_encode_to_bytes(decompressedCopy->decoded.payload.bytes, sizeof(decompressedCopy->decoded.payload),
+            pb_encode_to_bytes(decompressedCopy->decoded.payload.bytes, sizeof(decompressedCopy->decoded.payload.bytes),
                                meshtastic_TAKPacket_fields, &uncompressed);
 
         service->sendToPhone(decompressedCopy);

src/modules/NodeInfoModule.cpp

@@ -61,12 +61,15 @@ bool NodeInfoModule::handleReceivedProtobuf(const meshtastic_MeshPacket &mp, mes
     // if user has changed while packet was not for us, inform phone
     if (hasChanged && !wasBroadcast && !isToUs(&mp)) {
         auto packetCopy = packetPool.allocCopy(mp); // Keep a copy of the packet for later analysis
+        if (packetCopy) {
+            // Re-encode the user protobuf, as we have stripped out the user.id
+            packetCopy->decoded.payload.size = pb_encode_to_bytes(
+                packetCopy->decoded.payload.bytes, sizeof(packetCopy->decoded.payload.bytes), &meshtastic_User_msg, &p);
 
-        // Re-encode the user protobuf, as we have stripped out the user.id
-        packetCopy->decoded.payload.size = pb_encode_to_bytes(
-            packetCopy->decoded.payload.bytes, sizeof(packetCopy->decoded.payload.bytes), &meshtastic_User_msg, &p);
-
-        service->sendToPhone(packetCopy);
+            service->sendToPhone(packetCopy);
+        } else {
+            LOG_DEBUG("NodeInfoModule: packetPool exhausted, skipping phone forward");
+        }
     }
 
     pruneLastNodeInfoCache();