Enable -Wconversion for nrfconnect platform bits. (#25383)

Author: bzbarsky-apple

src/platform/OpenThread/GenericThreadStackManagerImpl_OpenThread.cpp

@@ -482,7 +482,8 @@ void GenericThreadStackManagerImpl_OpenThread<ImplClass>::_OnNetworkScanFinished
         scanResponse.lqi             = aResult->mLqi;
         scanResponse.extendedAddress = Encoding::BigEndian::Get64(aResult->mExtAddress.m8);
         scanResponse.extendedPanId   = Encoding::BigEndian::Get64(aResult->mExtendedPanId.m8);
-        scanResponse.networkNameLen  = strnlen(aResult->mNetworkName.m8, OT_NETWORK_NAME_MAX_SIZE);
+        static_assert(OT_NETWORK_NAME_MAX_SIZE <= UINT8_MAX, "Network name length won't fit");
+        scanResponse.networkNameLen = static_cast<uint8_t>(strnlen(aResult->mNetworkName.m8, OT_NETWORK_NAME_MAX_SIZE));
         memcpy(scanResponse.networkName, aResult->mNetworkName.m8, scanResponse.networkNameLen);
 
         mScanResponseIter.Add(&scanResponse);
@@ -1168,7 +1169,7 @@ CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_WriteThreadNetw
                 }
                 else
                 {
-                    lastRssi.SetNonNull(((neighInfo.mLastRssi > 0) ? 0 : neighInfo.mLastRssi));
+                    lastRssi.SetNonNull(min(static_cast<int8_t>(0), neighInfo.mLastRssi));
                 }
 
                 neighborTable.averageRssi      = averageRssi;

src/platform/Zephyr/BUILD.gn

@@ -76,4 +76,6 @@ static_library("Zephyr") {
   if (chip_malloc_sys_heap) {
     sources += [ "SysHeapMalloc.cpp" ]
   }
+
+  cflags = [ "-Wconversion" ]
 }

src/platform/Zephyr/DiagnosticDataProviderImpl.cpp

@@ -226,7 +226,7 @@ CHIP_ERROR DiagnosticDataProviderImpl::GetTotalOperationalHours(uint32_t & total
 
     ReturnErrorOnFailure(ConfigurationMgr().GetTotalOperationalHours(reinterpret_cast<uint32_t &>(totalHours)));
 
-    totalOperationalHours = totalHours + deltaTime < UINT32_MAX ? totalHours + deltaTime : UINT32_MAX;
+    totalOperationalHours = static_cast<uint32_t>(totalHours + deltaTime < UINT32_MAX ? totalHours + deltaTime : UINT32_MAX);
 
     return CHIP_NO_ERROR;
 }

src/platform/Zephyr/PlatformManagerImpl.cpp

@@ -27,6 +27,7 @@
 
 #include <platform/internal/CHIPDeviceLayerInternal.h>
 
+#include <lib/support/SafeInt.h>
 #include <lib/support/logging/CHIPLogging.h>
 #include <platform/PlatformManager.h>
 #include <platform/Zephyr/DiagnosticDataProviderImpl.h>
@@ -48,11 +49,20 @@ static k_timer sOperationalHoursSavingTimer;
 static int app_entropy_source(void * data, unsigned char * output, size_t len, size_t * olen)
 {
     const struct device * entropy = DEVICE_DT_GET(DT_CHOSEN(zephyr_entropy));
-    int ret                       = entropy_get_entropy(entropy, output, len);
+    uint16_t clampedLen;
+    if (CanCastTo<uint16_t>(len))
+    {
+        clampedLen = static_cast<uint16_t>(len);
+    }
+    else
+    {
+        clampedLen = UINT16_MAX;
+    }
+    int ret = entropy_get_entropy(entropy, output, clampedLen);
 
     if (ret == 0)
     {
-        *olen = len;
+        *olen = clampedLen;
     }
     else
     {
@@ -85,7 +95,7 @@ void PlatformManagerImpl::UpdateOperationalHours(intptr_t arg)
     if (ConfigurationMgr().GetTotalOperationalHours(reinterpret_cast<uint32_t &>(totalOperationalHours)) == CHIP_NO_ERROR)
     {
         ConfigurationMgr().StoreTotalOperationalHours(
-            totalOperationalHours + deltaTime < UINT32_MAX ? totalOperationalHours + deltaTime : UINT32_MAX);
+            static_cast<uint32_t>(totalOperationalHours + deltaTime < UINT32_MAX ? totalOperationalHours + deltaTime : UINT32_MAX));
         sInstance.mSavedOperationalHoursSinceBoot = upTimeH;
     }
     else

src/platform/nrfconnect/BUILD.gn

@@ -114,4 +114,6 @@ static_library("nrfconnect") {
   if (chip_malloc_sys_heap) {
     sources += [ "../Zephyr/SysHeapMalloc.cpp" ]
   }
+
+  cflags = [ "-Wconversion" ]
 }

src/platform/nrfconnect/OTAImageProcessorImpl.cpp

@@ -164,8 +164,16 @@ CHIP_ERROR OTAImageProcessorImpl::ProcessBlock(ByteSpan & aBlock)
     if (error == CHIP_NO_ERROR)
     {
         // DFU target library buffers data internally, so do not clone the block data.
-        error = System::MapErrorZephyr(dfu_multi_image_write(mParams.downloadedBytes, aBlock.data(), aBlock.size()));
-        mParams.downloadedBytes += aBlock.size();
+        if (mParams.downloadedBytes > std::numeric_limits<size_t>::max())
+        {
+            error = CHIP_ERROR_BUFFER_TOO_SMALL;
+        }
+        else
+        {
+            error = System::MapErrorZephyr(
+                dfu_multi_image_write(static_cast<size_t>(mParams.downloadedBytes), aBlock.data(), aBlock.size()));
+            mParams.downloadedBytes += aBlock.size();
+        }
     }
 
     // Report the result back to the downloader asynchronously.

src/platform/nrfconnect/wifi/NrfWiFiDriver.cpp

@@ -48,7 +48,7 @@ bool NrfWiFiDriver::WiFiNetworkIterator::Next(Network & item)
     }
 
     memcpy(item.networkID, mDriver->mStagingNetwork.ssid, mDriver->mStagingNetwork.ssidLen);
-    item.networkIDLen = mDriver->mStagingNetwork.ssidLen;
+    item.networkIDLen = static_cast<uint8_t>(mDriver->mStagingNetwork.ssidLen);
     item.connected    = false;
 
     mExhausted = true;

src/platform/nrfconnect/wifi/WiFiManager.cpp

@@ -252,8 +252,8 @@ CHIP_ERROR WiFiManager::GetWiFiInfo(WiFiInfo & info) const
         info.mBssId        = ByteSpan(mac_string_buf, sizeof(mac_string_buf));
         info.mSecurityType = static_cast<uint8_t>(status.security);
         info.mWiFiVersion  = static_cast<uint8_t>(status.link_mode);
-        info.mRssi         = status.rssi;
-        info.mChannel      = status.channel;
+        info.mRssi         = static_cast<int8_t>(status.rssi);
+        info.mChannel      = static_cast<uint16_t>(status.channel);
         info.mSsidLen      = status.ssid_len;
         memcpy(info.mSsid, status.ssid, status.ssid_len);
 
@@ -291,12 +291,12 @@ void WiFiManager::ScanResultHandler(uint8_t * data)
         if (scanResult->rssi > Instance().mWiFiParams.mRssi)
         {
             Instance().ClearStationProvisioningData();
-            Instance().mWiFiParams.mParams.ssid_length = Instance().mWantedNetwork.ssidLen;
+            Instance().mWiFiParams.mParams.ssid_length = static_cast<uint8_t>(Instance().mWantedNetwork.ssidLen);
             Instance().mWiFiParams.mParams.ssid        = Instance().mWantedNetwork.ssid;
             // Fallback to the WIFI_SECURITY_TYPE_PSK if the security is unknown
             Instance().mWiFiParams.mParams.security =
                 scanResult->security <= WIFI_SECURITY_TYPE_MAX ? scanResult->security : WIFI_SECURITY_TYPE_PSK;
-            Instance().mWiFiParams.mParams.psk_length = Instance().mWantedNetwork.passLen;
+            Instance().mWiFiParams.mParams.psk_length = static_cast<uint8_t>(Instance().mWantedNetwork.passLen);
 
             // If the security is none, WiFi driver expects the psk to be nullptr
             if (Instance().mWiFiParams.mParams.security == WIFI_SECURITY_TYPE_NONE)