Validate item modifier ranges

Source/inv.cpp

@@ -1746,6 +1746,22 @@ bool CanPut(Point position)
 	return true;
 }
 
+int16_t ClampToHit(const Item &item, int16_t toHit)
+{
+	if (toHit < item._iPLToHit || toHit > 51)
+		return item._iPLToHit;
+
+	return toHit;
+}
+
+uint8_t ClampMaxDam(const Item &item, uint8_t maxDam)
+{
+	if (maxDam < item._iMaxDam || maxDam - item._iMinDam > 30)
+		return item._iMaxDam;
+
+	return maxDam;
+}
+
 int SyncDropItem(Point position, _item_indexes idx, uint16_t icreateinfo, int iseed, int id, int dur, int mdur, int ch, int mch, int ivalue, uint32_t ibuff, int toHit, int maxDam)
 {
 	if (ActiveItemCount >= MAXITEMS)
@@ -1756,13 +1772,13 @@ int SyncDropItem(Point position, _item_indexes idx, uint16_t icreateinfo, int is
 	RecreateItem(*MyPlayer, item, idx, icreateinfo, iseed, ivalue, (ibuff & CF_HELLFIRE) != 0);
 	if (id != 0)
 		item._iIdentified = true;
-	item._iDurability = dur;
 	item._iMaxDur = mdur;
-	item._iCharges = ch;
-	item._iMaxCharges = mch;
+	item._iDurability = clamp<int>(dur, 1, item._iMaxDur);
+	item._iMaxCharges = clamp<int>(mch, 0, item._iMaxCharges);
+	item._iCharges = clamp<int>(ch, 0, item._iMaxCharges);
 	if (gbIsHellfire) {
-		item._iPLToHit = toHit;
-		item._iMaxDam = maxDam;
+		item._iPLToHit = ClampToHit(item, toHit);
+		item._iMaxDam = ClampMaxDam(item, maxDam);
 	}
 	item.dwBuff = ibuff;
 

Source/inv.h

@@ -219,6 +219,8 @@ void SyncGetItem(Point position, uint32_t iseed, _item_indexes idx, uint16_t ci)
  */
 bool CanPut(Point position);
 
+int16_t ClampToHit(const Item &item, int16_t toHit);
+uint8_t ClampMaxDam(const Item &item, uint8_t maxDam);
 int SyncDropItem(Point position, _item_indexes idx, uint16_t icreateinfo, int iseed, int id, int dur, int mdur, int ch, int mch, int ivalue, uint32_t ibuff, int toHit, int maxDam);
 int SyncDropEar(Point position, uint16_t icreateinfo, uint32_t iseed, uint8_t cursval, string_view heroname);
 int8_t CheckInvHLight();

Source/msg.cpp

@@ -1033,13 +1033,13 @@ void RecreateItem(const Player &player, const TItem &messageItem, Item &item)
 	    SDL_SwapLE32(messageItem.dwSeed), SDL_SwapLE16(messageItem.wValue), (dwBuff & CF_HELLFIRE) != 0);
 	if (messageItem.bId != 0)
 		item._iIdentified = true;
-	item._iDurability = messageItem.bDur;
 	item._iMaxDur = messageItem.bMDur;
-	item._iCharges = messageItem.bCh;
-	item._iMaxCharges = messageItem.bMCh;
+	item._iDurability = clamp<int>(messageItem.bDur, 1, item._iMaxDur);
+	item._iMaxCharges = clamp<int>(messageItem.bMCh, 0, item._iMaxCharges);
+	item._iCharges = clamp<int>(messageItem.bCh, 0, item._iMaxCharges);
 	if (gbIsHellfire) {
-		item._iPLToHit = SDL_SwapLE16(messageItem.wToHit);
-		item._iMaxDam = SDL_SwapLE16(messageItem.wMaxDam);
+		item._iPLToHit = ClampToHit(item, SDL_SwapLE16(messageItem.wToHit));
+		item._iMaxDam = ClampMaxDam(item, SDL_SwapLE16(messageItem.wMaxDam));
 	}
 	item.dwBuff = dwBuff;
 }