Core/Unit: prevent m_extraAttacks underflow. Fixes a freeze with SPELL_EFFECT_ADD_EXTRA_ATTACKS

5 files changed, 14 insertions, 7 deletions

diff --git a/src/server/game/Entities/Player/Player.cpp b/src/server/game/Entities/Player/Player.cpp
index 6f47595e4d2..dff6f8c0478 100644
--- a/src/server/game/Entities/Player/Player.cpp
+++ b/src/server/game/Entities/Player/Player.cpp
@@ -8002,7 +8002,7 @@ void Player::CastItemCombatSpell(DamageInfo const& damageInfo, Item* item, ItemT
             }
 
             // not allow proc extra attack spell at extra attack
-            if (m_extraAttacks && spellInfo->HasEffect(SPELL_EFFECT_ADD_EXTRA_ATTACKS))
+            if (HasExtraAttacksPending() && spellInfo->HasEffect(SPELL_EFFECT_ADD_EXTRA_ATTACKS))
                 return;
 
             float chance = (float)spellInfo->ProcChance;
diff --git a/src/server/game/Entities/Unit/Unit.cpp b/src/server/game/Entities/Unit/Unit.cpp
index c06bcc891b2..1c1db83fb62 100644
--- a/src/server/game/Entities/Unit/Unit.cpp
+++ b/src/server/game/Entities/Unit/Unit.cpp
@@ -2088,11 +2088,13 @@ void Unit::AttackerStateUpdate(Unit* victim, WeaponAttackType attType, bool extr
 
 void Unit::HandleProcExtraAttackFor(Unit* victim)
 {
-    while (m_extraAttacks)
+    while (m_extraAttacks > 0)
     {
         AttackerStateUpdate(victim, BASE_ATTACK, true);
         --m_extraAttacks;
     }
+
+    m_extraAttacks = 0;
 }
 
 MeleeHitOutcome Unit::RollMeleeOutcomeAgainst(Unit const* victim, WeaponAttackType attType) const
diff --git a/src/server/game/Entities/Unit/Unit.h b/src/server/game/Entities/Unit/Unit.h
index 525d0d54ecb..aee3d783868 100644
--- a/src/server/game/Entities/Unit/Unit.h
+++ b/src/server/game/Entities/Unit/Unit.h
@@ -1296,7 +1296,10 @@ class TC_GAME_API Unit : public WorldObject
         bool IsWithinMeleeRange(Unit const* obj) const;
         float GetMeleeRange(Unit const* target) const;
         void GetRandomContactPoint(const Unit* target, float &x, float &y, float &z, float distance2dMin, float distance2dMax) const;
-        uint32 m_extraAttacks;
+
+        bool HasExtraAttacksPending() const { return m_extraAttacks > 0; }
+        void SetExtraAttacks(uint32 val) { m_extraAttacks = static_cast<int32>(val); }
+
         bool m_canDualWield;
 
         void _addAttacker(Unit* pAttacker);                  // must be called only from Unit::Attack(Unit*)
@@ -2285,6 +2288,8 @@ class TC_GAME_API Unit : public WorldObject
         uint32 m_lastManaUse;                               // msecs
         TimeTrackerSmall m_movesplineTimer;
 
+        int32 m_extraAttacks;
+
         Diminishing m_Diminishing;
         // Manage all Units that are threatened by us
         HostileRefManager m_HostileRefManager;
diff --git a/src/server/game/Spells/Spell.cpp b/src/server/game/Spells/Spell.cpp
index f072d71d9ff..9b21ea4c5fb 100644
--- a/src/server/game/Spells/Spell.cpp
+++ b/src/server/game/Spells/Spell.cpp
@@ -3498,12 +3498,12 @@ void Spell::_handle_finish_phase()
             m_caster->m_playerMovingMe->GainSpellComboPoints(m_comboPointGain);
     }
 
-    if (m_caster->m_extraAttacks && m_spellInfo->HasEffect(SPELL_EFFECT_ADD_EXTRA_ATTACKS))
+    if (m_caster->HasExtraAttacksPending() && m_spellInfo->HasEffect(SPELL_EFFECT_ADD_EXTRA_ATTACKS))
     {
         if (Unit* victim = ObjectAccessor::GetUnit(*m_caster, m_targets.GetOrigUnitTargetGUID()))
             m_caster->HandleProcExtraAttackFor(victim);
         else
-            m_caster->m_extraAttacks = 0;
+            m_caster->SetExtraAttacks(0);
     }
 
     // Handle procs on finish
diff --git a/src/server/game/Spells/SpellEffects.cpp b/src/server/game/Spells/SpellEffects.cpp
index 1b570e7778c..9867b25259b 100644
--- a/src/server/game/Spells/SpellEffects.cpp
+++ b/src/server/game/Spells/SpellEffects.cpp
@@ -4495,10 +4495,10 @@ void Spell::EffectAddExtraAttacks(SpellEffIndex effIndex)
     if (!unitTarget || !unitTarget->IsAlive())
         return;
 
-    if (unitTarget->m_extraAttacks)
+    if (unitTarget->HasExtraAttacksPending())
         return;
 
-    unitTarget->m_extraAttacks = damage;
+    unitTarget->SetExtraAttacks(damage);
 
     ExecuteLogEffectExtraAttacks(effIndex, unitTarget, damage);
 }