wazevo: adds 16 bytes to the new stack size (#1823)

Signed-off-by: Takeshi Yoneda <[email protected]>
tetratelabs · Oct 31, 2023 · 546af90 · 546af90
1 parent a4df8d3
commit 546af90
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Showing 2 changed files with 2 additions and 3 deletions.
diff --git a/internal/engine/wazevo/call_engine.go b/internal/engine/wazevo/call_engine.go
@@ -400,7 +400,6 @@ const callStackCeiling = uintptr(5000000) // in uint64 (8 bytes) == 40000000 byt
 func (c *callEngine) growStackWithGuarded() (newSP uintptr, err error) {
 	if wazevoapi.StackGuardCheckEnabled {
 		wazevoapi.CheckStackGuardPage(c.stack)
-		c.execCtx.stackGrowRequiredSize += wazevoapi.StackGuardCheckGuardPageSize
 	}
 	newSP, err = c.growStack()
 	if err != nil {
@@ -420,7 +419,7 @@ func (c *callEngine) growStack() (newSP uintptr, err error) {
 		return
 	}
 
-	newLen := 2*currentLen + c.execCtx.stackGrowRequiredSize
+	newLen := 2*currentLen + c.execCtx.stackGrowRequiredSize + 16 // Stack might be aligned to 16 bytes, so add 16 bytes just in case.
 	newStack := make([]byte, newLen)
 
 	relSp := c.stackTop - uintptr(unsafe.Pointer(c.execCtx.stackPointerBeforeGoCall))

diff --git a/internal/engine/wazevo/call_engine_test.go b/internal/engine/wazevo/call_engine_test.go
@@ -37,7 +37,7 @@ func TestCallEngine_growStack(t *testing.T) {
 		}
 		newSP, err := c.growStack()
 		require.NoError(t, err)
-		require.Equal(t, 160+32*2, len(c.stack))
+		require.Equal(t, 160+32*2+16, len(c.stack))
 
 		require.True(t, c.stackTop%16 == 0)
 		require.Equal(t, &c.stack[0], c.execCtx.stackBottomPtr)