vm: clear altstack on CALL, fix #1158

neo-vm doesn't copy altstack on CALL, so it effectively is cleared. But we
need to copy things back on return if there are any.
This commit is contained in:
Roman Khimov 2020-07-16 11:47:42 +03:00
parent 38c195fea9
commit 3d62db4f34

View file

@ -258,8 +258,9 @@ func (v *VM) Load(prog []byte) {
func (v *VM) LoadScript(b []byte) {
ctx := NewContext(b)
ctx.estack = v.estack
ctx.astack = v.astack
ctx.astack = v.newItemStack("alt")
v.istack.PushVal(ctx)
v.astack = ctx.astack
}
// loadScriptWithHash if similar to the LoadScript method, but it also loads
@ -1138,6 +1139,8 @@ func (v *VM) execute(ctx *Context, op opcode.Opcode, parameter []byte) (err erro
newCtx := ctx.Copy()
newCtx.rvcount = -1
newCtx.astack = v.newItemStack("alt")
v.astack = newCtx.astack
v.istack.PushVal(newCtx)
offset := v.getJumpOffset(newCtx, parameter, 0)
@ -1202,8 +1205,15 @@ func (v *VM) execute(ctx *Context, op opcode.Opcode, parameter []byte) (err erro
newEstack.Push(elem)
}
v.estack = newEstack
v.astack = v.Context().astack
}
newAstack := v.Context().astack
if rvcount == -1 && newAstack != oldCtx.astack {
for i := oldCtx.astack.Len(); i > 0; i-- {
elem := oldCtx.astack.RemoveAt(i - 1)
newAstack.Push(elem)
}
}
v.astack = newAstack
case opcode.CHECKSIG, opcode.VERIFY:
var hashToCheck []byte