Python points-to: Fix up some oddities with nested from ... import *.

markshannon · markshannon · commit bcfe209849a5 · 2019-06-24T12:19:11.000+01:00
diff --git a/python/ql/src/semmle/python/objects/Modules.qll b/python/ql/src/semmle/python/objects/Modules.qll
@@ -175,15 +175,9 @@ class PackageObjectInternal extends ModuleObjectInternal, TPackageObject {
     pragma [noinline] override predicate attribute(string name, ObjectInternal value, CfgOrigin origin) {
         this.getInitModule().attribute(name, value, origin)
         or
-        exists(Module init |
-            init = this.getSourceModule() and
-            (
-                /* There is no variable shadowing the name of the child module */
-                not exists(EssaVariable var | var.getAUse() = init.getANormalExit() and var.getSourceVariable().getName() = name)
-                or
-                /* The variable shadowing the name of the child module is undefined at exit */
-                ModuleAttributes::pointsToAtExit(init, name, ObjectInternal::undefined(), _)
-            ) and
+        exists(ModuleObjectInternal init |
+            init = this.getInitModule() and
+            InterModulePointsTo::moduleExportsBoolean(init, name) = false and
             not name = "__init__" and
             value = this.submodule(name) and
             origin = CfgOrigin::fromObject(value)
@@ -249,6 +243,7 @@ class PythonModuleObjectInternal extends ModuleObjectInternal, TPythonModule {
     }
 
     pragma [noinline] override predicate attribute(string name, ObjectInternal value, CfgOrigin origin) {
+        value != ObjectInternal::undefined() and
         ModuleAttributes::pointsToAtExit(this.getSourceModule(), name, value, origin)
     }
 
diff --git a/python/ql/src/semmle/python/pointsto/PointsTo.qll b/python/ql/src/semmle/python/pointsto/PointsTo.qll
@@ -594,7 +594,7 @@ cached module PointsToInternal {
 
 }
 
-private module InterModulePointsTo {
+module InterModulePointsTo {
 
     pragma [noinline]
     predicate import_points_to(ControlFlowNode f, PointsToContext context, ObjectInternal value, ControlFlowNode origin) {

Original file line number	Diff line number	Diff line change
`@@ -594,7 +594,7 @@ cached module PointsToInternal {`
`594`	`594`
`595`	`595`	`}`
`596`	`596`
`597`		`-private module InterModulePointsTo {`
	`597`	`+module InterModulePointsTo {`
`598`	`598`
`599`	`599`	`pragma [noinline]`
`600`	`600`	`predicate import_points_to(ControlFlowNode f, PointsToContext context, ObjectInternal value, ControlFlowNode origin) {`