Merge pull request #592 from markshannon/python-windows-import-root

taus-semmle · web-flow · commit a23f7a6b0e65 · 2018-12-04T11:11:59.000+01:00
Python: Fix up computation of import root path
diff --git a/python/ql/src/semmle/python/Files.qll b/python/ql/src/semmle/python/Files.qll
@@ -339,9 +339,21 @@ abstract class Container extends @container {
 
     /** Holds if this folder is the root folder for the standard library. */
     predicate isStdLibRoot(int major, int minor) {
-        allowable_version(major, minor) and
-        this.isImportRoot() and
-        this.getBaseName().regexpMatch("python" + major + "." + minor)
+        major = major_version() and minor = minor_version() and
+        this.isStdLibRoot()
+    }
+
+    /** Holds if this folder is the root folder for the standard library. */
+    predicate isStdLibRoot() {
+        /* Look for a standard lib module and find its import path
+         * We use `os` as it is the most likely to be imported and
+         * `tty` because it is small for testing.
+         */
+        exists(Module m |
+            m.getName() = "os" or m.getName() = "tty"
+            |
+            m.getFile().getImportRoot() = this
+        )
     }
 
     /** Gets the path element from which this container would be loaded. */
@@ -375,12 +387,6 @@ private string get_path(string name) {
     py_flags_versioned(name, result, _)
 }
 
-private predicate allowable_version(int major, int minor) {
-    major = 2 and minor in [6..7]
-    or
-    major = 3 and minor in [3..6]
-}
-
 class Location extends @location {
 
     /** Gets the file for this location */
diff --git a/python/ql/src/semmle/python/Module.qll b/python/ql/src/semmle/python/Module.qll
@@ -158,7 +158,7 @@ class Module extends Module_, Scope, AstNode {
 
     /** Holds if this module is in the standard library */
     predicate inStdLib() {
-        this.inStdLib(_, _)
+        this.getLoadPath().isStdLibRoot()
     }
 
     override
diff --git a/python/ql/src/semmle/python/dependencies/TechInventory.qll b/python/ql/src/semmle/python/dependencies/TechInventory.qll
@@ -50,7 +50,7 @@ class DistPackage extends ExternalPackage {
             parent = this.(ModuleObject).getPath().getParent() and
             parent.isImportRoot() and
             /* Not in standard library */
-            not parent.isStdLibRoot(_, _) and
+            not parent.isStdLibRoot() and
             /* Not in the source */
             not exists(parent.getRelativePath())
         )
diff --git a/python/ql/test/library-tests/taint/exception_traceback/test.py b/python/ql/test/library-tests/taint/exception_traceback/test.py
@@ -28,3 +28,7 @@ def foo():
 
 
 foo()
+
+
+#For test to find stdlib
+import os

Original file line number	Diff line number	Diff line change
`@@ -158,7 +158,7 @@ class Module extends Module_, Scope, AstNode {`
`158`	`158`
`159`	`159`	`/** Holds if this module is in the standard library */`
`160`	`160`	`predicate inStdLib() {`
`161`		`- this.inStdLib(_, _)`
	`161`	`+ this.getLoadPath().isStdLibRoot()`
`162`	`162`	`}`
`163`	`163`
`164`	`164`	`override`
Original file line number	Diff line number	Diff line change
`@@ -50,7 +50,7 @@ class DistPackage extends ExternalPackage {`
`50`	`50`	`parent = this.(ModuleObject).getPath().getParent() and`
`51`	`51`	`parent.isImportRoot() and`
`52`	`52`	`/* Not in standard library */`
`53`		`- not parent.isStdLibRoot(_, _) and`
	`53`	`+ not parent.isStdLibRoot() and`
`54`	`54`	`/* Not in the source */`
`55`	`55`	`not exists(parent.getRelativePath())`
`56`	`56`	`)`