fixed the bug with numpy() return values sharing memory and being wri…

…teable
jonasrauber · Feb 12, 2020 · 19bce20 · 19bce20
1 parent 94ccc1b
commit 19bce20
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Showing 4 changed files with 21 additions and 4 deletions.
diff --git a/eagerpy/tensor/jax.py b/eagerpy/tensor/jax.py
@@ -99,7 +99,9 @@ def _get_subkey(cls) -> Any:
         return subkey
 
     def numpy(self) -> Any:
-        return onp.asarray(self.raw)
+        a = onp.asarray(self.raw)
+        assert a.flags.writeable is False
+        return a
 
     def item(self) -> Union[int, float, bool]:
         return self.raw.item()  # type: ignore

diff --git a/eagerpy/tensor/numpy.py b/eagerpy/tensor/numpy.py
@@ -47,7 +47,12 @@ def raw(self) -> "np.ndarray":  # type: ignore
         return super().raw
 
     def numpy(self: TensorType) -> Any:
-        return self.raw
+        a = self.raw.view()
+        if a.flags.writeable:
+            # without the check, we would attempt to set it on array
+            # scalars, and that would fail
+            a.flags.writeable = False
+        return a
 
     def item(self) -> Union[int, float, bool]:
         return self.raw.item()  # type: ignore

diff --git a/eagerpy/tensor/pytorch.py b/eagerpy/tensor/pytorch.py
@@ -62,7 +62,12 @@ def tanh(self: TensorType) -> TensorType:
         return type(self)(torch.tanh(self.raw))
 
     def numpy(self: TensorType) -> Any:
-        return self.raw.detach().cpu().numpy()
+        a = self.raw.detach().cpu().numpy()
+        if a.flags.writeable:
+            # without the check, we would attempt to set it on array
+            # scalars, and that would fail
+            a.flags.writeable = False
+        return a
 
     def item(self) -> Union[int, float, bool]:
         return self.raw.item()

diff --git a/eagerpy/tensor/tensorflow.py b/eagerpy/tensor/tensorflow.py
@@ -94,7 +94,12 @@ def raw(self) -> "tf.Tensor":  # type: ignore
         return super().raw
 
     def numpy(self: TensorType) -> Any:
-        return self.raw.numpy()
+        a = self.raw.numpy()
+        if a.flags.writeable:
+            # without the check, we would attempt to set it on array
+            # scalars, and that would fail
+            a.flags.writeable = False
+        return a
 
     def item(self: TensorType) -> Union[int, float, bool]:
         return self.numpy().item()  # type: ignore