Check that stores are permitted by the pointer's storage access.

Fixes #1533.

src/proc/mod.rs

@@ -184,6 +184,21 @@ impl super::TypeInner {
  }
 }
 
+impl super::StorageClass {
+ pub fn access(self) -> crate::StorageAccess {
+ use crate::StorageAccess as Sa;
+ match self {
+ crate::StorageClass::Function |
+ crate::StorageClass::Private |
+ crate::StorageClass::WorkGroup => Sa::LOAD | Sa::STORE,
+ crate::StorageClass::Uniform => Sa::LOAD,
+ crate::StorageClass::Storage { access } => access,
+ crate::StorageClass::Handle => Sa::LOAD,
+ crate::StorageClass::PushConstant => Sa::LOAD,
+ }
+ }
+}
+
 impl super::MathFunction {
  pub fn argument_count(&self) -> usize {
  match *self {

src/valid/function.rs

@@ -606,10 +606,11 @@ impl super::Validator {
  }
  _ => {}
  }
- let good = match *context
- .resolve_pointer_type(pointer)
- .map_err(|e| e.with_span())?
- {
+
+ let pointer_ty = context.resolve_pointer_type(pointer)
+ .map_err(|e| e.with_span())?;
+
+ let good = match *pointer_ty {
  Ti::Pointer { base, class: _ } => match context.types[base].inner {
  Ti::Atomic { kind, width } => *value_ty == Ti::Scalar { kind, width },
  ref other => value_ty == other,
@@ -634,6 +635,14 @@ impl super::Validator {
  .with_handle(pointer, context.expressions)
  .with_handle(value, context.expressions));
  }
+
+ if let Some(class) = pointer_ty.pointer_class() {
+ if !class.access().contains(crate::StorageAccess::STORE) {
+ return Err(FunctionError::InvalidStorePointer(pointer)
+ .with_span_static(context.expressions.get_span(pointer),
+ "writing to this location is not permitted"));
+ }
+ }
  }
  S::ImageStore {
  image,

tests/wgsl-errors.rs

@@ -1029,3 +1029,46 @@ fn missing_default_case() {
  )
  }
 }
+
+#[test]
+fn wrong_access_mode() {
+ // The assignments to `global.i` should be forbidden, because they are in
+ // variables whose access mode is `read`, not `read_write`.
+ check_validation_error! {
+ "
+ [[block]]
+ struct Globals {
+ i: i32;
+ };
+
+ [[group(0), binding(0)]]
+ var<storage> globals: Globals;
+
+ fn store(v: i32) {
+ globals.i = v;
+ }
+ ",
+ "
+ [[block]]
+ struct Globals {
+ i: i32;
+ };
+
+ [[group(0), binding(0)]]
+ var<uniform> globals: Globals;
+
+ fn store(v: i32) {
+ globals.i = v;
+ }
+ ":
+ Err(
+ naga::valid::ValidationError::Function {
+ name,
+ error: naga::valid::FunctionError::InvalidStorePointer(_),
+ ..
+ },
+ )
+ if name == "store"
+ }
+}
+