Bug 1665816 - CSSOM should respect rule-level property restrictions. r=jwatt

Differential Revision: https://phabricator.services.mozilla.com/D90729

dom/base/nsAttrValue.cpp

@@ -22,6 +22,7 @@
 #include "mozilla/ServoUtils.h"
 #include "mozilla/ShadowParts.h"
 #include "mozilla/DeclarationBlock.h"
+#include "mozilla/dom/CSSRuleBinding.h"
 #include "nsContentUtils.h"
 #include "nsReadableUtils.h"
 #include "nsHTMLCSSStyleSheet.h"
@@ -1732,10 +1733,10 @@ bool nsAttrValue::ParseStyleAttribute(const nsAString& aString,
 
   nsCOMPtr<nsIReferrerInfo> referrerInfo =
       dom::ReferrerInfo::CreateForInternalCSSResources(ownerDoc);
-  RefPtr<URLExtraData> data =
+  auto data = MakeRefPtr<URLExtraData>(baseURI, referrerInfo, principal);
-      new URLExtraData(baseURI, referrerInfo, principal);
   RefPtr<DeclarationBlock> decl = DeclarationBlock::FromCssText(
-      aString, data, ownerDoc->GetCompatibilityMode(), ownerDoc->CSSLoader());
+      aString, data, ownerDoc->GetCompatibilityMode(), ownerDoc->CSSLoader(),
+      dom::CSSRule_Binding::STYLE_RULE);
   if (!decl) {
     return false;
   }

dom/canvas/CanvasRenderingContext2D.cpp

@@ -2182,14 +2182,9 @@ void CanvasRenderingContext2D::SetShadowColor(const nsAString& aShadowColor) {
 static already_AddRefed<RawServoDeclarationBlock> CreateDeclarationForServo(
     nsCSSPropertyID aProperty, const nsAString& aPropertyValue,
     Document* aDocument) {
-  nsCOMPtr<nsIReferrerInfo> referrerInfo =
+  ServoCSSParser::ParsingEnvironment env{aDocument->DefaultStyleAttrURLData(),
-      ReferrerInfo::CreateForInternalCSSResources(aDocument);
+                                         aDocument->GetCompatibilityMode(),
-
+                                         aDocument->CSSLoader()};
-  RefPtr<URLExtraData> data = new URLExtraData(
-      aDocument->GetDocBaseURI(), referrerInfo, aDocument->NodePrincipal());
-
-  ServoCSSParser::ParsingEnvironment env(
-      data, aDocument->GetCompatibilityMode(), aDocument->CSSLoader());
   RefPtr<RawServoDeclarationBlock> servoDeclarations =
       ServoCSSParser::ParseProperty(aProperty, aPropertyValue, env);
 
@@ -2203,9 +2198,9 @@ static already_AddRefed<RawServoDeclarationBlock> CreateDeclarationForServo(
   if (aProperty == eCSSProperty_font) {
     const nsCString normalString = "normal"_ns;
     Servo_DeclarationBlock_SetPropertyById(
-        servoDeclarations, eCSSProperty_line_height, &normalString, false, data,
+        servoDeclarations, eCSSProperty_line_height, &normalString, false,
-        ParsingMode::Default, aDocument->GetCompatibilityMode(),
+        env.mUrlExtraData, ParsingMode::Default, env.mCompatMode, env.mLoader,
-        aDocument->CSSLoader(), {});
+        env.mRuleType, {});
   }
 
   return servoDeclarations.forget();

dom/svg/SVGElement.cpp

@@ -8,6 +8,7 @@
 
 #include "mozilla/dom/MutationEventBinding.h"
 #include "mozilla/dom/MutationObservers.h"
+#include "mozilla/dom/CSSRuleBinding.h"
 #include "mozilla/dom/SVGElementBinding.h"
 #include "mozilla/dom/SVGGeometryElement.h"
 #include "mozilla/dom/SVGLengthBinding.h"
@@ -1148,12 +1149,13 @@ void MappedAttrParser::ParseMappedAttrValue(nsAtom* aMappedAttrName,
     nsCOMPtr<nsIReferrerInfo> referrerInfo =
         ReferrerInfo::CreateForSVGResources(mElement->OwnerDoc());
 
-    RefPtr<URLExtraData> data =
+    auto data = MakeRefPtr<URLExtraData>(mBaseURI, referrerInfo,
-        new URLExtraData(mBaseURI, referrerInfo, mElement->NodePrincipal());
+                                         mElement->NodePrincipal());
     changed = Servo_DeclarationBlock_SetPropertyById(
         mDecl->Raw(), propertyID, &value, false, data,
         ParsingMode::AllowUnitlessLength,
-        mElement->OwnerDoc()->GetCompatibilityMode(), mLoader, {});
+        mElement->OwnerDoc()->GetCompatibilityMode(), mLoader,
+        CSSRule_Binding::STYLE_RULE, {});
 
     // TODO(emilio): If we want to record these from CSSOM more generally, we
     // can pass the document use counters down the FFI call. For now manually

dom/xul/nsXULElement.cpp

@@ -14,6 +14,7 @@
 #include "nsIDOMXULSelectCntrlItemEl.h"
 #include "mozilla/dom/BindContext.h"
 #include "mozilla/dom/Document.h"
+#include "mozilla/dom/CSSRuleBinding.h"
 #include "mozilla/ClearOnShutdown.h"
 #include "mozilla/EventListenerManager.h"
 #include "mozilla/EventStateManager.h"
@@ -1506,13 +1507,12 @@ nsresult nsXULPrototypeElement::SetAttrAt(uint32_t aPos,
     // as has been discussed, the CSP should be checked here to see if
     // inline styles are allowed to be applied.
     // XXX No specific specs talk about xul and referrer policy, pass Unset
-    nsCOMPtr<nsIReferrerInfo> referrerInfo =
+    auto referrerInfo =
-        new ReferrerInfo(aDocumentURI, ReferrerPolicy::_empty);
+        MakeRefPtr<ReferrerInfo>(aDocumentURI, ReferrerPolicy::_empty);
-
+    auto data = MakeRefPtr<URLExtraData>(aDocumentURI, referrerInfo, principal);
-    RefPtr<URLExtraData> data =
-        new URLExtraData(aDocumentURI, referrerInfo, principal);
     RefPtr<DeclarationBlock> declaration = DeclarationBlock::FromCssText(
-        aValue, data, eCompatibility_FullStandards, nullptr);
+        aValue, data, eCompatibility_FullStandards, nullptr,
+        CSSRule_Binding::STYLE_RULE);
     if (declaration) {
       mAttributes[aPos].mValue.SetTo(declaration.forget(), &aValue);
 

layout/style/CSSKeyframeRule.cpp

@@ -56,7 +56,7 @@ class CSSKeyframeDeclaration : public nsDOMCSSDeclaration {
   }
   ParsingEnvironment GetParsingEnvironment(
       nsIPrincipal* aSubjectPrincipal) const final {
-    return GetParsingEnvironmentForRule(mRule);
+    return GetParsingEnvironmentForRule(mRule, CSSRule_Binding::KEYFRAME_RULE);
   }
   Document* DocToUpdate() final { return nullptr; }
 

layout/style/CSSPageRule.cpp

@@ -73,7 +73,7 @@ nsresult CSSPageRuleDeclaration::SetCSSDeclaration(
 nsDOMCSSDeclaration::ParsingEnvironment
 CSSPageRuleDeclaration::GetParsingEnvironment(
     nsIPrincipal* aSubjectPrincipal) const {
-  return GetParsingEnvironmentForRule(Rule());
+  return GetParsingEnvironmentForRule(Rule(), CSSRule_Binding::PAGE_RULE);
 }
 
 // -- CSSPageRule --------------------------------------------------

layout/style/CSSStyleRule.cpp

@@ -83,7 +83,7 @@ Document* CSSStyleRuleDeclaration::DocToUpdate() { return nullptr; }
 nsDOMCSSDeclaration::ParsingEnvironment
 CSSStyleRuleDeclaration::GetParsingEnvironment(
     nsIPrincipal* aSubjectPrincipal) const {
-  return GetParsingEnvironmentForRule(Rule());
+  return GetParsingEnvironmentForRule(Rule(), CSSRule_Binding::STYLE_RULE);
 }
 
 // -- CSSStyleRule --------------------------------------------------

layout/style/DeclarationBlock.cpp

@@ -7,24 +7,12 @@
 #include "mozilla/DeclarationBlock.h"
 
 #include "mozilla/css/Rule.h"
-#include "mozilla/ServoBindings.h"
 
 #include "nsCSSProps.h"
 #include "nsIMemoryReporter.h"
 
 namespace mozilla {
 
-/* static */
-already_AddRefed<DeclarationBlock> DeclarationBlock::FromCssText(
-    const nsAString& aCssText, URLExtraData* aExtraData, nsCompatibility aMode,
-    css::Loader* aLoader) {
-  NS_ConvertUTF16toUTF8 value(aCssText);
-  RefPtr<RawServoDeclarationBlock> raw =
-      Servo_ParseStyleAttribute(&value, aExtraData, aMode, aLoader).Consume();
-  RefPtr<DeclarationBlock> decl = new DeclarationBlock(raw.forget());
-  return decl.forget();
-}
-
 MOZ_DEFINE_MALLOC_SIZE_OF(ServoDeclarationBlockMallocSizeOf)
 MOZ_DEFINE_MALLOC_ENCLOSING_SIZE_OF(ServoDeclarationBlockEnclosingSizeOf)
 

layout/style/DeclarationBlock.h

@@ -147,7 +147,13 @@ class DeclarationBlock final {
 
   static already_AddRefed<DeclarationBlock> FromCssText(
       const nsAString& aCssText, URLExtraData* aExtraData,
-      nsCompatibility aMode, css::Loader* aLoader);
+      nsCompatibility aMode, css::Loader* aLoader, uint16_t aRuleType) {
+    NS_ConvertUTF16toUTF8 value(aCssText);
+    RefPtr<RawServoDeclarationBlock> raw =
+        Servo_ParseStyleAttribute(&value, aExtraData, aMode, aLoader, aRuleType)
+            .Consume();
+    return MakeAndAddRef<DeclarationBlock>(raw.forget());
+  }
 
   RawServoDeclarationBlock* Raw() const { return mRaw; }
   RawServoDeclarationBlock* const* RefRaw() const {

layout/style/ServoCSSParser.cpp

@@ -38,7 +38,8 @@ already_AddRefed<RawServoDeclarationBlock> ServoCSSParser::ParseProperty(
   NS_ConvertUTF16toUTF8 value(aValue);
   return Servo_ParseProperty(
              aProperty, &value, aParsingEnvironment.mUrlExtraData, aParsingMode,
-             aParsingEnvironment.mCompatMode, aParsingEnvironment.mLoader)
+             aParsingEnvironment.mCompatMode, aParsingEnvironment.mLoader,
+             aParsingEnvironment.mRuleType)
       .Consume();
 }
 
@@ -80,7 +81,6 @@ already_AddRefed<URLExtraData> ServoCSSParser::GetURLExtraData(
 
 /* static */ ServoCSSParser::ParsingEnvironment
 ServoCSSParser::GetParsingEnvironment(Document* aDocument) {
-  return ParsingEnvironment(GetURLExtraData(aDocument),
+  return {GetURLExtraData(aDocument), aDocument->GetCompatibilityMode(),
-                            aDocument->GetCompatibilityMode(),
+          aDocument->CSSLoader()};
-                            aDocument->CSSLoader());
 }

layout/style/nsDOMCSSDeclaration.cpp

@@ -140,7 +140,8 @@ void nsDOMCSSDeclaration::SetCssText(const nsAString& aCssText,
   }
 
   RefPtr<DeclarationBlock> newdecl = DeclarationBlock::FromCssText(
-      aCssText, servoEnv.mUrlExtraData, servoEnv.mCompatMode, servoEnv.mLoader);
+      aCssText, servoEnv.mUrlExtraData, servoEnv.mCompatMode, servoEnv.mLoader,
+      servoEnv.mRuleType);
 
   aRv = SetCSSDeclaration(newdecl, &closureData);
 }
@@ -237,10 +238,17 @@ void nsDOMCSSDeclaration::RemoveProperty(const nsACString& aPropertyName,
 }
 
 /* static */ nsDOMCSSDeclaration::ParsingEnvironment
-nsDOMCSSDeclaration::GetParsingEnvironmentForRule(const css::Rule* aRule) {
+nsDOMCSSDeclaration::GetParsingEnvironmentForRule(const css::Rule* aRule,
-  StyleSheet* sheet = aRule ? aRule->GetStyleSheet() : nullptr;
+                                                  uint16_t aRuleType) {
+  if (!aRule) {
+    return {};
+  }
+
+  MOZ_ASSERT(aRule->Type() == aRuleType);
+
+  StyleSheet* sheet = aRule->GetStyleSheet();
   if (!sheet) {
-    return {nullptr, eCompatibility_FullStandards, nullptr};
+    return {};
   }
 
   if (Document* document = sheet->GetAssociatedDocument()) {
@@ -248,6 +256,7 @@ nsDOMCSSDeclaration::GetParsingEnvironmentForRule(const css::Rule* aRule) {
         sheet->URLData(),
         document->GetCompatibilityMode(),
         document->CSSLoader(),
+        aRuleType,
     };
   }
 
@@ -255,6 +264,7 @@ nsDOMCSSDeclaration::GetParsingEnvironmentForRule(const css::Rule* aRule) {
       sheet->URLData(),
       eCompatibility_FullStandards,
       nullptr,
+      aRuleType,
   };
 }
 
@@ -311,7 +321,8 @@ nsresult nsDOMCSSDeclaration::ParsePropertyValue(
       [&](DeclarationBlock* decl, ParsingEnvironment& env) {
         return Servo_DeclarationBlock_SetPropertyById(
             decl->Raw(), aPropID, &aPropValue, aIsImportant, env.mUrlExtraData,
-            ParsingMode::Default, env.mCompatMode, env.mLoader, closure);
+            ParsingMode::Default, env.mCompatMode, env.mLoader, env.mRuleType,
+            closure);
       });
 }
 
@@ -334,7 +345,7 @@ nsresult nsDOMCSSDeclaration::ParseCustomPropertyValue(
         return Servo_DeclarationBlock_SetProperty(
             decl->Raw(), &aPropertyName, &aPropValue, aIsImportant,
             env.mUrlExtraData, ParsingMode::Default, env.mCompatMode,
-            env.mLoader, closure);
+            env.mLoader, env.mRuleType, closure);
       });
 }
 

layout/style/nsDOMCSSDeclaration.h

@@ -125,25 +125,15 @@ class nsDOMCSSDeclaration : public nsICSSDeclaration {
   virtual void IndexedGetter(uint32_t aIndex, bool& aFound,
                              nsACString& aPropName) override;
 
-  virtual JSObject* WrapObject(JSContext* aCx,
+  JSObject* WrapObject(JSContext*, JS::Handle<JSObject*> aGivenProto) override;
-                               JS::Handle<JSObject*> aGivenProto) override;
 
   // Information needed to parse a declaration for Servo side.
   // Put this in public so other Servo parsing functions can reuse this.
   struct MOZ_STACK_CLASS ParsingEnvironment {
     RefPtr<mozilla::URLExtraData> mUrlExtraData;
-    nsCompatibility mCompatMode;
+    nsCompatibility mCompatMode = eCompatibility_FullStandards;
-    mozilla::css::Loader* mLoader;
+    mozilla::css::Loader* mLoader = nullptr;
-
+    uint16_t mRuleType{0};
-    ParsingEnvironment(mozilla::URLExtraData* aUrlData,
-                       nsCompatibility aCompatMode,
-                       mozilla::css::Loader* aLoader)
-        : mUrlExtraData(aUrlData), mCompatMode(aCompatMode), mLoader(aLoader) {}
-
-    ParsingEnvironment(already_AddRefed<mozilla::URLExtraData> aUrlData,
-                       nsCompatibility aCompatMode,
-                       mozilla::css::Loader* aLoader)
-        : mUrlExtraData(aUrlData), mCompatMode(aCompatMode), mLoader(aLoader) {}
   };
 
  protected:
@@ -189,8 +179,11 @@ class nsDOMCSSDeclaration : public nsICSSDeclaration {
 
   // An implementation for GetParsingEnvironment for callers wrapping a
   // css::Rule.
+  //
+  // The RuleType argument is just to avoid a virtual call, since all callers
+  // know it statically. Should be equal to aRule->Type().
   static ParsingEnvironment GetParsingEnvironmentForRule(
-      const mozilla::css::Rule* aRule);
+      const mozilla::css::Rule* aRule, uint16_t aRuleType);
 
   nsresult ParsePropertyValue(const nsCSSPropertyID aPropID,
                               const nsACString& aPropValue, bool aIsImportant,

layout/style/test/gtest/StyloParsingBench.cpp

@@ -50,6 +50,8 @@ static void ServoParsingBench(const StyleUseCounters* aCounters) {
   }
 }
 
+static constexpr uint16_t STYLE_RULE = 1;
+
 static void ServoSetPropertyByIdBench(const nsACString& css) {
   RefPtr<RawServoDeclarationBlock> block =
       Servo_DeclarationBlock_CreateEmpty().Consume();
@@ -64,7 +66,7 @@ static void ServoSetPropertyByIdBench(const nsACString& css) {
     Servo_DeclarationBlock_SetPropertyById(
         block, eCSSProperty_width, &css,
         /* is_important = */ false, data, ParsingMode::Default,
-        eCompatibility_FullStandards, nullptr, {});
+        eCompatibility_FullStandards, nullptr, STYLE_RULE, {});
   }
 }
 
@@ -82,7 +84,7 @@ static void ServoGetPropertyValueById() {
   Servo_DeclarationBlock_SetPropertyById(
       block, eCSSProperty_width, &css,
       /* is_important = */ false, data, ParsingMode::Default,
-      eCompatibility_FullStandards, nullptr, {});
+      eCompatibility_FullStandards, nullptr, STYLE_RULE, {});
 
   for (int i = 0; i < GETPROPERTY_REPETITIONS; i++) {
     DOMString value_;

servo/components/style/properties/declaration_block.rs

@@ -1263,11 +1263,12 @@ pub fn parse_style_attribute(
     url_data: &UrlExtraData,
     error_reporter: Option<&dyn ParseErrorReporter>,
     quirks_mode: QuirksMode,
+    rule_type: CssRuleType,
 ) -> PropertyDeclarationBlock {
     let context = ParserContext::new(
         Origin::Author,
         url_data,
-        Some(CssRuleType::Style),
+        Some(rule_type),
         ParsingMode::DEFAULT,
         quirks_mode,
         error_reporter,
@@ -1291,11 +1292,12 @@ pub fn parse_one_declaration_into(
     error_reporter: Option<&dyn ParseErrorReporter>,
     parsing_mode: ParsingMode,
     quirks_mode: QuirksMode,
+    rule_type: CssRuleType,
 ) -> Result<(), ()> {
     let context = ParserContext::new(
         Origin::Author,
         url_data,
-        Some(CssRuleType::Style),
+        Some(rule_type),
         parsing_mode,
         quirks_mode,
         error_reporter,

servo/components/style/properties/properties.mako.rs

@@ -542,10 +542,12 @@ impl NonCustomPropertyId {
         false
     }
 
-    fn allowed_in(self, context: &ParserContext) -> bool {
+    /// Returns whether a given rule allows a given property.
+    #[inline]
+    pub fn allowed_in_rule(self, rule_type: CssRuleType) -> bool {
         debug_assert!(
             matches!(
-                context.rule_type(),
+                rule_type,
                 CssRuleType::Keyframe | CssRuleType::Page | CssRuleType::Style
             ),
             "Declarations are only expected inside a keyframe, page, or style rule."
@@ -559,14 +561,16 @@ impl NonCustomPropertyId {
             "DISALLOWED_IN_PAGE_RULE",
             lambda p: not p.allowed_in_page_rule
         )}
-        match context.rule_type() {
+        match rule_type {
-            CssRuleType::Keyframe if DISALLOWED_IN_KEYFRAME_BLOCK.contains(self) => {
+            CssRuleType::Keyframe => !DISALLOWED_IN_KEYFRAME_BLOCK.contains(self),
-                return false;
+            CssRuleType::Page => !DISALLOWED_IN_PAGE_RULE.contains(self),
-            }
+            _ => true
-            CssRuleType::Page if DISALLOWED_IN_PAGE_RULE.contains(self) => {
+        }
-                return false;
+    }
-            }
+
-            _ => {}
+    fn allowed_in(self, context: &ParserContext) -> bool {
+        if !self.allowed_in_rule(context.rule_type()) {
+            return false;
         }
 
         self.allowed_in_ignoring_rule_type(context)

servo/components/style/stylesheets/mod.rs

@@ -299,7 +299,7 @@ impl CssRule {
 }
 
 #[allow(missing_docs)]
-#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+#[derive(Clone, Copy, Debug, Eq, FromPrimitive, PartialEq)]
 pub enum CssRuleType {
     // https://drafts.csswg.org/cssom/#the-cssrule-interface
     Style = 1,

servo/ports/geckolib/glue.rs

@@ -4050,12 +4050,19 @@ fn parse_property_into(
     data: *mut URLExtraData,
     parsing_mode: structs::ParsingMode,
     quirks_mode: QuirksMode,
+    rule_type: CssRuleType,
     reporter: Option<&dyn ParseErrorReporter>,
 ) -> Result<(), ()> {
     let value = unsafe { value.as_str_unchecked() };
     let url_data = unsafe { UrlExtraData::from_ptr_ref(&data) };
     let parsing_mode = ParsingMode::from_bits_truncate(parsing_mode);
 
+    if let Some(non_custom) = property_id.non_custom_id() {
+        if !non_custom.allowed_in_rule(rule_type) {
+            return Err(());
+        }
+    }
+
     parse_one_declaration_into(
         declarations,
         property_id,
@@ -4064,6 +4071,7 @@ fn parse_property_into(
         reporter,
         parsing_mode,
         quirks_mode,
+        rule_type,
     )
 }
 
@@ -4075,6 +4083,7 @@ pub extern "C" fn Servo_ParseProperty(
     parsing_mode: structs::ParsingMode,
     quirks_mode: nsCompatibility,
     loader: *mut Loader,
+    rule_type: u16,
 ) -> Strong<RawServoDeclarationBlock> {
     let id = get_property_id_from_nscsspropertyid!(property, Strong::null());
     let mut declarations = SourcePropertyDeclaration::new();
@@ -4086,6 +4095,7 @@ pub extern "C" fn Servo_ParseProperty(
         data,
         parsing_mode,
         quirks_mode.into(),
+        to_rule_type(rule_type),
         reporter.as_ref().map(|r| r as &dyn ParseErrorReporter),
     );
 
@@ -4215,6 +4225,7 @@ pub unsafe extern "C" fn Servo_ParseStyleAttribute(
     raw_extra_data: *mut URLExtraData,
     quirks_mode: nsCompatibility,
     loader: *mut Loader,
+    rule_type: u16,
 ) -> Strong<RawServoDeclarationBlock> {
     let global_style_data = &*GLOBAL_STYLE_DATA;
     let value = data.as_str_unchecked();
@@ -4225,6 +4236,7 @@ pub unsafe extern "C" fn Servo_ParseStyleAttribute(
         url_data,
         reporter.as_ref().map(|r| r as &dyn ParseErrorReporter),
         quirks_mode.into(),
+        to_rule_type(rule_type),
     )))
     .into_strong()
 }
@@ -4437,6 +4449,7 @@ fn set_property(
     parsing_mode: structs::ParsingMode,
     quirks_mode: QuirksMode,
     loader: *mut Loader,
+    rule_type: CssRuleType,
     before_change_closure: DeclarationBlockMutationClosure,
 ) -> bool {
     let mut source_declarations = SourcePropertyDeclaration::new();
@@ -4448,6 +4461,7 @@ fn set_property(
         data,
         parsing_mode,
         quirks_mode,
+        rule_type,
         reporter.as_ref().map(|r| r as &dyn ParseErrorReporter),
     );
 
@@ -4469,6 +4483,12 @@ fn set_property(
     )
 }
 
+#[inline]
+fn to_rule_type(ty: u16) -> CssRuleType {
+    use num_traits::FromPrimitive;
+    CssRuleType::from_u16(ty).unwrap_or(CssRuleType::Style)
+}
+
 #[no_mangle]
 pub unsafe extern "C" fn Servo_DeclarationBlock_SetProperty(
     declarations: &RawServoDeclarationBlock,
@@ -4479,6 +4499,7 @@ pub unsafe extern "C" fn Servo_DeclarationBlock_SetProperty(
     parsing_mode: structs::ParsingMode,
     quirks_mode: nsCompatibility,
     loader: *mut Loader,
+    rule_type: u16,
     before_change_closure: DeclarationBlockMutationClosure,
 ) -> bool {
     set_property(
@@ -4490,6 +4511,7 @@ pub unsafe extern "C" fn Servo_DeclarationBlock_SetProperty(
         parsing_mode,
         quirks_mode.into(),
         loader,
+        to_rule_type(rule_type),
         before_change_closure,
     )
 }
@@ -4521,6 +4543,7 @@ pub unsafe extern "C" fn Servo_DeclarationBlock_SetPropertyById(
     parsing_mode: structs::ParsingMode,
     quirks_mode: nsCompatibility,
     loader: *mut Loader,
+    rule_type: u16,
     before_change_closure: DeclarationBlockMutationClosure,
 ) -> bool {
     set_property(
@@ -4532,6 +4555,7 @@ pub unsafe extern "C" fn Servo_DeclarationBlock_SetPropertyById(
         parsing_mode,
         quirks_mode.into(),
         loader,
+        to_rule_type(rule_type),
         before_change_closure,
     )
 }
@@ -5274,6 +5298,7 @@ pub unsafe extern "C" fn Servo_CSSSupports2(
         DUMMY_URL_DATA,
         structs::ParsingMode_Default,
         QuirksMode::NoQuirks,
+        CssRuleType::Style,
         None,
     )
     .is_ok()

testing/web-platform/tests/css/cssom/cssimportrule.html

@@ -95,8 +95,8 @@
 
         test(function() {
             var ruleWithPage = ruleList[3];
-            ruleWithPage.style = "background-color: green;"
+            ruleWithPage.style = "margin-top: 10px;"
-            assert_equals(ruleWithPage.style.cssText, "background-color: green;");
+            assert_equals(ruleWithPage.style.cssText, "margin-top: 10px;");
         }, "CSSStyleDeclaration cssText attribute should be updated due to [PutForwards]");
 
         test(function() {

testing/web-platform/tests/css/cssom/rule-restrictions.html

@@ -0,0 +1,51 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>CSSOM Should correctly honor property restrictions</title>
+<link rel="author" title="Emilio Cobos Álvarez" href="mailto:emilio@crisal.io">
+<link rel="author" title="Mozilla" href="https://mozilla.org">
+<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1665816">
+<link rel="help" href="https://drafts.csswg.org/css-page-3/#conform-partial">
+<link rel="help" href="https://drafts.csswg.org/css-animations/#keyframes">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<style>
+  @page {
+    margin-top: 10px;
+    transform: scale(1);
+  }
+
+  @keyframes foo {
+    from {
+      margin-top: 10px;
+      animation-name: none;
+    }
+  }
+</style>
+<script>
+test(function() {
+  let rule = document.styleSheets[0].cssRules[0];
+  assert_equals(rule.type, CSSRule.PAGE_RULE, "Should be a page rule");
+  assert_equals(rule.style.length, 1, "Transform doesn't quite apply to pages");
+  assert_equals(rule.style.marginTop, "10px", "Should have a margin-top declaration");
+  rule.style.setProperty("transform", "scale(1)");
+  assert_equals(rule.style.getPropertyValue("transform"), "", "Shouldn't have been able to set the transform property via setProperty");
+  assert_equals(rule.style.length, 1, "Shouldn't have been able to set transform via setProperty");
+  rule.style.cssText = "margin-bottom: 10px; transform: scale(1);";
+  assert_equals(rule.style.length, 1, "Should not have been able to set transform via cssText");
+  assert_equals(rule.style.marginBottom, "10px", "Should have a margin-bottom declaration");
+}, "@page");
+
+test(function() {
+  let rule = document.styleSheets[0].cssRules[1].cssRules[0];
+  assert_equals(rule.type, CSSRule.KEYFRAME_RULE, "Should be a keyframe rule");
+  assert_equals(rule.style.length, 1, "animation-name doesn't apply to keyframes");
+  assert_equals(rule.style.marginTop, "10px", "Should have a margin-top declaration");
+  rule.style.setProperty("animation-name", "none");
+  assert_equals(rule.style.getPropertyValue("animation-name"), "", "Shouldn't have been able to set the animation-nameproperty via setProperty");
+  assert_equals(rule.style.length, 1, "Shouldn't have been able to set animation-name via setProperty");
+  rule.style.cssText = "margin-bottom: 10px; animation-name: none;";
+  assert_equals(rule.style.length, 1, "Should not have been able to set animation-name via cssText");
+  assert_equals(rule.style.marginBottom, "10px", "Should have a margin-bottom declaration");
+
+}, "@keyframe");
+</script>