Remove the no_sanitize attribute in favor of sanitize

This removes the #[no_sanitize] attribute, which was behind an unstable
feature named no_sanitize. Instead, we introduce the sanitize attribute
which is more powerful and allows to be extended in the future (instead
of just focusing on turning sanitizers off).

This also makes sanitize(kernel_address = ..) attribute work with
-Zsanitize=address

To do it the same as how clang disables address sanitizer, we now
disable ASAN on sanitize(kernel_address = "off") and KASAN on
sanitize(address = "off").

The same was added to clang in https://reviews.llvm.org/D44981.

Author: 1c3t3a

compiler/rustc_codegen_ssa/messages.ftl

@@ -171,11 +171,8 @@ codegen_ssa_invalid_monomorphization_unsupported_symbol = invalid monomorphizati
 
 codegen_ssa_invalid_monomorphization_unsupported_symbol_of_size = invalid monomorphization of `{$name}` intrinsic: unsupported {$symbol} from `{$in_ty}` with element `{$in_elem}` of size `{$size}` to `{$ret_ty}`
 
-codegen_ssa_invalid_no_sanitize = invalid argument for `no_sanitize`
-    .note = expected one of: `address`, `cfi`, `hwaddress`, `kcfi`, `memory`, `memtag`, `shadow-call-stack`, or `thread`
-
 codegen_ssa_invalid_sanitize = invalid argument for `sanitize`
-    .note = expected one of: `address`, `cfi`, `hwaddress`, `kcfi`, `memory`, `memtag`, `shadow-call-stack`, or `thread`
+    .note = expected one of: `address`, `kernel_address`, `cfi`, `hwaddress`, `kcfi`, `memory`, `memtag`, `shadow_call_stack`, or `thread`
 
 codegen_ssa_invalid_windows_subsystem = invalid windows subsystem `{$subsystem}`, only `windows` and `console` are allowed
 

compiler/rustc_codegen_ssa/src/codegen_attrs.rs

@@ -77,32 +77,6 @@ fn parse_instruction_set_attr(tcx: TyCtxt<'_>, attr: &Attribute) -> Option<Instr
     }
 }
 
-// FIXME(jdonszelmann): remove when no_sanitize becomes a parsed attr
-fn parse_no_sanitize_attr(tcx: TyCtxt<'_>, attr: &Attribute) -> Option<SanitizerSet> {
-    let list = attr.meta_item_list()?;
-    let mut sanitizer_set = SanitizerSet::empty();
-
-    for item in list.iter() {
-        match item.name() {
-            Some(sym::address) => {
-                sanitizer_set |= SanitizerSet::ADDRESS | SanitizerSet::KERNELADDRESS
-            }
-            Some(sym::cfi) => sanitizer_set |= SanitizerSet::CFI,
-            Some(sym::kcfi) => sanitizer_set |= SanitizerSet::KCFI,
-            Some(sym::memory) => sanitizer_set |= SanitizerSet::MEMORY,
-            Some(sym::memtag) => sanitizer_set |= SanitizerSet::MEMTAG,
-            Some(sym::shadow_call_stack) => sanitizer_set |= SanitizerSet::SHADOWCALLSTACK,
-            Some(sym::thread) => sanitizer_set |= SanitizerSet::THREAD,
-            Some(sym::hwaddress) => sanitizer_set |= SanitizerSet::HWADDRESS,
-            _ => {
-                tcx.dcx().emit_err(errors::InvalidNoSanitize { span: item.span() });
-            }
-        }
-    }
-
-    Some(sanitizer_set)
-}
-
 // FIXME(jdonszelmann): remove when patchable_function_entry becomes a parsed attr
 fn parse_patchable_function_entry(
     tcx: TyCtxt<'_>,
@@ -161,7 +135,6 @@ fn parse_patchable_function_entry(
 #[derive(Default)]
 struct InterestingAttributeDiagnosticSpans {
     link_ordinal: Option<Span>,
-    no_sanitize: Option<Span>,
     sanitize: Option<Span>,
     inline: Option<Span>,
     no_mangle: Option<Span>,
@@ -339,11 +312,6 @@ fn process_builtin_attrs(
                 codegen_fn_attrs.flags |= CodegenFnAttrFlags::ALLOCATOR_ZEROED
             }
             sym::thread_local => codegen_fn_attrs.flags |= CodegenFnAttrFlags::THREAD_LOCAL,
-            sym::no_sanitize => {
-                interesting_spans.no_sanitize = Some(attr.span());
-                codegen_fn_attrs.no_sanitize |=
-                    parse_no_sanitize_attr(tcx, attr).unwrap_or_default();
-            }
             sym::sanitize => interesting_spans.sanitize = Some(attr.span()),
             sym::instruction_set => {
                 codegen_fn_attrs.instruction_set = parse_instruction_set_attr(tcx, attr)
@@ -467,24 +435,14 @@ fn check_result(
     if !codegen_fn_attrs.no_sanitize.is_empty()
         && codegen_fn_attrs.inline.always()
         && let (Some(no_sanitize_span), Some(inline_span)) =
-            (interesting_spans.no_sanitize, interesting_spans.inline)
+            (interesting_spans.sanitize, interesting_spans.inline)
     {
         let hir_id = tcx.local_def_id_to_hir_id(did);
         tcx.node_span_lint(lint::builtin::INLINE_NO_SANITIZE, hir_id, no_sanitize_span, |lint| {
             lint.primary_message("`no_sanitize` will have no effect after inlining");
             lint.span_note(inline_span, "inlining requested here");
         })
     }
-    if !codegen_fn_attrs.no_sanitize.is_empty()
-        && codegen_fn_attrs.inline.always()
-        && let (Some(sanitize_span), Some(inline_span)) = (interesting_spans.sanitize, interesting_spans.inline)
-    {
-        let hir_id = tcx.local_def_id_to_hir_id(did);
-        tcx.node_span_lint(lint::builtin::INLINE_NO_SANITIZE, hir_id, sanitize_span, |lint| {
-            lint.primary_message("setting `sanitize` off will have no effect after inlining");
-            lint.span_note(inline_span, "inlining requested here");
-        })
-    }
 
     // error when specifying link_name together with link_ordinal
     if let Some(_) = codegen_fn_attrs.link_name
@@ -608,9 +566,14 @@ fn opt_trait_item(tcx: TyCtxt<'_>, def_id: DefId) -> Option<DefId> {
 }
 
 /// For an attr that has the `sanitize` attribute, read the list of
-/// disabled sanitizers.
-fn parse_sanitize_attr(tcx: TyCtxt<'_>, attr: &Attribute) -> SanitizerSet {
-    let mut result = SanitizerSet::empty();
+/// disabled sanitizers. `current_attr` holds the information about
+/// previously parsed attributes.
+fn parse_sanitize_attr(
+    tcx: TyCtxt<'_>,
+    attr: &Attribute,
+    current_attr: SanitizerSet,
+) -> SanitizerSet {
+    let mut result = current_attr;
     if let Some(list) = attr.meta_item_list() {
         for item in list.iter() {
             let MetaItemInner::MetaItem(set) = item else {
@@ -619,10 +582,13 @@ fn parse_sanitize_attr(tcx: TyCtxt<'_>, attr: &Attribute) -> SanitizerSet {
             };
             let segments = set.path.segments.iter().map(|x| x.ident.name).collect::<Vec<_>>();
             match segments.as_slice() {
-                [sym::address] if set.value_str() == Some(sym::off) => {
+                // Similar to clang, sanitize(address = ..) and
+                // sanitize(kernel_address = ..) control both ASan and KASan
+                // Source: https://reviews.llvm.org/D44981.
+                [sym::address] | [sym::kernel_address] if set.value_str() == Some(sym::off) => {
                     result |= SanitizerSet::ADDRESS | SanitizerSet::KERNELADDRESS
                 }
-                [sym::address] if set.value_str() == Some(sym::on) => {
+                [sym::address] | [sym::kernel_address] if set.value_str() == Some(sym::on) => {
                     result &= !SanitizerSet::ADDRESS;
                     result &= !SanitizerSet::KERNELADDRESS;
                 }
@@ -670,19 +636,20 @@ fn parse_sanitize_attr(tcx: TyCtxt<'_>, attr: &Attribute) -> SanitizerSet {
 }
 
 fn disabled_sanitizers_for(tcx: TyCtxt<'_>, did: LocalDefId) -> SanitizerSet {
-    // Check for a sanitize annotation directly on this def.
-    if let Some(attr) = tcx.get_attr(did, sym::sanitize) {
-        return parse_sanitize_attr(tcx, attr);
-    }
-
-    // Otherwise backtrack.
-    match tcx.opt_local_parent(did) {
+    // Backtrack to the crate root.
+    let disabled = match tcx.opt_local_parent(did) {
         // Check the parent (recursively).
         Some(parent) => tcx.disabled_sanitizers_for(parent),
         // We reached the crate root without seeing an attribute, so
         // there is no sanitizers to exclude.
         None => SanitizerSet::empty(),
+    };
+
+    // Check for a sanitize annotation directly on this def.
+    if let Some(attr) = tcx.get_attr(did, sym::sanitize) {
+        return parse_sanitize_attr(tcx, attr, disabled);
     }
+    disabled
 }
 
 /// Checks if the provided DefId is a method in a trait impl for a trait which has track_caller

compiler/rustc_codegen_ssa/src/errors.rs

@@ -1120,14 +1120,6 @@ impl IntoDiagArg for ExpectedPointerMutability {
     }
 }
 
-#[derive(Diagnostic)]
-#[diag(codegen_ssa_invalid_no_sanitize)]
-#[note]
-pub(crate) struct InvalidNoSanitize {
-    #[primary_span]
-    pub span: Span,
-}
-
 #[derive(Diagnostic)]
 #[diag(codegen_ssa_invalid_sanitize)]
 #[note]

compiler/rustc_feature/src/builtin_attrs.rs

@@ -741,12 +741,7 @@ pub static BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
         ErrorPreceding, EncodeCrossCrate::No
     ),
     gated!(
-        no_sanitize, Normal,
-        template!(List: &["address, kcfi, memory, thread"]), DuplicatesOk,
-        EncodeCrossCrate::No, experimental!(no_sanitize)
-    ),
-    gated!(
-        sanitize, Normal, template!(List: r#"address = "on|off", cfi = "on|off""#), ErrorPreceding,
+        sanitize, Normal, template!(List: &[r#"address = "on|off""#, r#"kernel_address = "on|off""#, r#"cfi = "on|off""#, r#"hwaddress = "on|off""#, r#"kcfi = "on|off""#, r#"memory = "on|off""#, r#"memtag = "on|off""#, r#"shadow_call_stack = "on|off""#, r#"thread = "on|off""#]), ErrorPreceding,
         EncodeCrossCrate::No, sanitize, experimental!(sanitize),
     ),
     gated!(

compiler/rustc_feature/src/removed.rs

@@ -190,6 +190,9 @@ declare_features! (
     (removed, no_coverage, "1.74.0", Some(84605), Some("renamed to `coverage_attribute`"), 114656),
     /// Allows `#[no_debug]`.
     (removed, no_debug, "1.43.0", Some(29721), Some("removed due to lack of demand"), 69667),
+    // Allows the use of `no_sanitize` attribute.
+    /// The feature was renamed to `sanitize` and the attribute to `#[sanitize(xyz = "on|off")]`
+    (removed, no_sanitize, "CURRENT_RUSTC_VERSION", Some(39699), Some(r#"renamed to sanitize(xyz = "on|off")"#), 142681),
     /// Note: this feature was previously recorded in a separate
     /// `STABLE_REMOVED` list because it, uniquely, was once stable but was
     /// then removed. But there was no utility storing it separately, so now

compiler/rustc_feature/src/unstable.rs

@@ -592,8 +592,6 @@ declare_features! (
     (unstable, new_range, "1.86.0", Some(123741)),
     /// Allows `#![no_core]`.
     (unstable, no_core, "1.3.0", Some(29639)),
-    /// Allows the use of `no_sanitize` attribute.
-    (unstable, no_sanitize, "1.42.0", Some(39699)),
     /// Allows using the `non_exhaustive_omitted_patterns` lint.
     (unstable, non_exhaustive_omitted_patterns_lint, "1.57.0", Some(89554)),
     /// Allows `for<T>` binders in where-clauses

compiler/rustc_lint_defs/src/builtin.rs

@@ -2301,18 +2301,18 @@ declare_lint! {
 
 declare_lint! {
     /// The `inline_no_sanitize` lint detects incompatible use of
-    /// [`#[inline(always)]`][inline] and [`#[no_sanitize(...)]`][no_sanitize].
+    /// [`#[inline(always)]`][inline] and [`#[sanitize(xyz = "off")]`][sanitize].
     ///
     /// [inline]: https://doc.rust-lang.org/reference/attributes/codegen.html#the-inline-attribute
-    /// [no_sanitize]: https://doc.rust-lang.org/nightly/unstable-book/language-features/no-sanitize.html
+    /// [sanitize]: https://doc.rust-lang.org/nightly/unstable-book/language-features/no-sanitize.html
     ///
     /// ### Example
     ///
     /// ```rust
-    /// #![feature(no_sanitize)]
+    /// #![feature(sanitize)]
     ///
     /// #[inline(always)]
-    /// #[no_sanitize(address)]
+    /// #[sanitize(address = "off")]
     /// fn x() {}
     ///
     /// fn main() {
@@ -2325,11 +2325,11 @@ declare_lint! {
     /// ### Explanation
     ///
     /// The use of the [`#[inline(always)]`][inline] attribute prevents the
-    /// the [`#[no_sanitize(...)]`][no_sanitize] attribute from working.
+    /// the [`#[sanitize(xyz = "off")]`][sanitize] attribute from working.
     /// Consider temporarily removing `inline` attribute.
     pub INLINE_NO_SANITIZE,
     Warn,
-    "detects incompatible use of `#[inline(always)]` and `#[no_sanitize(...)]`",
+    r#"detects incompatible use of `#[inline(always)]` and `#[sanitize(... = "off")]`"#,
 }
 
 declare_lint! {

compiler/rustc_middle/src/middle/codegen_fn_attrs.rs

@@ -62,8 +62,8 @@ pub struct CodegenFnAttrs {
     /// The `#[link_section = "..."]` attribute, or what executable section this
     /// should be placed in.
     pub link_section: Option<Symbol>,
-    /// The `#[no_sanitize(...)]` attribute. Indicates sanitizers for which
-    /// instrumentation should be disabled inside the annotated function.
+    /// The `#[sanitize(xyz = "off")]` attribute. Indicates sanitizers for which
+    /// instrumentation should be disabled inside the function.
     pub no_sanitize: SanitizerSet,
     /// The `#[instruction_set(set)]` attribute. Indicates if the generated code should
     /// be generated against a specific instruction set. Only usable on architectures which allow

compiler/rustc_passes/messages.ftl

@@ -542,10 +542,6 @@ passes_no_mangle_foreign =
     .note = symbol names in extern blocks are not mangled
     .suggestion = remove this attribute
 
-passes_no_sanitize =
-    `#[no_sanitize({$attr_str})]` should be applied to {$accepted_kind}
-    .label = not {$accepted_kind}
-
 passes_non_exhaustive_with_default_field_values =
     `#[non_exhaustive]` can't be used to annotate items with default field values
     .label = this struct has default field values

compiler/rustc_passes/src/check_attr.rs

@@ -344,9 +344,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                         [sym::diagnostic, sym::on_unimplemented, ..] => {
                             self.check_diagnostic_on_unimplemented(attr.span(), hir_id, target)
                         }
-                        [sym::no_sanitize, ..] => {
-                            self.check_no_sanitize(attr, span, target)
-                        }
                         [sym::sanitize, ..] => {
                             self.check_sanitize(attr, span, target)
                         }
@@ -664,42 +661,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
         }
     }
 
-    fn check_no_sanitize(&self, attr: &Attribute, span: Span, target: Target) {
-        if let Some(list) = attr.meta_item_list() {
-            for item in list.iter() {
-                let sym = item.name();
-                match sym {
-                    Some(s @ sym::address | s @ sym::hwaddress) => {
-                        let is_valid =
-                            matches!(target, Target::Fn | Target::Method(..) | Target::Static);
-                        if !is_valid {
-                            self.dcx().emit_err(errors::NoSanitize {
-                                attr_span: item.span(),
-                                defn_span: span,
-                                accepted_kind: "a function or static",
-                                attr_str: s.as_str(),
-                            });
-                        }
-                    }
-                    _ => {
-                        let is_valid = matches!(target, Target::Fn | Target::Method(..));
-                        if !is_valid {
-                            self.dcx().emit_err(errors::NoSanitize {
-                                attr_span: item.span(),
-                                defn_span: span,
-                                accepted_kind: "a function",
-                                attr_str: &match sym {
-                                    Some(name) => name.to_string(),
-                                    None => "...".to_string(),
-                                },
-                            });
-                        }
-                    }
-                }
-            }
-        }
-    }
-
     /// Checks that the `#[sanitize(..)]` attribute is applied to a
     /// function/closure/method, or to an impl block or module.
     fn check_sanitize(&self, attr: &Attribute, target_span: Span, target: Target) {