Added initial configuration for BSAN.

Specified bsan branch of LLVM submodule.

Added Borrow sanitizer options to frontend.

Added additional configuration flags for BSAN.

Updated llvm submodule and ensured that retags are allowed in subsequent MIR passes.

Updated LLVM project.

Author: icmccorm

.github/workflows/sync.yml

@@ -0,0 +1,27 @@
+name: sync
+on: workflow_dispatch
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+defaults:
+  run:
+    shell: bash
+concurrency:
+  group: "sync"
+  cancel-in-progress: true
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Identity
+        run: |
+          git config --global user.name "github-actions[bot]"
+          git config --global user.email "github-actions[bot]@users.noreply.github.com"
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: Rebase
+        run: src/ci/scripts/sync.sh
+      - name: Build
+        run: ./x.py build --stage 1 library

.gitmodules

@@ -50,4 +50,4 @@
 [submodule "src/gcc"]
 	path = src/gcc
 	url = https://github.com/rust-lang/gcc.git
-	shallow = true
+	shallow = true

Cargo.lock

@@ -334,6 +334,10 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "bsan"
+version = "0.1.0"
+
 [[package]]
 name = "bstr"
 version = "1.12.0"

Cargo.toml

@@ -11,6 +11,7 @@ members = [
   "src/rustdoc-json-types",
   "src/tools/build-manifest",
   "src/tools/bump-stage0",
+  "src/tools/bsan",
   "src/tools/cargotest",
   "src/tools/clippy",
   "src/tools/clippy/clippy_dev",

compiler/rustc_borrowck/src/lib.rs

@@ -772,8 +772,12 @@ impl<'a, 'tcx> ResultsVisitor<'tcx, Borrowck<'a, 'tcx>> for MirBorrowckCtxt<'a,
                     state,
                 );
             }
+            StatementKind::Retag { .. } => {
+                if !self.infcx.tcx.sess.emit_retags() {
+                    bug!("Statement not allowed in this MIR phase")
+                }
+            }
             StatementKind::Nop
-            | StatementKind::Retag { .. }
             | StatementKind::Deinit(..)
             | StatementKind::SetDiscriminant { .. } => {
                 bug!("Statement not allowed in this MIR phase")
@@ -1973,11 +1977,11 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, '_, 'tcx> {
                 mpi,
             );
         } // Only query longest prefix with a MovePath, not further
-        // ancestors; dataflow recurs on children when parents
-        // move (to support partial (re)inits).
-        //
-        // (I.e., querying parents breaks scenario 7; but may want
-        // to do such a query based on partial-init feature-gate.)
+          // ancestors; dataflow recurs on children when parents
+          // move (to support partial (re)inits).
+          //
+          // (I.e., querying parents breaks scenario 7; but may want
+          // to do such a query based on partial-init feature-gate.)
     }
 
     /// Subslices correspond to multiple move paths, so we iterate through the

compiler/rustc_codegen_llvm/src/attributes.rs

@@ -131,6 +131,9 @@ pub(crate) fn sanitize_attrs<'ll>(
     if enabled.contains(SanitizerSet::SAFESTACK) {
         attrs.push(llvm::AttributeKind::SanitizeSafeStack.create_attr(cx.llcx));
     }
+    if enabled.contains(SanitizerSet::BORROW) {
+        attrs.push(llvm::AttributeKind::SanitizeBorrow.create_attr(cx.llcx));
+    }
     attrs
 }
 

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -644,6 +644,7 @@ pub(crate) unsafe fn llvm_optimize(
             sanitize_kernel_address_recover: config
                 .sanitizer_recover
                 .contains(SanitizerSet::KERNELADDRESS),
+            sanitize_borrow: config.sanitizer.contains(SanitizerSet::BORROW),
         })
     } else {
         None

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -238,6 +238,7 @@ pub(crate) enum AttributeKind {
     FnRetThunkExtern = 41,
     Writable = 42,
     DeadOnUnwind = 43,
+    SanitizeBorrow = 44,
 }
 
 /// LLVMIntPredicate
@@ -529,6 +530,7 @@ pub(crate) struct SanitizerOptions {
     pub sanitize_hwaddress_recover: bool,
     pub sanitize_kernel_address: bool,
     pub sanitize_kernel_address_recover: bool,
+    pub sanitize_borrow: bool,
 }
 
 /// LLVMRustRelocModel

compiler/rustc_codegen_llvm/src/retag.rs

@@ -1225,6 +1225,9 @@ fn add_sanitizer_libraries(
     if sanitizer.contains(SanitizerSet::ADDRESS) {
         link_sanitizer_runtime(sess, flavor, linker, "asan");
     }
+    if sanitizer.contains(SanitizerSet::BORROW) {
+        link_sanitizer_runtime(sess, flavor, linker, "bsan");
+    }
     if sanitizer.contains(SanitizerSet::DATAFLOW) {
         link_sanitizer_runtime(sess, flavor, linker, "dfsan");
     }