add option to track all read/write accesses to tracked allocations

Author: RalfJung

src/bin/miri.rs

@@ -534,6 +534,8 @@ fn main() {
                     ),
             };
             miri_config.tracked_alloc_ids.extend(ids);
+        } else if arg == "-Zmiri-track-alloc-accesses" {
+            miri_config.track_alloc_accesses = true;
         } else if let Some(param) = arg.strip_prefix("-Zmiri-compare-exchange-weak-failure-rate=") {
             let rate = match param.parse::<f64>() {
                 Ok(rate) if rate >= 0.0 && rate <= 1.0 => rate,

src/borrow_tracker/mod.rs

@@ -122,13 +122,6 @@ impl VisitProvenance for GlobalStateInner {
 /// We need interior mutable access to the global state.
 pub type GlobalState = RefCell<GlobalStateInner>;
 
-/// Indicates which kind of access is being performed.
-#[derive(Copy, Clone, Hash, PartialEq, Eq, Debug)]
-pub enum AccessKind {
-    Read,
-    Write,
-}
-
 impl fmt::Display for AccessKind {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {

src/borrow_tracker/stacked_borrows/diagnostics.rs

@@ -5,7 +5,7 @@ use rustc_data_structures::fx::FxHashSet;
 use rustc_span::{Span, SpanData};
 use rustc_target::abi::Size;
 
-use crate::borrow_tracker::{AccessKind, GlobalStateInner, ProtectorKind};
+use crate::borrow_tracker::{GlobalStateInner, ProtectorKind};
 use crate::*;
 
 /// Error reporting

src/borrow_tracker/stacked_borrows/mod.rs

@@ -16,7 +16,7 @@ use rustc_target::abi::{Abi, Size};
 
 use crate::borrow_tracker::{
     stacked_borrows::diagnostics::{AllocHistory, DiagnosticCx, DiagnosticCxBuilder},
-    AccessKind, GlobalStateInner, ProtectorKind,
+    GlobalStateInner, ProtectorKind,
 };
 use crate::*;
 

src/borrow_tracker/tree_borrows/diagnostics.rs

@@ -9,7 +9,7 @@ use crate::borrow_tracker::tree_borrows::{
     tree::LocationState,
     unimap::UniIndex,
 };
-use crate::borrow_tracker::{AccessKind, ProtectorKind};
+use crate::borrow_tracker::ProtectorKind;
 use crate::*;
 
 /// Cause of an access: either a real access or one

src/borrow_tracker/tree_borrows/mod.rs

@@ -1,6 +1,6 @@
 use rustc_target::abi::{Abi, Size};
 
-use crate::borrow_tracker::{AccessKind, GlobalState, GlobalStateInner, ProtectorKind};
+use crate::borrow_tracker::{GlobalState, GlobalStateInner, ProtectorKind};
 use rustc_middle::{
     mir::{Mutability, RetagKind},
     ty::{

src/borrow_tracker/tree_borrows/perms.rs

@@ -3,7 +3,7 @@ use std::fmt;
 
 use crate::borrow_tracker::tree_borrows::diagnostics::TransitionError;
 use crate::borrow_tracker::tree_borrows::tree::AccessRelatedness;
-use crate::borrow_tracker::AccessKind;
+use crate::AccessKind;
 
 /// The activation states of a pointer.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]

src/borrow_tracker/tree_borrows/tree.rs

@@ -24,7 +24,7 @@ use crate::borrow_tracker::tree_borrows::{
     unimap::{UniEntry, UniIndex, UniKeyMap, UniValMap},
     Permission,
 };
-use crate::borrow_tracker::{AccessKind, GlobalState, ProtectorKind};
+use crate::borrow_tracker::{GlobalState, ProtectorKind};
 use crate::*;
 
 mod tests;

src/diagnostics.rs

@@ -116,6 +116,7 @@ pub enum NonHaltingDiagnostic {
     CreatedCallId(CallId),
     CreatedAlloc(AllocId, Size, Align, MemoryKind<MiriMemoryKind>),
     FreedAlloc(AllocId),
+    AccessedAlloc(AllocId, AccessKind),
     RejectedIsolatedOp(String),
     ProgressReport {
         block_count: u64, // how many basic blocks have been run so far
@@ -538,6 +539,7 @@ impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> {
             | PoppedPointerTag(..)
             | CreatedCallId(..)
             | CreatedAlloc(..)
+            | AccessedAlloc(..)
             | FreedAlloc(..)
             | ProgressReport { .. }
             | WeakMemoryOutdatedLoad => ("tracking was triggered".to_string(), DiagLevel::Note),
@@ -559,6 +561,8 @@ impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> {
                     size = size.bytes(),
                     align = align.bytes(),
                 ),
+            AccessedAlloc(AllocId(id), access_kind) =>
+                format!("{access_kind} access to allocation with id {id}"),
             FreedAlloc(AllocId(id)) => format!("freed allocation with id {id}"),
             RejectedIsolatedOp(ref op) =>
                 format!("{op} was made to return an error due to isolation"),

src/eval.rs

@@ -112,6 +112,8 @@ pub struct MiriConfig {
     pub tracked_call_ids: FxHashSet<CallId>,
     /// The allocation ids to report about.
     pub tracked_alloc_ids: FxHashSet<AllocId>,
+    /// For the tracked alloc ids, also report read/write accesses.
+    pub track_alloc_accesses: bool,
     /// Determine if data race detection should be enabled
     pub data_race_detector: bool,
     /// Determine if weak memory emulation should be enabled. Requires data race detection to be enabled
@@ -169,6 +171,7 @@ impl Default for MiriConfig {
             tracked_pointer_tags: FxHashSet::default(),
             tracked_call_ids: FxHashSet::default(),
             tracked_alloc_ids: FxHashSet::default(),
+            track_alloc_accesses: false,
             data_race_detector: true,
             weak_memory_emulation: true,
             track_outdated_loads: false,

src/helpers.rs

@@ -22,6 +22,13 @@ use rand::RngCore;
 
 use crate::*;
 
+/// Indicates which kind of access is being performed.
+#[derive(Copy, Clone, Hash, PartialEq, Eq, Debug)]
+pub enum AccessKind {
+    Read,
+    Write,
+}
+
 // This mapping should match `decode_error_kind` in
 // <https://github.com/rust-lang/rust/blob/master/library/std/src/sys/pal/unix/mod.rs>.
 const UNIX_IO_ERROR_TABLE: &[(&str, std::io::ErrorKind)] = {

src/lib.rs

@@ -120,7 +120,7 @@ pub use crate::diagnostics::{
 pub use crate::eval::{
     create_ecx, eval_entry, AlignmentCheck, BacktraceStyle, IsolatedOp, MiriConfig, RejectOpWith,
 };
-pub use crate::helpers::EvalContextExt as _;
+pub use crate::helpers::{AccessKind, EvalContextExt as _};
 pub use crate::intptrcast::{EvalContextExt as _, ProvenanceMode};
 pub use crate::machine::{
     AllocExtra, FrameExtra, MiriInterpCx, MiriInterpCxExt, MiriMachine, MiriMemoryKind,

src/machine.rs

@@ -512,6 +512,8 @@ pub struct MiriMachine<'mir, 'tcx> {
     /// The allocation IDs to report when they are being allocated
     /// (helps for debugging memory leaks and use after free bugs).
     tracked_alloc_ids: FxHashSet<AllocId>,
+    /// For the tracked alloc ids, also report read/write accesses.
+    track_alloc_accesses: bool,
 
     /// Controls whether alignment of memory accesses is being checked.
     pub(crate) check_alignment: AlignmentCheck,
@@ -654,6 +656,7 @@ impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> {
             extern_statics: FxHashMap::default(),
             rng: RefCell::new(rng),
             tracked_alloc_ids: config.tracked_alloc_ids.clone(),
+            track_alloc_accesses: config.track_alloc_accesses,
             check_alignment: config.check_alignment,
             cmpxchg_weak_failure_rate: config.cmpxchg_weak_failure_rate,
             mute_stdout_stderr: config.mute_stdout_stderr,
@@ -793,6 +796,7 @@ impl VisitProvenance for MiriMachine<'_, '_> {
             local_crates: _,
             rng: _,
             tracked_alloc_ids: _,
+            track_alloc_accesses: _,
             check_alignment: _,
             cmpxchg_weak_failure_rate: _,
             mute_stdout_stderr: _,
@@ -1235,6 +1239,10 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for MiriMachine<'mir, 'tcx> {
         (alloc_id, prov_extra): (AllocId, Self::ProvenanceExtra),
         range: AllocRange,
     ) -> InterpResult<'tcx> {
+        if machine.track_alloc_accesses && machine.tracked_alloc_ids.contains(&alloc_id) {
+            machine
+                .emit_diagnostic(NonHaltingDiagnostic::AccessedAlloc(alloc_id, AccessKind::Read));
+        }
         if let Some(data_race) = &alloc_extra.data_race {
             data_race.read(alloc_id, range, machine)?;
         }
@@ -1255,6 +1263,10 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for MiriMachine<'mir, 'tcx> {
         (alloc_id, prov_extra): (AllocId, Self::ProvenanceExtra),
         range: AllocRange,
     ) -> InterpResult<'tcx> {
+        if machine.track_alloc_accesses && machine.tracked_alloc_ids.contains(&alloc_id) {
+            machine
+                .emit_diagnostic(NonHaltingDiagnostic::AccessedAlloc(alloc_id, AccessKind::Write));
+        }
         if let Some(data_race) = &mut alloc_extra.data_race {
             data_race.write(alloc_id, range, machine)?;
         }