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Tree Borrows: improved diagnostics

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This commit is contained in:
Neven Villani 2023-03-29 22:17:33 +02:00 committed by Ralf Jung
parent db73863c42
commit fe178ccb72
21 changed files with 803 additions and 248 deletions
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240
src/tools/miri/src/borrow_tracker/tree_borrows/diagnostics.rs
View File

@ -1,14 +1,90 @@
use rustc_data_structures::fx::FxHashMap;
use std::fmt;
use std::ops::Range;
use rustc_data_structures::fx::FxHashMap;
use rustc_span::{Span, SpanData};
use rustc_target::abi::Size;
use crate::borrow_tracker::tree_borrows::{
err_tb_ub, perms::Permission, tree::LocationState, unimap::UniIndex,
perms::{PermTransition, Permission},
tree::LocationState,
unimap::UniIndex,
};
use crate::borrow_tracker::{AccessKind, ProtectorKind};
use crate::*;
/// Complete data for an event:
/// - `kind` is what happened to the permissions
/// - `access_kind` and `access_range` describe the access that caused the event
/// - `offset` allows filtering only the relevant events for a given memory location
/// (see how we perform the filtering in `History::extract_relevant`.
/// - `span` is the line of code in question
#[derive(Clone, Debug)]
pub struct Event {
pub transition: PermTransition,
pub access_kind: AccessKind,
pub is_foreign: bool,
pub access_range: AllocRange,
pub offset: Size,
pub span: Span,
}
/// List of all events that affected a tag.
/// NOTE: not all of these events are relevant for a particular location,
/// the events should be filtered before the generation of diagnostics.
/// Available filtering methods include `History::forget` and `History::extract_relevant`.
#[derive(Clone, Debug)]
pub struct History {
pub tag: BorTag,
pub created: (Span, Permission),
pub events: Vec<Event>,
}
/// History formatted for use by `src/diagnostics.rs`.
///
/// NOTE: needs to be `Send` because of a bound on `MachineStopType`, hence
/// the use of `SpanData` rather than `Span`.
#[derive(Debug, Clone, Default)]
pub struct HistoryData {
pub events: Vec<(Option<SpanData>, String)>, // includes creation
}
impl History {
/// Record an additional event to the history.
pub fn push(&mut self, event: Event) {
self.events.push(event);
}
}
impl HistoryData {
// Format events from `new_history` into those recorded by `self`.
//
// NOTE: also converts `Span` to `SpanData`.
pub fn extend(
&mut self,
new_history: History,
tag_name: &'static str,
show_initial_state: bool,
) {
let History { tag, created, events } = new_history;
let this = format!("the {tag_name} tag {tag:?}");
let msg_initial_state = format!(", in the initial state {}", created.1);
let msg_creation = format!(
"{this} was created here{maybe_msg_initial_state}.",
maybe_msg_initial_state = if show_initial_state { &msg_initial_state } else { "" },
);
self.events.push((Some(created.0.data()), msg_creation));
for &Event { transition, access_kind, is_foreign, access_range, span, offset: _ } in &events
{
// NOTE: `offset` is explicitly absent from the error message, it has no significance
// to the user. The meaningful one is `access_range`.
self.events.push((Some(span.data()), format!("{this} then transitioned {transition} due to a {rel} {access_kind} at offsets {access_range:?}.", rel = if is_foreign { "foreign" } else { "child" })));
self.events.push((None, format!("this corresponds to {}.", transition.summary())));
}
}
}
/// Some information that is irrelevant for the algorithm but very
/// convenient to know about a tag for debugging and testing.
#[derive(Clone, Debug)]
@ -20,18 +96,29 @@ pub struct NodeDebugInfo {
/// pointer in the source code.
/// Helps match tag numbers to human-readable names.
pub name: Option<String>,
/// Notable events in the history of this tag, used for
/// diagnostics.
///
/// NOTE: by virtue of being part of `NodeDebugInfo`,
/// the history is automatically cleaned up by the GC.
/// NOTE: this is `!Send`, it needs to be converted before displaying
/// the actual diagnostics because `src/diagnostics.rs` requires `Send`.
pub history: History,
}
impl NodeDebugInfo {
/// New node info with a name.
pub fn new(tag: BorTag) -> Self {
Self { tag, name: None }
/// Information for a new node. By default it has no
/// name and an empty history.
pub fn new(tag: BorTag, initial: Permission, span: Span) -> Self {
let history = History { tag, created: (span, initial), events: Vec::new() };
Self { tag, name: None, history }
}
/// Add a name to the tag. If a same tag is associated to several pointers,
/// it can have several names which will be separated by commas.
fn add_name(&mut self, name: &str) {
pub fn add_name(&mut self, name: &str) {
if let Some(ref mut prev_name) = &mut self.name {
prev_name.push(',');
prev_name.push_str(", ");
prev_name.push_str(name);
} else {
self.name = Some(String::from(name));
@ -42,7 +129,7 @@ impl NodeDebugInfo {
impl fmt::Display for NodeDebugInfo {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
if let Some(ref name) = self.name {
write!(f, "{tag:?} (also named '{name}')", tag = self.tag)
write!(f, "{tag:?} ({name})", tag = self.tag)
} else {
write!(f, "{tag:?}", tag = self.tag)
}
@ -86,7 +173,7 @@ impl<'tcx> Tree {
}
}
#[derive(Debug, Clone, Copy)]
#[derive(Debug, Clone, Copy, PartialEq)]
pub(super) enum TransitionError {
/// This access is not allowed because some parent tag has insufficient permissions.
/// For example, if a tag is `Frozen` and encounters a child write this will
@ -96,63 +183,146 @@ pub(super) enum TransitionError {
/// A protector was triggered due to an invalid transition that loses
/// too much permissions.
/// For example, if a protected tag goes from `Active` to `Frozen` due
/// to a foreign write this will produce a `ProtectedTransition(Active, Frozen)`.
/// to a foreign write this will produce a `ProtectedTransition(PermTransition(Active, Frozen))`.
/// This kind of error can only occur on foreign accesses.
ProtectedTransition(Permission, Permission),
ProtectedTransition(PermTransition),
/// Cannot deallocate because some tag in the allocation is strongly protected.
/// This kind of error can only occur on deallocations.
ProtectedDealloc,
}
impl History {
/// Keep only the tag and creation
fn forget(&self) -> Self {
History { events: Vec::new(), created: self.created, tag: self.tag }
}
/// Reconstruct the history relevant to `error_offset` knowing that
/// its permission followed `complete_transition`.
///
/// Here's how we do this:
/// - we know `full := complete_transition` the transition of the permission from
/// its initialization to the state just before the error was caused,
/// we want to find a chain of events that produces `full`
/// - we decompose `full` into `pre o post` where
/// `pre` is the best applicable transition from recorded events
/// - we select the event that caused `pre` and iterate
/// to find the chain of events that produces `full := post`
///
/// To find the "best applicable transition" for full:
/// - eliminate events that cannot be applied because their offset is too big
/// - eliminate events that cannot be applied because their starting point is wrong
/// - select the one that happened closest to the range of interest
fn extract_relevant(&self, complete_transition: PermTransition, error_offset: Size) -> Self {
let mut selected_events: Vec<Event> = Vec::new();
let mut full = complete_transition;
while !full.is_noop() {
let (pre, post) = self
.events
.iter()
.filter(|e| e.offset <= error_offset)
.filter_map(|pre_canditate| {
full.apply_start(pre_canditate.transition)
.map(|post_canditate| (pre_canditate, post_canditate))
})
.max_by_key(|(pre_canditate, _post_candidate)| pre_canditate.offset)
.unwrap();
// If this occurs we will loop infinitely !
// Make sure to only put non-noop transitions in `History`.
assert!(!pre.transition.is_noop());
full = post;
selected_events.push(pre.clone());
}
History { events: selected_events, created: self.created, tag: self.tag }
}
}
/// Failures that can occur during the execution of Tree Borrows procedures.
pub(super) struct TbError<'node> {
/// What failure occurred.
pub error_kind: TransitionError,
/// The byte at which the conflict occured.
pub error_offset: Size,
/// The tag on which the error was triggered.
/// On protector violations, this is the tag that was protected.
/// On accesses rejected due to insufficient permissions, this is the
/// tag that lacked those permissions.
pub faulty_tag: &'node NodeDebugInfo,
pub conflicting_info: &'node NodeDebugInfo,
/// Whether this was a Read or Write access. This field is ignored
/// when the error was triggered by a deallocation.
pub access_kind: AccessKind,
/// Which tag the access that caused this error was made through, i.e.
/// which tag was used to read/write/deallocate.
pub tag_of_access: &'node NodeDebugInfo,
pub accessed_info: &'node NodeDebugInfo,
}
impl TbError<'_> {
/// Produce a UB error.
pub fn build<'tcx>(self) -> InterpErrorInfo<'tcx> {
pub fn build<'tcx>(self) -> InterpError<'tcx> {
use TransitionError::*;
err_tb_ub(match self.error_kind {
let started_as = self.conflicting_info.history.created.1;
let kind = self.access_kind;
let accessed = self.accessed_info;
let conflicting = self.conflicting_info;
let accessed_is_conflicting = accessed.tag == conflicting.tag;
let (pre_error, title, relation, problem, conflicting_tag_name) = match self.error_kind {
ChildAccessForbidden(perm) => {
format!(
"{kind} through {initial} is forbidden because it is a child of {current} which is {perm}.",
kind=self.access_kind,
initial=self.tag_of_access,
current=self.faulty_tag,
perm=perm,
let conflicting_tag_name =
if accessed_is_conflicting { "accessed" } else { "conflicting" };
(
perm,
format!("{kind} through {accessed} is forbidden."),
(!accessed_is_conflicting).then_some(format!(
"the accessed tag {accessed} is a child of the conflicting tag {conflicting}."
)),
format!(
"the {conflicting_tag_name} tag {conflicting} has state {perm} which forbids child {kind}es."
),
conflicting_tag_name,
)
}
ProtectedTransition(start, end) => {
format!(
"{kind} through {initial} is forbidden because it is a foreign tag for {current}, which would hence change from {start} to {end}, but {current} is protected",
current=self.faulty_tag,
start=start,
end=end,
kind=self.access_kind,
initial=self.tag_of_access,
ProtectedTransition(transition) => {
let conflicting_tag_name = "protected";
(
transition.started(),
format!("{kind} through {accessed} is forbidden."),
Some(format!(
"the accessed tag {accessed} is a foreign tag for the {conflicting_tag_name} tag {conflicting}."
)),
format!(
"the access would cause the {conflicting_tag_name} tag {conflicting} to transition {transition}. This is {loss}, which is not allowed for protected tags.",
loss = transition.summary(),
),
conflicting_tag_name,
)
}
ProtectedDealloc => {
format!(
"the allocation of {initial} also contains {current} which is strongly protected, cannot deallocate",
initial=self.tag_of_access,
current=self.faulty_tag,
let conflicting_tag_name = "strongly protected";
(
started_as,
format!("deallocation through {accessed} is forbidden."),
Some(format!(
"the allocation of the accessed tag {accessed} also contains the {conflicting_tag_name} tag {conflicting}."
)),
format!(
"the {conflicting_tag_name} tag {conflicting} disallows deallocations."
),
conflicting_tag_name,
)
}
}).into()
};
let pre_transition = PermTransition::from(started_as, pre_error).unwrap();
let mut history = HistoryData::default();
if !accessed_is_conflicting {
history.extend(self.accessed_info.history.forget(), "accessed", false);
}
history.extend(
self.conflicting_info.history.extract_relevant(pre_transition, self.error_offset),
conflicting_tag_name,
true,
);
err_machine_stop!(TerminationInfo::TreeBorrowsUb { title, relation, problem, history })
}
}

21
src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs
View File

@ -14,7 +14,7 @@ use rustc_middle::{
use crate::*;
mod diagnostics;
pub mod diagnostics;
mod perms;
mod tree;
mod unimap;
@ -23,10 +23,6 @@ pub use tree::Tree;
pub type AllocState = Tree;
pub fn err_tb_ub<'tcx>(msg: String) -> InterpError<'tcx> {
err_machine_stop!(TerminationInfo::TreeBorrowsUb { msg })
}
impl<'tcx> Tree {
/// Create a new allocation, i.e. a new tree
pub fn new_allocation(
@ -37,7 +33,8 @@ impl<'tcx> Tree {
machine: &MiriMachine<'_, 'tcx>,
) -> Self {
let tag = state.base_ptr_tag(id, machine); // Fresh tag for the root
Tree::new(tag, size)
let span = machine.current_span();
Tree::new(tag, size, span)
}
/// Check that an access on the entire range is permitted, and update
@ -64,7 +61,8 @@ impl<'tcx> Tree {
ProvenanceExtra::Wildcard => return Ok(()),
};
let global = machine.borrow_tracker.as_ref().unwrap();
self.perform_access(access_kind, tag, range, global)
let span = machine.current_span();
self.perform_access(access_kind, tag, range, global, span)
}
/// Check that this pointer has permission to deallocate this range.
@ -82,7 +80,8 @@ impl<'tcx> Tree {
ProvenanceExtra::Wildcard => return Ok(()),
};
let global = machine.borrow_tracker.as_ref().unwrap();
self.dealloc(tag, range, global)
let span = machine.current_span();
self.dealloc(tag, range, global, span)
}
pub fn expose_tag(&mut self, _tag: BorTag) {
@ -265,6 +264,7 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriInterpCxExt<'
.insert(new_tag, protect);
}
let span = this.machine.current_span();
let alloc_extra = this.get_alloc_extra(alloc_id)?;
let range = alloc_range(base_offset, ptr_size);
let mut tree_borrows = alloc_extra.borrow_tracker_tb().borrow_mut();
@ -272,14 +272,15 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriInterpCxExt<'
if new_perm.perform_read_access {
// Count this reborrow as a read access
let global = &this.machine.borrow_tracker.as_ref().unwrap();
tree_borrows.perform_access(AccessKind::Read, orig_tag, range, global)?;
let span = this.machine.current_span();
tree_borrows.perform_access(AccessKind::Read, orig_tag, range, global, span)?;
if let Some(data_race) = alloc_extra.data_race.as_ref() {
data_race.read(alloc_id, range, &this.machine)?;
}
}
// Record the parent-child pair in the tree.
tree_borrows.new_child(orig_tag, new_tag, new_perm.initial_state, range)?;
tree_borrows.new_child(orig_tag, new_tag, new_perm.initial_state, range, span)?;
Ok(Some((alloc_id, new_tag)))
}

208
src/tools/miri/src/borrow_tracker/tree_borrows/perms.rs
View File

@ -4,7 +4,7 @@ use std::fmt;
use crate::borrow_tracker::tree_borrows::tree::AccessRelatedness;
use crate::borrow_tracker::AccessKind;
/// The activation states of a pointer
/// The activation states of a pointer.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
enum PermissionPriv {
/// represents: a local reference that has not yet been written to;
@ -112,47 +112,14 @@ mod transition {
}
}
impl PermissionPriv {
/// Determines whether a transition that occurred is compatible with the presence
/// of a Protector. This is not included in the `transition` functions because
/// it would distract from the few places where the transition is modified
/// because of a protector, but not forbidden.
fn protector_allows_transition(self, new: Self) -> bool {
match (self, new) {
_ if self == new => true,
// It is always a protector violation to not be readable anymore
(_, Disabled) => false,
// In the case of a `Reserved` under a protector, both transitions
// `Reserved => Active` and `Reserved => Frozen` can legitimately occur.
// The first is standard (Child Write), the second is for Foreign Writes
// on protected Reserved where we must ensure that the pointer is not
// written to in the future.
(Reserved { .. }, Active) | (Reserved { .. }, Frozen) => true,
// This pointer should have stayed writeable for the whole function
(Active, Frozen) => false,
_ => unreachable!("Transition from {self:?} to {new:?} should never be possible"),
}
}
}
/// Public interface to the state machine that controls read-write permissions.
/// This is the "private `enum`" pattern.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub struct Permission(PermissionPriv);
impl fmt::Display for Permission {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(
f,
"{}",
match self.0 {
PermissionPriv::Reserved { .. } => "Reserved",
PermissionPriv::Active => "Active",
PermissionPriv::Frozen => "Frozen",
PermissionPriv::Disabled => "Disabled",
}
)
}
}
/// Transition from one permission to the next.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub struct PermTransition(PermissionPriv, PermissionPriv);
impl Permission {
/// Default initial permission of the root of a new tree.
@ -170,43 +137,148 @@ impl Permission {
Self(Frozen)
}
/// Pretty-printing. Needs to be here and not in diagnostics.rs
/// because `Self` is private.
pub fn short_name(self) -> &'static str {
// Make sure there are all of the same length as each other
// and also as `diagnostics::DisplayFmtPermission.uninit` otherwise
// alignment will be incorrect.
match self.0 {
Reserved { ty_is_freeze: true } => "Res",
Reserved { ty_is_freeze: false } => "Re*",
Active => "Act",
Frozen => "Frz",
Disabled => "Dis",
}
}
/// Check that there are no complaints from a possible protector.
///
/// Note: this is not in charge of checking that there *is* a protector,
/// it should be used as
/// ```
/// let no_protector_error = if is_protected(tag) {
/// old_perm.protector_allows_transition(new_perm)
/// };
/// ```
pub fn protector_allows_transition(self, new: Self) -> bool {
self.0.protector_allows_transition(new.0)
}
/// Apply the transition to the inner PermissionPriv.
pub fn perform_access(
kind: AccessKind,
rel_pos: AccessRelatedness,
old_perm: Self,
protected: bool,
) -> Option<Self> {
) -> Option<PermTransition> {
let old_state = old_perm.0;
transition::perform_access(kind, rel_pos, old_state, protected).map(Self)
transition::perform_access(kind, rel_pos, old_state, protected)
.map(|new_state| PermTransition(old_state, new_state))
}
}
impl PermTransition {
/// All transitions created through normal means (using `perform_access`)
/// should be possible, but the same is not guaranteed by construction of
/// transitions inferred by diagnostics. This checks that a transition
/// reconstructed by diagnostics is indeed one that could happen.
fn is_possible(old: PermissionPriv, new: PermissionPriv) -> bool {
old <= new
}
pub fn from(old: Permission, new: Permission) -> Option<Self> {
Self::is_possible(old.0, new.0).then_some(Self(old.0, new.0))
}
pub fn is_noop(self) -> bool {
self.0 == self.1
}
/// Extract result of a transition (checks that the starting point matches).
pub fn applied(self, starting_point: Permission) -> Option<Permission> {
(starting_point.0 == self.0).then_some(Permission(self.1))
}
/// Extract starting point of a transition
pub fn started(self) -> Permission {
Permission(self.0)
}
/// Determines whether a transition that occured is compatible with the presence
/// of a Protector. This is not included in the `transition` functions because
/// it would distract from the few places where the transition is modified
/// because of a protector, but not forbidden.
///
/// Note: this is not in charge of checking that there *is* a protector,
/// it should be used as
/// ```
/// let no_protector_error = if is_protected(tag) {
/// transition.is_allowed_by_protector()
/// };
/// ```
pub fn is_allowed_by_protector(&self) -> bool {
let &Self(old, new) = self;
assert!(Self::is_possible(old, new));
match (old, new) {
_ if old == new => true,
// It is always a protector violation to not be readable anymore
(_, Disabled) => false,
// In the case of a `Reserved` under a protector, both transitions
// `Reserved => Active` and `Reserved => Frozen` can legitimately occur.
// The first is standard (Child Write), the second is for Foreign Writes
// on protected Reserved where we must ensure that the pointer is not
// written to in the future.
(Reserved { .. }, Active) | (Reserved { .. }, Frozen) => true,
// This pointer should have stayed writeable for the whole function
(Active, Frozen) => false,
_ => unreachable!("Transition from {old:?} to {new:?} should never be possible"),
}
}
/// Composition function: get the transition that can be added after `app` to
/// produce `self`.
pub fn apply_start(self, app: Self) -> Option<Self> {
let new_start = app.applied(Permission(self.0))?;
Self::from(new_start, Permission(self.1))
}
}
pub mod diagnostics {
use super::*;
impl fmt::Display for PermissionPriv {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(
f,
"{}",
match self {
PermissionPriv::Reserved { .. } => "Reserved",
PermissionPriv::Active => "Active",
PermissionPriv::Frozen => "Frozen",
PermissionPriv::Disabled => "Disabled",
}
)
}
}
impl fmt::Display for PermTransition {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "from {} to {}", self.0, self.1)
}
}
impl fmt::Display for Permission {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{}", self.0)
}
}
impl Permission {
/// Abbreviated name of the permission (uniformly 3 letters for nice alignment).
pub fn short_name(self) -> &'static str {
// Make sure there are all of the same length as each other
// and also as `diagnostics::DisplayFmtPermission.uninit` otherwise
// alignment will be incorrect.
match self.0 {
Reserved { ty_is_freeze: true } => "Res",
Reserved { ty_is_freeze: false } => "Re*",
Active => "Act",
Frozen => "Frz",
Disabled => "Dis",
}
}
}
impl PermTransition {
/// Readable explanation of the consequences of an event.
/// Fits in the sentence "This accessed caused {trans.summary()}".
///
/// Important: for the purposes of this explanation, `Reserved` is considered
/// to have write permissions, because that's what the diagnostics care about
/// (otherwise `Reserved -> Frozen` would be considered a noop).
pub fn summary(&self) -> &'static str {
assert!(Self::is_possible(self.0, self.1));
match (self.0, self.1) {
(_, Active) => "an activation",
(_, Frozen) => "a loss of write permissions",
(Frozen, Disabled) => "a loss of read permissions",
(_, Disabled) => "a loss of read and write permissions",
(old, new) =>
unreachable!("Transition from {old:?} to {new:?} should never be possible"),
}
}
}
}

93
src/tools/miri/src/borrow_tracker/tree_borrows/tree.rs
View File

@ -14,10 +14,11 @@ use smallvec::SmallVec;
use rustc_const_eval::interpret::InterpResult;
use rustc_data_structures::fx::FxHashSet;
use rustc_span::Span;
use rustc_target::abi::Size;
use crate::borrow_tracker::tree_borrows::{
diagnostics::{NodeDebugInfo, TbError, TransitionError},
diagnostics::{self, NodeDebugInfo, TbError, TransitionError},
unimap::{UniEntry, UniIndex, UniKeyMap, UniValMap},
Permission,
};
@ -118,7 +119,7 @@ pub(super) struct Node {
/// Data given to the transition function
struct NodeAppArgs<'node> {
/// Node on which the transition is currently being applied
node: &'node Node,
node: &'node mut Node,
/// Mutable access to its permissions
perm: UniEntry<'node, LocationState>,
/// Relative position of the access
@ -131,14 +132,17 @@ struct ErrHandlerArgs<'node, InErr> {
/// Tag that triggered the error (not the tag that was accessed,
/// rather the parent tag that had insufficient permissions or the
/// non-parent tag that had a protector).
faulty_tag: &'node NodeDebugInfo,
conflicting_info: &'node NodeDebugInfo,
/// Information about the tag that was accessed just before the
/// error was triggered.
accessed_info: &'node NodeDebugInfo,
}
/// Internal contents of `Tree` with the minimum of mutable access for
/// the purposes of the tree traversal functions: the permissions (`perms`) can be
/// updated but not the tree structure (`tag_mapping` and `nodes`)
struct TreeVisitor<'tree> {
tag_mapping: &'tree UniKeyMap<BorTag>,
nodes: &'tree UniValMap<Node>,
nodes: &'tree mut UniValMap<Node>,
perms: &'tree mut UniValMap<LocationState>,
}
@ -167,6 +171,7 @@ impl<'tree> TreeVisitor<'tree> {
) -> Result<(), OutErr>
where {
struct TreeVisitAux<NodeApp, ErrHandler> {
accessed_tag: UniIndex,
f_propagate: NodeApp,
err_builder: ErrHandler,
stack: Vec<(UniIndex, AccessRelatedness)>,
@ -190,15 +195,21 @@ where {
rel_pos: AccessRelatedness,
) -> Result<(), OutErr> {
// 1. apply the propagation function
let node = this.nodes.get(tag).unwrap();
let node = this.nodes.get_mut(tag).unwrap();
let recurse =
(self.f_propagate)(NodeAppArgs { node, perm: this.perms.entry(tag), rel_pos })
.map_err(|error_kind| {
(self.err_builder)(ErrHandlerArgs {
error_kind,
faulty_tag: &node.debug_info,
conflicting_info: &this.nodes.get(tag).unwrap().debug_info,
accessed_info: &this
.nodes
.get(self.accessed_tag)
.unwrap()
.debug_info,
})
})?;
let node = this.nodes.get(tag).unwrap();
// 2. add the children to the stack for future traversal
if matches!(recurse, ContinueTraversal::Recurse) {
let child_rel = rel_pos.for_child();
@ -214,7 +225,8 @@ where {
}
let start_idx = self.tag_mapping.get(&start).unwrap();
let mut stack = TreeVisitAux { f_propagate, err_builder, stack: Vec::new() };
let mut stack =
TreeVisitAux { accessed_tag: start_idx, f_propagate, err_builder, stack: Vec::new() };
{
let mut path_ascend = Vec::new();
// First climb to the root while recording the path
@ -262,12 +274,15 @@ where {
impl Tree {
/// Create a new tree, with only a root pointer.
pub fn new(root_tag: BorTag, size: Size) -> Self {
pub fn new(root_tag: BorTag, size: Size, span: Span) -> Self {
let root_perm = Permission::new_root();
let mut tag_mapping = UniKeyMap::default();
let root_idx = tag_mapping.insert(root_tag);
let nodes = {
let mut nodes = UniValMap::<Node>::default();
let mut debug_info = NodeDebugInfo::new(root_tag, root_perm, span);
// name the root so that all allocations contain one named pointer
debug_info.add_name("root of the allocation");
nodes.insert(
root_idx,
Node {
@ -275,7 +290,7 @@ impl Tree {
parent: None,
children: SmallVec::default(),
default_initial_perm: root_perm,
debug_info: NodeDebugInfo::new(root_tag),
debug_info,
},
);
nodes
@ -297,6 +312,7 @@ impl<'tcx> Tree {
new_tag: BorTag,
default_initial_perm: Permission,
range: AllocRange,
span: Span,
) -> InterpResult<'tcx> {
assert!(!self.tag_mapping.contains_key(&new_tag));
let idx = self.tag_mapping.insert(new_tag);
@ -309,7 +325,7 @@ impl<'tcx> Tree {
parent: Some(parent_idx),
children: SmallVec::default(),
default_initial_perm,
debug_info: NodeDebugInfo::new(new_tag),
debug_info: NodeDebugInfo::new(new_tag, default_initial_perm, span),
},
);
// Register new_tag as a child of parent_tag
@ -330,11 +346,11 @@ impl<'tcx> Tree {
tag: BorTag,
range: AllocRange,
global: &GlobalState,
span: Span, // diagnostics
) -> InterpResult<'tcx> {
self.perform_access(AccessKind::Write, tag, range, global)?;
let access_info = &self.nodes.get(self.tag_mapping.get(&tag).unwrap()).unwrap().debug_info;
for (_range, perms) in self.rperms.iter_mut(range.start, range.size) {
TreeVisitor { nodes: &self.nodes, tag_mapping: &self.tag_mapping, perms }
self.perform_access(AccessKind::Write, tag, range, global, span)?;
for (offset, perms) in self.rperms.iter_mut(range.start, range.size) {
TreeVisitor { nodes: &mut self.nodes, tag_mapping: &self.tag_mapping, perms }
.traverse_parents_this_children_others(
tag,
|args: NodeAppArgs<'_>| -> Result<ContinueTraversal, TransitionError> {
@ -347,13 +363,14 @@ impl<'tcx> Tree {
Ok(ContinueTraversal::Recurse)
}
},
|args: ErrHandlerArgs<'_, TransitionError>| -> InterpErrorInfo<'tcx> {
let ErrHandlerArgs { error_kind, faulty_tag } = args;
|args: ErrHandlerArgs<'_, TransitionError>| -> InterpError<'tcx> {
let ErrHandlerArgs { error_kind, conflicting_info, accessed_info } = args;
TbError {
faulty_tag,
conflicting_info,
access_kind: AccessKind::Write,
error_offset: offset,
error_kind,
tag_of_access: access_info,
accessed_info,
}
.build()
},
@ -373,10 +390,10 @@ impl<'tcx> Tree {
tag: BorTag,
range: AllocRange,
global: &GlobalState,
span: Span, // diagnostics
) -> InterpResult<'tcx> {
let access_info = &self.nodes.get(self.tag_mapping.get(&tag).unwrap()).unwrap().debug_info;
for (_range, perms) in self.rperms.iter_mut(range.start, range.size) {
TreeVisitor { nodes: &self.nodes, tag_mapping: &self.tag_mapping, perms }
for (offset, perms) in self.rperms.iter_mut(range.start, range.size) {
TreeVisitor { nodes: &mut self.nodes, tag_mapping: &self.tag_mapping, perms }
.traverse_parents_this_children_others(
tag,
|args: NodeAppArgs<'_>| -> Result<ContinueTraversal, TransitionError> {
@ -424,24 +441,42 @@ impl<'tcx> Tree {
let old_perm = old_state.permission;
let protected = global.borrow().protected_tags.contains_key(&node.tag);
let new_perm =
let transition =
Permission::perform_access(access_kind, rel_pos, old_perm, protected)
.ok_or(TransitionError::ChildAccessForbidden(old_perm))?;
if protected
// Can't trigger Protector on uninitialized locations
&& old_state.initialized
&& !old_perm.protector_allows_transition(new_perm)
&& !transition.is_allowed_by_protector()
{
return Err(TransitionError::ProtectedTransition(old_perm, new_perm));
return Err(TransitionError::ProtectedTransition(transition));
}
// Record the event as part of the history
if !transition.is_noop() {
node.debug_info.history.push(diagnostics::Event {
transition,
access_kind,
access_range: range,
is_foreign: rel_pos.is_foreign(),
offset,
span,
});
old_state.permission =
transition.applied(old_state.permission).unwrap();
}
old_state.permission = new_perm;
old_state.initialized |= !rel_pos.is_foreign();
Ok(ContinueTraversal::Recurse)
},
|args: ErrHandlerArgs<'_, TransitionError>| -> InterpErrorInfo<'tcx> {
let ErrHandlerArgs { error_kind, faulty_tag } = args;
TbError { faulty_tag, access_kind, error_kind, tag_of_access: access_info }
.build()
|args: ErrHandlerArgs<'_, TransitionError>| -> InterpError<'tcx> {
let ErrHandlerArgs { error_kind, conflicting_info, accessed_info } = args;
TbError {
conflicting_info,
access_kind,
error_offset: offset,
error_kind,
accessed_info,
}
.build()
},
)?;
}

23
src/tools/miri/src/diagnostics.rs
View File

@ -7,6 +7,7 @@ use rustc_span::{source_map::DUMMY_SP, SpanData, Symbol};
use rustc_target::abi::{Align, Size};
use crate::borrow_tracker::stacked_borrows::diagnostics::TagHistory;
use crate::borrow_tracker::tree_borrows::diagnostics as tree_diagnostics;
use crate::*;
/// Details of premature program termination.
@ -23,8 +24,10 @@ pub enum TerminationInfo {
history: Option<TagHistory>,
},
TreeBorrowsUb {
msg: String,
// FIXME: incomplete
title: String,
relation: Option<String>,
problem: String,
history: tree_diagnostics::HistoryData,
},
Int2PtrWithStrictProvenance,
Deadlock,
@ -65,7 +68,7 @@ impl fmt::Display for TerminationInfo {
"integer-to-pointer casts and `ptr::from_exposed_addr` are not supported with `-Zmiri-strict-provenance`"
),
StackedBorrowsUb { msg, .. } => write!(f, "{msg}"),
TreeBorrowsUb { msg } => write!(f, "{msg}"),
TreeBorrowsUb { title, .. } => write!(f, "{title}"),
Deadlock => write!(f, "the evaluated program deadlocked"),
MultipleSymbolDefinitions { link_name, .. } =>
write!(f, "multiple definitions of symbol `{link_name}`"),
@ -219,10 +222,16 @@ pub fn report_error<'tcx, 'mir>(
}
helps
},
TreeBorrowsUb { .. } => {
let helps = vec![
(None, format!("this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental")),
];
TreeBorrowsUb { title: _, relation, problem, history } => {
let mut helps = Vec::new();
if let Some(relation) = relation {
helps.push((None, relation.clone()));
}
helps.push((None, problem.clone()));
helps.push((None, format!("this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental")));
for event in history.events.clone() {
helps.push(event);
}
helps
}
MultipleSymbolDefinitions { first, first_crate, second, second_crate, .. } =>

30
src/tools/miri/tests/fail/tree-borrows/alternate-read-write.stderr
View File

@ -1,11 +1,35 @@
error: Undefined Behavior: write access through <TAG> is forbidden because it is a child of <TAG> which is Frozen.
error: Undefined Behavior: write access through <TAG> is forbidden.
--> $DIR/alternate-read-write.rs:LL:CC
|
LL | *y += 1; // Failure
| ^^^^^^^ write access through <TAG> is forbidden because it is a child of <TAG> which is Frozen.
| ^^^^^^^ write access through <TAG> is forbidden.
|
= help: the accessed tag <TAG> is a child of the conflicting tag <TAG>.
= help: the conflicting tag <TAG> has state Frozen which forbids child write accesses.
= help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
= note: BACKTRACE:
help: the accessed tag <TAG> was created here.
--> $DIR/alternate-read-write.rs:LL:CC
|
LL | let y = unsafe { &mut *(x as *mut u8) };
| ^^^^^^^^^^^^^^^^^^^^
help: the conflicting tag <TAG> was created here, in the initial state Reserved.
--> $DIR/alternate-read-write.rs:LL:CC
|
LL | let y = unsafe { &mut *(x as *mut u8) };
| ^^^^^^^^^^^^^^^^^^^^
help: the conflicting tag <TAG> then transitioned from Reserved to Active due to a child write access at offsets [0x0..0x1].
--> $DIR/alternate-read-write.rs:LL:CC
|
LL | *y += 1; // Success
| ^^^^^^^
= help: this corresponds to an activation.
help: the conflicting tag <TAG> then transitioned from Active to Frozen due to a foreign read access at offsets [0x0..0x1].
--> $DIR/alternate-read-write.rs:LL:CC
|
LL | let _val = *x;
| ^^
= help: this corresponds to a loss of write permissions.
= note: BACKTRACE (of the first span):
= note: inside `main` at $DIR/alternate-read-write.rs:LL:CC
note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace

27
src/tools/miri/tests/fail/tree-borrows/error-range.rs Normal file
View File

@ -0,0 +1,27 @@
//@compile-flags: -Zmiri-tree-borrows
use core::ptr::addr_of_mut;
// Check that the diagnostics correctly report the exact range at fault
// and trim irrelevant events.
fn main() {
unsafe {
let data = &mut [0u8; 16];
// Create and activate a few bytes
let rmut = &mut *addr_of_mut!(data[0..6]);
rmut[3] += 1;
rmut[4] += 1;
rmut[5] += 1;
// Now make them lose some perms
let _v = data[3];
let _v = data[4];
let _v = data[5];
data[4] = 1;
data[5] = 1;
// Final test
rmut[5] += 1; //~ ERROR: /read access through .* is forbidden/
}
}

44
src/tools/miri/tests/fail/tree-borrows/error-range.stderr Normal file
View File

@ -0,0 +1,44 @@
error: Undefined Behavior: read access through <TAG> is forbidden.
--> $DIR/error-range.rs:LL:CC
|
LL | rmut[5] += 1;
| ^^^^^^^^^^^^ read access through <TAG> is forbidden.
|
= help: the accessed tag <TAG> is a child of the conflicting tag <TAG>.
= help: the conflicting tag <TAG> has state Disabled which forbids child read accesses.
= help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
help: the accessed tag <TAG> was created here.
--> $DIR/error-range.rs:LL:CC
|
LL | let rmut = &mut *addr_of_mut!(data[0..6]);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
help: the conflicting tag <TAG> was created here, in the initial state Reserved.
--> $DIR/error-range.rs:LL:CC
|
LL | let rmut = &mut *addr_of_mut!(data[0..6]);
| ^^^^
help: the conflicting tag <TAG> then transitioned from Reserved to Active due to a child write access at offsets [0x5..0x6].
--> $DIR/error-range.rs:LL:CC
|
LL | rmut[5] += 1;
| ^^^^^^^^^^^^
= help: this corresponds to an activation.
help: the conflicting tag <TAG> then transitioned from Active to Frozen due to a foreign read access at offsets [0x5..0x6].
--> $DIR/error-range.rs:LL:CC
|
LL | let _v = data[5];
| ^^^^^^^
= help: this corresponds to a loss of write permissions.
help: the conflicting tag <TAG> then transitioned from Frozen to Disabled due to a foreign write access at offsets [0x5..0x6].
--> $DIR/error-range.rs:LL:CC
|
LL | data[5] = 1;
| ^^^^^^^^^^^
= help: this corresponds to a loss of read permissions.
= note: BACKTRACE (of the first span):
= note: inside `main` at $DIR/error-range.rs:LL:CC
note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
error: aborting due to previous error

24
src/tools/miri/tests/fail/tree-borrows/fragile-data-race.stderr
View File

@ -1,11 +1,29 @@
error: Undefined Behavior: write access through <TAG> is forbidden because it is a child of <TAG> which is Frozen.
error: Undefined Behavior: write access through <TAG> is forbidden.
--> $DIR/fragile-data-race.rs:LL:CC
|
LL | unsafe { *p = 1 };
| ^^^^^^ write access through <TAG> is forbidden because it is a child of <TAG> which is Frozen.
| ^^^^^^ write access through <TAG> is forbidden.
|
= help: the accessed tag <TAG> is a child of the conflicting tag <TAG>.
= help: the conflicting tag <TAG> has state Frozen which forbids child write accesses.
= help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
= note: BACKTRACE:
help: the accessed tag <TAG> was created here.
--> $DIR/fragile-data-race.rs:LL:CC
|
LL | fn thread_1(x: &mut u8) -> SendPtr {
| ^
help: the conflicting tag <TAG> was created here, in the initial state Reserved.
--> RUSTLIB/std/src/panic.rs:LL:CC
|
LL | pub fn catch_unwind<F: FnOnce() -> R + UnwindSafe, R>(f: F) -> Result<R> {
| ^
help: the conflicting tag <TAG> then transitioned from Reserved to Frozen due to a foreign read access at offsets [0x0..0x1].
--> RUSTLIB/core/src/ptr/mod.rs:LL:CC
|
LL | crate::intrinsics::read_via_copy(src)
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
= help: this corresponds to a loss of write permissions.
= note: BACKTRACE (of the first span):
= note: inside `main` at $DIR/fragile-data-race.rs:LL:CC
note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace

18
src/tools/miri/tests/fail/tree-borrows/outside-range.stderr
View File

@ -1,11 +1,23 @@
error: Undefined Behavior: write access through <TAG> is forbidden because it is a foreign tag for <TAG>, which would hence change from Reserved to Disabled, but <TAG> is protected
error: Undefined Behavior: write access through <TAG> is forbidden.
--> $DIR/outside-range.rs:LL:CC
|
LL | *y.add(3) = 42;
| ^^^^^^^^^^^^^^ write access through <TAG> is forbidden because it is a foreign tag for <TAG>, which would hence change from Reserved to Disabled, but <TAG> is protected
| ^^^^^^^^^^^^^^ write access through <TAG> is forbidden.
|
= help: the accessed tag <TAG> is a foreign tag for the protected tag <TAG>.
= help: the access would cause the protected tag <TAG> to transition from Reserved to Disabled. This is a loss of read and write permissions, which is not allowed for protected tags.
= help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
= note: BACKTRACE:
help: the accessed tag <TAG> was created here.
--> $DIR/outside-range.rs:LL:CC
|
LL | let raw = data.as_mut_ptr();
| ^^^^^^^^^^^^^^^^^
help: the protected tag <TAG> was created here, in the initial state Reserved.
--> $DIR/outside-range.rs:LL:CC
|
LL | unsafe fn stuff(x: &mut u8, y: *mut u8) {
| ^
= note: BACKTRACE (of the first span):
= note: inside `stuff` at $DIR/outside-range.rs:LL:CC
note: inside `main`
--> $DIR/outside-range.rs:LL:CC

25
src/tools/miri/tests/fail/tree-borrows/read-to-local.stderr
View File

@ -1,12 +1,31 @@
error: Undefined Behavior: write access through <TAG> is forbidden because it is a child of <TAG> which is Frozen.
error: Undefined Behavior: write access through <TAG> is forbidden.
--> $DIR/read-to-local.rs:LL:CC
|
LL | *ptr = 0;
| ^^^^^^^^ write access through <TAG> is forbidden because it is a child of <TAG> which is Frozen.
| ^^^^^^^^ write access through <TAG> is forbidden.
|
= help: the accessed tag <TAG> has state Frozen which forbids child write accesses.
= help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
= note: BACKTRACE:
help: the accessed tag <TAG> was created here, in the initial state Reserved.
--> $DIR/read-to-local.rs:LL:CC
|
LL | let mref = &mut root;
| ^^^^^^^^^
help: the accessed tag <TAG> then transitioned from Reserved to Active due to a child write access at offsets [0x0..0x1].
--> $DIR/read-to-local.rs:LL:CC
|
LL | *ptr = 0; // Write
| ^^^^^^^^
= help: this corresponds to an activation.
help: the accessed tag <TAG> then transitioned from Active to Frozen due to a foreign read access at offsets [0x0..0x1].
--> $DIR/read-to-local.rs:LL:CC
|
LL | assert_eq!(root, 0); // Parent Read
| ^^^^^^^^^^^^^^^^^^^
= help: this corresponds to a loss of write permissions.
= note: BACKTRACE (of the first span):
= note: inside `main` at $DIR/read-to-local.rs:LL:CC
= note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace

29
src/tools/miri/tests/fail/tree-borrows/reserved/cell-protected-write.stderr
View File

@ -1,20 +1,33 @@
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Re*| └─┬──<TAG=base>
| Re*| ├─┬──<TAG=x>
| Re*| │ └─┬──<TAG=caller:x>
| Re*| │ └────<TAG=callee:x> Strongly protected
| Re*| └────<TAG=y,callee:y,caller:y>
| Act| └─┬──<TAG=root of the allocation>
| Re*| └─┬──<TAG=base>
| Re*| ├─┬──<TAG=x>
| Re*| │ └─┬──<TAG=caller:x>
| Re*| │ └────<TAG=callee:x> Strongly protected
| Re*| └────<TAG=y, callee:y, caller:y>
──────────────────────────────────────────────────────────────────────
error: Undefined Behavior: write access through <TAG> (also named 'y,callee:y,caller:y') is forbidden because it is a foreign tag for <TAG> (also named 'callee:x'), which would hence change from Reserved to Disabled, but <TAG> (also named 'callee:x') is protected
error: Undefined Behavior: write access through <TAG> (y, callee:y, caller:y) is forbidden.
--> $DIR/cell-protected-write.rs:LL:CC
|
LL | *y = 1;
| ^^^^^^ write access through <TAG> (also named 'y,callee:y,caller:y') is forbidden because it is a foreign tag for <TAG> (also named 'callee:x'), which would hence change from Reserved to Disabled, but <TAG> (also named 'callee:x') is protected
| ^^^^^^ write access through <TAG> (y, callee:y, caller:y) is forbidden.
|
= help: the accessed tag <TAG> (y, callee:y, caller:y) is a foreign tag for the protected tag <TAG> (callee:x).
= help: the access would cause the protected tag <TAG> (callee:x) to transition from Reserved to Disabled. This is a loss of read and write permissions, which is not allowed for protected tags.
= help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
= note: BACKTRACE:
help: the accessed tag <TAG> was created here.
--> $DIR/cell-protected-write.rs:LL:CC
|
LL | let y = (&mut *n).get();
| ^^^^^^^^^
help: the protected tag <TAG> was created here, in the initial state Reserved.
--> $DIR/cell-protected-write.rs:LL:CC
|
LL | unsafe fn write_second(x: &mut UnsafeCell<u8>, y: *mut u8) {
| ^
= note: BACKTRACE (of the first span):
= note: inside `main::write_second` at $DIR/cell-protected-write.rs:LL:CC
note: inside `main`
--> $DIR/cell-protected-write.rs:LL:CC

29
src/tools/miri/tests/fail/tree-borrows/reserved/int-protected-write.stderr
View File

@ -1,20 +1,33 @@
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Res| └─┬──<TAG=n>
| Res| ├─┬──<TAG=x>
| Res| │ └─┬──<TAG=caller:x>
| Res| │ └────<TAG=callee:x> Strongly protected
| Res| └────<TAG=y,callee:y,caller:y>
| Act| └─┬──<TAG=root of the allocation>
| Res| └─┬──<TAG=n>
| Res| ├─┬──<TAG=x>
| Res| │ └─┬──<TAG=caller:x>
| Res| │ └────<TAG=callee:x> Strongly protected
| Res| └────<TAG=y, callee:y, caller:y>
──────────────────────────────────────────────────────────────────────
error: Undefined Behavior: write access through <TAG> (also named 'y,callee:y,caller:y') is forbidden because it is a foreign tag for <TAG> (also named 'callee:x'), which would hence change from Reserved to Disabled, but <TAG> (also named 'callee:x') is protected
error: Undefined Behavior: write access through <TAG> (y, callee:y, caller:y) is forbidden.
--> $DIR/int-protected-write.rs:LL:CC
|
LL | *y = 0;
| ^^^^^^ write access through <TAG> (also named 'y,callee:y,caller:y') is forbidden because it is a foreign tag for <TAG> (also named 'callee:x'), which would hence change from Reserved to Disabled, but <TAG> (also named 'callee:x') is protected
| ^^^^^^ write access through <TAG> (y, callee:y, caller:y) is forbidden.
|
= help: the accessed tag <TAG> (y, callee:y, caller:y) is a foreign tag for the protected tag <TAG> (callee:x).
= help: the access would cause the protected tag <TAG> (callee:x) to transition from Reserved to Disabled. This is a loss of read and write permissions, which is not allowed for protected tags.
= help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
= note: BACKTRACE:
help: the accessed tag <TAG> was created here.
--> $DIR/int-protected-write.rs:LL:CC
|
LL | let y = (&mut *n) as *mut _;
| ^^^^^^^^^
help: the protected tag <TAG> was created here, in the initial state Reserved.
--> $DIR/int-protected-write.rs:LL:CC
|
LL | unsafe fn write_second(x: &mut u8, y: *mut u8) {
| ^
= note: BACKTRACE (of the first span):
= note: inside `main::write_second` at $DIR/int-protected-write.rs:LL:CC
note: inside `main`
--> $DIR/int-protected-write.rs:LL:CC

14
src/tools/miri/tests/fail/tree-borrows/strongly-protected.rs Normal file
View File

@ -0,0 +1,14 @@
//@compile-flags: -Zmiri-tree-borrows
//@error-pattern: /deallocation through .* is forbidden/
fn inner(x: &mut i32, f: fn(&mut i32)) {
// `f` may mutate, but it may not deallocate!
f(x)
}
fn main() {
inner(Box::leak(Box::new(0)), |x| {
let raw = x as *mut _;
drop(unsafe { Box::from_raw(raw) });
});
}

49
src/tools/miri/tests/fail/tree-borrows/strongly-protected.stderr Normal file
View File

@ -0,0 +1,49 @@
error: Undefined Behavior: deallocation through <TAG> is forbidden.
--> RUSTLIB/alloc/src/alloc.rs:LL:CC
|
LL | unsafe { __rust_dealloc(ptr, layout.size(), layout.align()) }
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocation through <TAG> is forbidden.
|
= help: the allocation of the accessed tag <TAG> also contains the strongly protected tag <TAG>.
= help: the strongly protected tag <TAG> disallows deallocations.
= help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
help: the accessed tag <TAG> was created here.
--> $DIR/strongly-protected.rs:LL:CC
|
LL | drop(unsafe { Box::from_raw(raw) });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
help: the strongly protected tag <TAG> was created here, in the initial state Reserved.
--> $DIR/strongly-protected.rs:LL:CC
|
LL | fn inner(x: &mut i32, f: fn(&mut i32)) {
| ^
= note: BACKTRACE (of the first span):
= note: inside `std::alloc::dealloc` at RUSTLIB/alloc/src/alloc.rs:LL:CC
= note: inside `<std::alloc::Global as std::alloc::Allocator>::deallocate` at RUSTLIB/alloc/src/alloc.rs:LL:CC
= note: inside `alloc::alloc::box_free::<i32, std::alloc::Global>` at RUSTLIB/alloc/src/alloc.rs:LL:CC
= note: inside `std::ptr::drop_in_place::<std::boxed::Box<i32>> - shim(Some(std::boxed::Box<i32>))` at RUSTLIB/core/src/ptr/mod.rs:LL:CC
= note: inside `std::mem::drop::<std::boxed::Box<i32>>` at RUSTLIB/core/src/mem/mod.rs:LL:CC
note: inside closure
--> $DIR/strongly-protected.rs:LL:CC
|
LL | drop(unsafe { Box::from_raw(raw) });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
= note: inside `<[closure@$DIR/strongly-protected.rs:LL:CC] as std::ops::FnOnce<(&mut i32,)>>::call_once - shim` at RUSTLIB/core/src/ops/function.rs:LL:CC
note: inside `inner`
--> $DIR/strongly-protected.rs:LL:CC
|
LL | f(x)
| ^^^^
note: inside `main`
--> $DIR/strongly-protected.rs:LL:CC
|
LL | / inner(Box::leak(Box::new(0)), |x| {
LL | | let raw = x as *mut _;
LL | | drop(unsafe { Box::from_raw(raw) });
LL | | });
| |______^
note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
error: aborting due to previous error

25
src/tools/miri/tests/fail/tree-borrows/write-during-2phase.stderr
View File

@ -1,11 +1,30 @@
error: Undefined Behavior: read access through <TAG> is forbidden because it is a child of <TAG> which is Disabled.
error: Undefined Behavior: read access through <TAG> is forbidden.
--> $DIR/write-during-2phase.rs:LL:CC
|
LL | fn add(&mut self, n: u64) -> u64 {
| ^^^^^^^^^ read access through <TAG> is forbidden because it is a child of <TAG> which is Disabled.
| ^^^^^^^^^ read access through <TAG> is forbidden.
|
= help: the accessed tag <TAG> has state Disabled which forbids child read accesses.
= help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
= note: BACKTRACE:
help: the accessed tag <TAG> was created here, in the initial state Reserved.
--> $DIR/write-during-2phase.rs:LL:CC
|
LL | let _res = f.add(unsafe {
| ________________^
LL | | let n = f.0;
LL | | // This is the access at fault, but it's not immediately apparent because
LL | | // the reference that got invalidated is not under a Protector.
LL | | *inner = 42;
LL | | n
LL | | });
| |______^
help: the accessed tag <TAG> then transitioned from Reserved to Disabled due to a foreign write access at offsets [0x0..0x8].
--> $DIR/write-during-2phase.rs:LL:CC
|
LL | *inner = 42;
| ^^^^^^^^^^^
= help: this corresponds to a loss of read and write permissions.
= note: BACKTRACE (of the first span):
= note: inside `Foo::add` at $DIR/write-during-2phase.rs:LL:CC
note: inside `main`
--> $DIR/write-during-2phase.rs:LL:CC

6
src/tools/miri/tests/pass/tree-borrows/cell-alternate-writes.stderr
View File

@ -1,10 +1,12 @@
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Re*| └────<TAG=data,x,y>
| Act| └─┬──<TAG=root of the allocation>
| Re*| └────<TAG=data, x, y>
──────────────────────────────────────────────────────────────────────
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Act| └────<TAG=data,x,y>
| Act| └─┬──<TAG=root of the allocation>
| Act| └────<TAG=data, x, y>
──────────────────────────────────────────────────────────────────────

36
src/tools/miri/tests/pass/tree-borrows/end-of-protector.stderr
View File

@ -1,32 +1,36 @@
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Res| └─┬──<TAG=data>
| Res| └────<TAG=x>
| Act| └─┬──<TAG=root of the allocation>
| Res| └─┬──<TAG=data>
| Res| └────<TAG=x>
──────────────────────────────────────────────────────────────────────
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Res| └─┬──<TAG=data>
| Res| └─┬──<TAG=x>
| Res| └─┬──<TAG=caller:x>
| Res| └────<TAG=callee:x> Strongly protected
| Act| └─┬──<TAG=root of the allocation>
| Res| └─┬──<TAG=data>
| Res| └─┬──<TAG=x>
| Res| └─┬──<TAG=caller:x>
| Res| └────<TAG=callee:x> Strongly protected
──────────────────────────────────────────────────────────────────────
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Res| └─┬──<TAG=data>
| Res| ├─┬──<TAG=x>
| Res| │ └─┬──<TAG=caller:x>
| Res| │ └────<TAG=callee:x>
| Res| └────<TAG=y>
| Act| └─┬──<TAG=root of the allocation>
| Res| └─┬──<TAG=data>
| Res| ├─┬──<TAG=x>
| Res| │ └─┬──<TAG=caller:x>
| Res| │ └────<TAG=callee:x>
| Res| └────<TAG=y>
──────────────────────────────────────────────────────────────────────
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Act| └─┬──<TAG=data>
| Dis| ├─┬──<TAG=x>
| Dis| │ └─┬──<TAG=caller:x>
| Dis| │ └────<TAG=callee:x>
| Act| └────<TAG=y>
| Act| └─┬──<TAG=root of the allocation>
| Act| └─┬──<TAG=data>
| Dis| ├─┬──<TAG=x>
| Dis| │ └─┬──<TAG=caller:x>
| Dis| │ └────<TAG=callee:x>
| Act| └────<TAG=y>
──────────────────────────────────────────────────────────────────────

48
src/tools/miri/tests/pass/tree-borrows/formatting.stderr
View File

@ -1,29 +1,31 @@
─────────────────────────────────────────────────────────────────────────────
───────────────────────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1.. 2.. 10.. 11..100..101..1000..1001..1024
| Res| Act| Res| Act| Res| Act| Res| Act| Res| └─┬──<TAG=data>
|----| Act|----|?Dis|----|?Dis| ----| ?Dis| ----| ├────<TAG=data[1]>
|----|----|----| Act|----|?Dis| ----| ?Dis| ----| ├────<TAG=data[10]>
|----|----|----|----|----| Frz| ----| ?Dis| ----| ├────<TAG=data[100]>
|----|----|----|----|----|----| ----| Act| ----| └────<TAG=data[1000]>
─────────────────────────────────────────────────────────────────────────────
| Act| Act| Act| Act| Act| Act| Act| Act| Act| └─┬──<TAG=root of the allocation>
| Res| Act| Res| Act| Res| Act| Res| Act| Res| └─┬──<TAG=data>
|----| Act|----|?Dis|----|?Dis| ----| ?Dis| ----| ├────<TAG=data[1]>
|----|----|----| Act|----|?Dis| ----| ?Dis| ----| ├────<TAG=data[10]>
|----|----|----|----|----| Frz| ----| ?Dis| ----| ├────<TAG=data[100]>
|----|----|----|----|----|----| ----| Act| ----| └────<TAG=data[1000]>
───────────────────────────────────────────────────────────────────────────────────────
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Frz| └─┬──<TAG=x>
| Frz| ├─┬──<TAG=xa>
| Frz| │ ├────<TAG=xaa>
| Frz| │ └────<TAG=xab>
| Frz| ├─┬──<TAG=xb>
| Frz| │ └─┬──<TAG=xba>
| Frz| │ └─┬──<TAG=xbaa>
| Frz| │ └─┬──<TAG=xbaaa>
| Frz| │ └────<TAG=xbaaaa>
| Frz| └─┬──<TAG=xc>
| Frz| ├─┬──<TAG=xca>
| Frz| │ ├────<TAG=xcaa>
| Frz| │ └────<TAG=xcab>
| Frz| └─┬──<TAG=xcb>
| Frz| ├────<TAG=xcba>
| Frz| └────<TAG=xcbb>
| Act| └─┬──<TAG=root of the allocation>
| Frz| └─┬──<TAG=x>
| Frz| ├─┬──<TAG=xa>
| Frz| │ ├────<TAG=xaa>
| Frz| │ └────<TAG=xab>
| Frz| ├─┬──<TAG=xb>
| Frz| │ └─┬──<TAG=xba>
| Frz| │ └─┬──<TAG=xbaa>
| Frz| │ └─┬──<TAG=xbaaa>
| Frz| │ └────<TAG=xbaaaa>
| Frz| └─┬──<TAG=xc>
| Frz| ├─┬──<TAG=xca>
| Frz| │ ├────<TAG=xcaa>
| Frz| │ └────<TAG=xcab>
| Frz| └─┬──<TAG=xcb>
| Frz| ├────<TAG=xcba>
| Frz| └────<TAG=xcbb>
──────────────────────────────────────────────────────────────────────

12
src/tools/miri/tests/pass/tree-borrows/reborrow-is-read.stderr
View File

@ -1,13 +1,15 @@
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Act| └─┬──<TAG=parent>
| Act| └────<TAG=x>
| Act| └─┬──<TAG=root of the allocation>
| Act| └─┬──<TAG=parent>
| Act| └────<TAG=x>
──────────────────────────────────────────────────────────────────────
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Act| └─┬──<TAG=parent>
| Frz| ├────<TAG=x>
| Res| └────<TAG=y>
| Act| └─┬──<TAG=root of the allocation>
| Act| └─┬──<TAG=parent>
| Frz| ├────<TAG=x>
| Res| └────<TAG=y>
──────────────────────────────────────────────────────────────────────

50
src/tools/miri/tests/pass/tree-borrows/reserved.stderr
View File

@ -2,51 +2,57 @@
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Re*| └─┬──<TAG=base>
| Re*| ├─┬──<TAG=x>
| Re*| │ └─┬──<TAG=caller:x>
| Frz| │ └────<TAG=callee:x>
| Re*| └────<TAG=y,caller:y,callee:y>
| Act| └─┬──<TAG=root of the allocation>
| Re*| └─┬──<TAG=base>
| Re*| ├─┬──<TAG=x>
| Re*| │ └─┬──<TAG=caller:x>
| Frz| │ └────<TAG=callee:x>
| Re*| └────<TAG=y, caller:y, callee:y>
──────────────────────────────────────────────────────────────────────
[interior mut] Foreign Read: Re* -> Re*
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 8
| Re*| └─┬──<TAG=base>
| Re*| ├────<TAG=x>
| Re*| └────<TAG=y>
| Act| └─┬──<TAG=root of the allocation>
| Re*| └─┬──<TAG=base>
| Re*| ├────<TAG=x>
| Re*| └────<TAG=y>
──────────────────────────────────────────────────────────────────────
[interior mut] Foreign Write: Re* -> Re*
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 8
| Act| └─┬──<TAG=base>
| Re*| ├────<TAG=x>
| Act| └────<TAG=y>
| Act| └─┬──<TAG=root of the allocation>
| Act| └─┬──<TAG=base>
| Re*| ├────<TAG=x>
| Act| └────<TAG=y>
──────────────────────────────────────────────────────────────────────
[protected] Foreign Read: Res -> Frz
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Res| └─┬──<TAG=base>
| Res| ├─┬──<TAG=x>
| Res| │ └─┬──<TAG=caller:x>
| Frz| │ └────<TAG=callee:x>
| Res| └────<TAG=y,caller:y,callee:y>
| Act| └─┬──<TAG=root of the allocation>
| Res| └─┬──<TAG=base>
| Res| ├─┬──<TAG=x>
| Res| │ └─┬──<TAG=caller:x>
| Frz| │ └────<TAG=callee:x>
| Res| └────<TAG=y, caller:y, callee:y>
──────────────────────────────────────────────────────────────────────
[] Foreign Read: Res -> Res
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Res| └─┬──<TAG=base>
| Res| ├────<TAG=x>
| Res| └────<TAG=y>
| Act| └─┬──<TAG=root of the allocation>
| Res| └─┬──<TAG=base>
| Res| ├────<TAG=x>
| Res| └────<TAG=y>
──────────────────────────────────────────────────────────────────────
[] Foreign Write: Res -> Dis
──────────────────────────────────────────────────────────────────────
Warning: this tree is indicative only. Some tags may have been hidden.
0.. 1
| Act| └─┬──<TAG=base>
| Dis| ├────<TAG=x>
| Act| └────<TAG=y>
| Act| └─┬──<TAG=root of the allocation>
| Act| └─┬──<TAG=base>
| Dis| ├────<TAG=x>
| Act| └────<TAG=y>
──────────────────────────────────────────────────────────────────────