Fix formatting and add ProvenanceMode enum

Author: carbotaniuman

src/bin/miri.rs

@@ -30,7 +30,7 @@ use rustc_middle::{
 };
 use rustc_session::{config::ErrorOutputType, search_paths::PathKind, CtfeBacktrace};
 
-use miri::BacktraceStyle;
+use miri::{BacktraceStyle, ProvenanceMode};
 
 struct MiriCompilerCalls {
     miri_config: miri::MiriConfig,
@@ -384,12 +384,12 @@ fn main() {
                     miri_config.tag_raw = true;
                 }
                 "-Zmiri-strict-provenance" => {
-                    miri_config.strict_provenance = true;
+                    miri_config.provenance_mode = ProvenanceMode::Strict;
                     miri_config.tag_raw = true;
                     miri_config.check_number_validity = true;
                 }
                 "-Zmiri-permissive-provenance" => {
-                    miri_config.permissive_provenance = true;
+                    miri_config.provenance_mode = ProvenanceMode::Permissive;
                     miri_config.tag_raw = true;
                 }
                 "-Zmiri-mute-stdout-stderr" => {

src/eval.rs

@@ -68,6 +68,19 @@ pub enum BacktraceStyle {
     Off,
 }
 
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub enum ProvenanceMode {
+    /// Int2ptr casts return pointers with "wildcard" provenance
+    /// that basically match that of all exposed pointers
+    /// (and SB tags, if enabled).
+    Permissive,
+    /// Int2ptr casts return pointers with an invalid provenance,
+    /// i.e., not valid for any memory access.
+    Strict,
+    /// Int2ptr casts return pointers valid for any allocation
+    Legacy,
+}
+
 /// Configuration needed to spawn a Miri instance.
 #[derive(Clone)]
 pub struct MiriConfig {
@@ -113,13 +126,8 @@ pub struct MiriConfig {
     pub panic_on_unsupported: bool,
     /// Which style to use for printing backtraces.
     pub backtrace_style: BacktraceStyle,
-    /// Whether to allow "permissive provenance" rules. Enabling this means int2ptr casts return
-    /// pointers with "wildcard" provenance that basically match that of all exposed pointers
-    /// (and SB tags, if enabled).
-    pub permissive_provenance: bool,
-    /// Whether to enforce "strict provenance" rules. Enabling this means int2ptr casts return
-    /// pointers with an invalid provenance, i.e., not valid for any memory access.
-    pub strict_provenance: bool,
+    /// Which provenance to use for int2ptr casts
+    pub provenance_mode: ProvenanceMode,
     /// Whether to ignore any output by the program. This is helpful when debugging miri
     /// as its messages don't get intermingled with the program messages.
     pub mute_stdout_stderr: bool,
@@ -148,8 +156,7 @@ impl Default for MiriConfig {
             measureme_out: None,
             panic_on_unsupported: false,
             backtrace_style: BacktraceStyle::Short,
-            permissive_provenance: false,
-            strict_provenance: false,
+            provenance_mode: ProvenanceMode::Legacy,
             mute_stdout_stderr: false,
         }
     }

src/intptrcast.rs

@@ -27,13 +27,8 @@ pub struct GlobalStateInner {
     /// This is used as a memory address when a new pointer is casted to an integer. It
     /// is always larger than any address that was previously made part of a block.
     next_base_addr: u64,
-    /// Whether to allow "permissive provenance" rules. Enabling this means int2ptr casts return
-    /// pointers with "wildcard" provenance that basically match that of all exposed pointers
-    /// (and SB tags, if enabled).
-    permissive_provenance: bool,
-    /// Whether to enforce "strict provenance" rules. Enabling this means int2ptr casts return
-    /// pointers with an invalid provenance, i.e., not valid for any memory access.
-    strict_provenance: bool,
+    /// The provenance to use for int2ptr casts
+    provenance_mode: ProvenanceMode,
 }
 
 impl GlobalStateInner {
@@ -43,8 +38,7 @@ impl GlobalStateInner {
             base_addr: FxHashMap::default(),
             exposed: FxHashSet::default(),
             next_base_addr: STACK_ADDR,
-            permissive_provenance: config.permissive_provenance,
-            strict_provenance: config.strict_provenance,
+            provenance_mode: config.provenance_mode,
         }
     }
 }
@@ -81,11 +75,12 @@ impl<'mir, 'tcx> GlobalStateInner {
                 }
             }
         }?;
-        
-        if global_state.permissive_provenance && !global_state.exposed.contains(&alloc_id) {
-            None
-        } else {
-            Some(alloc_id)
+
+        match global_state.provenance_mode {
+            ProvenanceMode::Legacy => Some(alloc_id),
+            ProvenanceMode::Permissive if global_state.exposed.contains(&alloc_id) =>
+                Some(alloc_id),
+            _ => None,
         }
     }
 
@@ -104,12 +99,14 @@ impl<'mir, 'tcx> GlobalStateInner {
         Self::ptr_from_casted_addr(ecx, addr)
     }
 
-    pub fn ptr_from_casted_addr(ecx: &MiriEvalContext<'mir, 'tcx>, addr: u64) -> Pointer<Option<Tag>> {
+    pub fn ptr_from_casted_addr(
+        ecx: &MiriEvalContext<'mir, 'tcx>,
+        addr: u64,
+    ) -> Pointer<Option<Tag>> {
         trace!("Casting 0x{:x} to a pointer", addr);
-        let global_state = ecx.machine.intptrcast.borrow();
 
         // Special-case NULL, it is always an invalid pointer.
-        if addr == 0 || global_state.strict_provenance {
+        if addr == 0 {
             return Pointer::new(None, Size::from_bytes(addr));
         }
 

src/lib.rs

@@ -75,7 +75,8 @@ pub use crate::diagnostics::{
     NonHaltingDiagnostic, TerminationInfo,
 };
 pub use crate::eval::{
-    create_ecx, eval_entry, AlignmentCheck, BacktraceStyle, IsolatedOp, MiriConfig, RejectOpWith,
+    create_ecx, eval_entry, AlignmentCheck, BacktraceStyle, IsolatedOp, MiriConfig, ProvenanceMode,
+    RejectOpWith,
 };
 pub use crate::helpers::EvalContextExt as HelpersEvalContextExt;
 pub use crate::machine::{