Support on_crash & on_timeout callbacks for libafl_qemu modules (#2620)

* support (unsafe) on_crash / on_timeout callbacks for modules

* use libc types in bindgen

libafl_qemu/libafl_qemu_build/src/bindings.rs

@@ -181,6 +181,8 @@ pub fn generate(
         .allowlist_function("qemu_main_loop")
         .allowlist_function("qemu_cleanup")
         .blocklist_function("main_loop_wait") // bindgen issue #1313
+        .blocklist_type("siginfo_t")
+        .raw_line("use libc::siginfo_t;")
         .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()));
 
     // arch specific functions

libafl_qemu/libafl_qemu_sys/src/bindings/x86_64_stub_bindings.rs

@@ -1,7 +1,9 @@
-/* 1.83.0-nightly */
+/* 1.84.0-nightly */
-/* qemu git hash: d6637939526f453c69f4c6bfe4635feb5dc5c0be */
+/* qemu git hash: 805b14ffc44999952562e8f219d81c21a4fa50b9 */
 /* automatically generated by rust-bindgen 0.70.1 */
 
+use libc::siginfo_t;
+
 #[repr(C)]
 #[derive(Copy, Clone, Debug, Default, Eq, Hash, Ord, PartialEq, PartialOrd)]
 pub struct __BindgenBitfieldUnit<Storage> {
@@ -516,15 +518,6 @@ impl ::std::fmt::Debug for sigval {
 pub type __sigval_t = sigval;
 #[repr(C)]
 #[derive(Copy, Clone)]
-pub struct siginfo_t {
-    pub si_signo: ::std::os::raw::c_int,
-    pub si_errno: ::std::os::raw::c_int,
-    pub si_code: ::std::os::raw::c_int,
-    pub __pad0: ::std::os::raw::c_int,
-    pub _sifields: siginfo_t__bindgen_ty_1,
-}
-#[repr(C)]
-#[derive(Copy, Clone)]
 pub union siginfo_t__bindgen_ty_1 {
     pub _pad: [::std::os::raw::c_int; 28usize],
     pub _kill: siginfo_t__bindgen_ty_1__bindgen_ty_1,
@@ -827,31 +820,6 @@ impl ::std::fmt::Debug for siginfo_t__bindgen_ty_1 {
         write!(f, "siginfo_t__bindgen_ty_1 {{ union }}")
     }
 }
-#[allow(clippy::unnecessary_operation, clippy::identity_op)]
-const _: () = {
-    ["Size of siginfo_t"][::std::mem::size_of::<siginfo_t>() - 128usize];
-    ["Alignment of siginfo_t"][::std::mem::align_of::<siginfo_t>() - 8usize];
-    ["Offset of field: siginfo_t::si_signo"][::std::mem::offset_of!(siginfo_t, si_signo) - 0usize];
-    ["Offset of field: siginfo_t::si_errno"][::std::mem::offset_of!(siginfo_t, si_errno) - 4usize];
-    ["Offset of field: siginfo_t::si_code"][::std::mem::offset_of!(siginfo_t, si_code) - 8usize];
-    ["Offset of field: siginfo_t::__pad0"][::std::mem::offset_of!(siginfo_t, __pad0) - 12usize];
-    ["Offset of field: siginfo_t::_sifields"]
-        [::std::mem::offset_of!(siginfo_t, _sifields) - 16usize];
-};
-impl Default for siginfo_t {
-    fn default() -> Self {
-        let mut s = ::std::mem::MaybeUninit::<Self>::uninit();
-        unsafe {
-            ::std::ptr::write_bytes(s.as_mut_ptr(), 0, 1);
-            s.assume_init()
-        }
-    }
-}
-impl ::std::fmt::Debug for siginfo_t {
-    fn fmt(&self, f: &mut ::std::fmt::Formatter<'_>) -> ::std::fmt::Result {
-        write ! (f , "siginfo_t {{ si_signo: {:?}, si_errno: {:?}, si_code: {:?}, __pad0: {:?}, _sifields: {:?} }}" , self . si_signo , self . si_errno , self . si_code , self . __pad0 , self . _sifields)
-    }
-}
 pub type guint8 = ::std::os::raw::c_uchar;
 pub type gchar = ::std::os::raw::c_char;
 pub type guint = ::std::os::raw::c_uint;

libafl_qemu/runtime/libafl_qemu_stub_bindings.rs

@@ -1,5 +1,5 @@
-/* 1.83.0-nightly */
+/* 1.84.0-nightly */
-/* qemu git hash: d6637939526f453c69f4c6bfe4635feb5dc5c0be */
+/* qemu git hash: 805b14ffc44999952562e8f219d81c21a4fa50b9 */
 /* automatically generated by rust-bindgen 0.70.1 */
 
 pub const LIBAFL_SYNC_EXIT_OPCODE: u32 = 1727150607;

libafl_qemu/src/executor.rs

@@ -35,9 +35,6 @@ use libafl_bolts::{
 use libafl_qemu_sys::libafl_exit_request_timeout;
 #[cfg(emulation_mode = "usermode")]
 use libafl_qemu_sys::libafl_qemu_handle_crash;
-#[cfg(emulation_mode = "usermode")]
-use libafl_qemu_sys::siginfo_t;
-#[cfg(emulation_mode = "systemmode")]
 use libc::siginfo_t;
 
 #[cfg(emulation_mode = "usermode")]
@@ -60,17 +57,26 @@ where
 ///
 /// This should be used as a crash handler, and nothing else.
 #[cfg(emulation_mode = "usermode")]
-unsafe fn inproc_qemu_crash_handler(
+unsafe fn inproc_qemu_crash_handler<ET, S>(
     signal: Signal,
     info: &mut siginfo_t,
     mut context: Option<&mut ucontext_t>,
     _data: &mut InProcessExecutorHandlerData,
-) {
+) where
+    ET: EmulatorModuleTuple<S>,
+    S: UsesInput + Unpin,
+{
     let puc = match &mut context {
         Some(v) => ptr::from_mut::<ucontext_t>(*v) as *mut c_void,
         None => ptr::null_mut(),
     };
-    libafl_qemu_handle_crash(signal as i32, ptr::from_mut::<siginfo_t>(info), puc);
+
+    // run modules' crash callback
+    if let Some(emulator_modules) = EmulatorModules::<ET, S>::emulator_modules_mut() {
+        emulator_modules.modules_mut().on_crash_all();
+    }
+
+    libafl_qemu_handle_crash(signal as i32, info, puc);
 }
 
 #[cfg(emulation_mode = "systemmode")]
@@ -79,8 +85,7 @@ pub(crate) static BREAK_ON_TMOUT: AtomicBool = AtomicBool::new(false);
 /// # Safety
 /// Can call through the `unix_signal_handler::inproc_timeout_handler`.
 /// Calling this method multiple times concurrently can lead to race conditions.
-#[cfg(emulation_mode = "systemmode")]
+pub unsafe fn inproc_qemu_timeout_handler<E, EM, ET, OF, S, Z>(
-pub unsafe fn inproc_qemu_timeout_handler<E, EM, OF, Z>(
     signal: Signal,
     info: &mut siginfo_t,
     context: Option<&mut ucontext_t>,
@@ -88,16 +93,36 @@ pub unsafe fn inproc_qemu_timeout_handler<E, EM, OF, Z>(
 ) where
     E: HasObservers + HasInProcessHooks<E::State> + Executor<EM, Z>,
     E::Observers: ObserversTuple<E::Input, E::State>,
-    EM: EventFirer<State = E::State> + EventRestarter<State = E::State>,
-    OF: Feedback<EM, E::Input, E::Observers, E::State>,
     E::State: HasExecutions + HasSolutions + HasCorpus,
+    EM: EventFirer<State = E::State> + EventRestarter<State = E::State>,
+    ET: EmulatorModuleTuple<S>,
+    OF: Feedback<EM, E::Input, E::Observers, E::State>,
+    S: State + Unpin,
     Z: HasObjective<Objective = OF, State = E::State>,
     <<E as UsesState>::State as HasSolutions>::Solutions: Corpus<Input = E::Input>, //delete me
     <<<E as UsesState>::State as HasCorpus>::Corpus as Corpus>::Input: Clone,       //delete me
 {
+    #[cfg(emulation_mode = "systemmode")]
+    {
         if BREAK_ON_TMOUT.load(Ordering::Acquire) {
             libafl_exit_request_timeout();
         } else {
+            libafl::executors::hooks::unix::unix_signal_handler::inproc_timeout_handler::<
+                E,
+                EM,
+                OF,
+                Z,
+            >(signal, info, context, data);
+        }
+    }
+
+    #[cfg(emulation_mode = "usermode")]
+    {
+        // run modules' crash callback
+        if let Some(emulator_modules) = EmulatorModules::<ET, S>::emulator_modules_mut() {
+            emulator_modules.modules_mut().on_timeout_all();
+        }
+
         libafl::executors::hooks::unix::unix_signal_handler::inproc_timeout_handler::<E, EM, OF, Z>(
             signal, info, context, data,
         );
@@ -153,7 +178,8 @@ where
 
         #[cfg(emulation_mode = "usermode")]
         {
-            inner.inprocess_hooks_mut().crash_handler = inproc_qemu_crash_handler as *const c_void;
+            inner.inprocess_hooks_mut().crash_handler =
+                inproc_qemu_crash_handler::<ET, S> as *const c_void;
 
             let handler = |emulator_modules: &mut EmulatorModules<ET, S>, host_sig| {
                 eprintln!("Crashed with signal {host_sig}");
@@ -175,15 +201,14 @@ where
             }
         }
 
-        #[cfg(emulation_mode = "systemmode")]
-        {
         inner.inprocess_hooks_mut().timeout_handler = inproc_qemu_timeout_handler::<
             StatefulInProcessExecutor<'a, H, OT, S, Emulator<CM, ED, ET, S, SM>>,
             EM,
+            ET,
             OF,
+            S,
             Z,
         > as *const c_void;
-        }
 
         Ok(Self {
             inner,

libafl_qemu/src/modules/drcov.rs

@@ -108,6 +108,7 @@ pub struct DrCovModule<F> {
     full_trace: bool,
     drcov_len: usize,
 }
+
 impl DrCovModule<NopAddressFilter> {
     #[must_use]
     pub fn builder() -> DrCovModuleBuilder<NopAddressFilter> {
@@ -119,11 +120,7 @@ impl DrCovModule<NopAddressFilter> {
         }
     }
 }
-
+impl<F> DrCovModule<F> {
-impl<F> DrCovModule<F>
-where
-    F: AddressFilter,
-{
     #[must_use]
     #[allow(clippy::let_underscore_untyped)]
     pub fn new(
@@ -146,84 +143,7 @@ where
         }
     }
 
-    #[must_use]
+    pub fn write(&mut self) {
-    pub fn must_instrument(&self, addr: GuestAddr) -> bool {
-        self.filter.allowed(&addr)
-    }
-}
-
-impl<F, S> EmulatorModule<S> for DrCovModule<F>
-where
-    F: AddressFilter,
-    S: Unpin + UsesInput + HasMetadata,
-{
-    type ModuleAddressFilter = F;
-    #[cfg(emulation_mode = "systemmode")]
-    type ModulePageFilter = NopPageFilter;
-
-    fn init_module<ET>(&self, emulator_modules: &mut EmulatorModules<ET, S>)
-    where
-        ET: EmulatorModuleTuple<S>,
-    {
-        emulator_modules.blocks(
-            Hook::Function(gen_unique_block_ids::<ET, F, S>),
-            Hook::Function(gen_block_lengths::<ET, F, S>),
-            Hook::Function(exec_trace_block::<ET, F, S>),
-        );
-    }
-
-    #[cfg(emulation_mode = "usermode")]
-    fn first_exec<ET>(&mut self, emulator_modules: &mut EmulatorModules<ET, S>, _state: &mut S)
-    where
-        ET: EmulatorModuleTuple<S>,
-    {
-        if self.module_mapping.is_none() {
-            log::info!("Auto-filling module mapping for DrCov module from QEMU mapping.");
-
-            let qemu = emulator_modules.qemu();
-
-            let mut module_mapping: RangeMap<usize, (u16, String)> = RangeMap::new();
-
-            for (i, (r, p)) in qemu
-                .mappings()
-                .filter_map(|m| {
-                    m.path()
-                        .map(|p| ((m.start() as usize)..(m.end() as usize), p.to_string()))
-                        .filter(|(_, p)| !p.is_empty())
-                })
-                .enumerate()
-            {
-                module_mapping.insert(r, (i as u16, p));
-            }
-
-            self.module_mapping = Some(module_mapping);
-        } else {
-            log::info!("Using user-provided module mapping for DrCov module.");
-        }
-    }
-
-    #[cfg(emulation_mode = "systemmode")]
-    fn first_exec<ET>(&mut self, _emulator_modules: &mut EmulatorModules<ET, S>, _state: &mut S)
-    where
-        ET: EmulatorModuleTuple<S>,
-    {
-        assert!(
-            self.module_mapping.is_some(),
-            "DrCov should have a module mapping already set."
-        );
-    }
-
-    fn post_exec<OT, ET>(
-        &mut self,
-        _emulator_modules: &mut EmulatorModules<ET, S>,
-        _state: &mut S,
-        _input: &S::Input,
-        _observers: &mut OT,
-        _exit_kind: &mut ExitKind,
-    ) where
-        OT: ObserversTuple<S::Input, S>,
-        ET: EmulatorModuleTuple<S>,
-    {
         let lengths_opt = DRCOV_LENGTHS.lock().unwrap();
         let lengths = lengths_opt.as_ref().unwrap();
         if self.full_trace {
@@ -322,6 +242,100 @@ where
             self.drcov_len = DRCOV_MAP.lock().unwrap().as_ref().unwrap().len();
         }
     }
+}
+
+impl<F> DrCovModule<F>
+where
+    F: AddressFilter,
+{
+    #[must_use]
+    pub fn must_instrument(&self, addr: GuestAddr) -> bool {
+        self.filter.allowed(&addr)
+    }
+}
+
+impl<F, S> EmulatorModule<S> for DrCovModule<F>
+where
+    F: AddressFilter,
+    S: Unpin + UsesInput + HasMetadata,
+{
+    type ModuleAddressFilter = F;
+    #[cfg(emulation_mode = "systemmode")]
+    type ModulePageFilter = NopPageFilter;
+
+    fn init_module<ET>(&self, emulator_modules: &mut EmulatorModules<ET, S>)
+    where
+        ET: EmulatorModuleTuple<S>,
+    {
+        emulator_modules.blocks(
+            Hook::Function(gen_unique_block_ids::<ET, F, S>),
+            Hook::Function(gen_block_lengths::<ET, F, S>),
+            Hook::Function(exec_trace_block::<ET, F, S>),
+        );
+    }
+
+    #[cfg(emulation_mode = "usermode")]
+    fn first_exec<ET>(&mut self, emulator_modules: &mut EmulatorModules<ET, S>, _state: &mut S)
+    where
+        ET: EmulatorModuleTuple<S>,
+    {
+        if self.module_mapping.is_none() {
+            log::info!("Auto-filling module mapping for DrCov module from QEMU mapping.");
+
+            let qemu = emulator_modules.qemu();
+
+            let mut module_mapping: RangeMap<usize, (u16, String)> = RangeMap::new();
+
+            for (i, (r, p)) in qemu
+                .mappings()
+                .filter_map(|m| {
+                    m.path()
+                        .map(|p| ((m.start() as usize)..(m.end() as usize), p.to_string()))
+                        .filter(|(_, p)| !p.is_empty())
+                })
+                .enumerate()
+            {
+                module_mapping.insert(r, (i as u16, p));
+            }
+
+            self.module_mapping = Some(module_mapping);
+        } else {
+            log::info!("Using user-provided module mapping for DrCov module.");
+        }
+    }
+
+    #[cfg(emulation_mode = "systemmode")]
+    fn first_exec<ET>(&mut self, _emulator_modules: &mut EmulatorModules<ET, S>, _state: &mut S)
+    where
+        ET: EmulatorModuleTuple<S>,
+    {
+        assert!(
+            self.module_mapping.is_some(),
+            "DrCov should have a module mapping already set."
+        );
+    }
+
+    fn post_exec<OT, ET>(
+        &mut self,
+        _emulator_modules: &mut EmulatorModules<ET, S>,
+        _state: &mut S,
+        _input: &S::Input,
+        _observers: &mut OT,
+        _exit_kind: &mut ExitKind,
+    ) where
+        OT: ObserversTuple<S::Input, S>,
+        ET: EmulatorModuleTuple<S>,
+    {
+        self.write();
+    }
+
+    unsafe fn on_crash(&mut self) {
+        self.write();
+    }
+
+    unsafe fn on_timeout(&mut self) {
+        self.write();
+    }
 
     fn address_filter(&self) -> &Self::ModuleAddressFilter {
         &self.filter

libafl_qemu/src/modules/mod.rs

@@ -95,6 +95,16 @@ where
     {
     }
 
+    /// # Safety
+    ///
+    /// This is getting executed in a signal handler.
+    unsafe fn on_crash(&mut self) {}
+
+    /// # Safety
+    ///
+    /// This is getting executed in a signal handler.
+    unsafe fn on_timeout(&mut self) {}
+
     fn address_filter(&self) -> &Self::ModuleAddressFilter;
     fn address_filter_mut(&mut self) -> &mut Self::ModuleAddressFilter;
     fn update_address_filter(&mut self, qemu: Qemu, filter: Self::ModuleAddressFilter) {
@@ -149,6 +159,16 @@ where
         OT: ObserversTuple<S::Input, S>,
         ET: EmulatorModuleTuple<S>;
 
+    /// # Safety
+    ///
+    /// This is getting executed in a signal handler.
+    unsafe fn on_crash_all(&mut self);
+
+    /// # Safety
+    ///
+    /// This is getting executed in a signal handler.
+    unsafe fn on_timeout_all(&mut self);
+
     fn allow_address_range_all(&mut self, address_range: Range<GuestAddr>);
 
     #[cfg(emulation_mode = "systemmode")]
@@ -196,6 +216,10 @@ where
     {
     }
 
+    unsafe fn on_crash_all(&mut self) {}
+
+    unsafe fn on_timeout_all(&mut self) {}
+
     fn allow_address_range_all(&mut self, _address_range: Range<GuestAddr>) {}
 
     #[cfg(emulation_mode = "systemmode")]
@@ -255,6 +279,16 @@ where
             .post_exec_all(emulator_modules, state, input, observers, exit_kind);
     }
 
+    unsafe fn on_crash_all(&mut self) {
+        self.0.on_crash();
+        self.1.on_crash_all();
+    }
+
+    unsafe fn on_timeout_all(&mut self) {
+        self.0.on_timeout();
+        self.1.on_timeout_all();
+    }
+
     fn allow_address_range_all(&mut self, address_range: Range<GuestAddr>) {
         self.0.address_filter_mut().register(address_range.clone());
         self.1.allow_address_range_all(address_range);