Verified Commit e3e84626 authored by ma1's avatar ma1
Browse files

Bug 2068421 - Make crash helper message reception more robust on Windows 

140esr patch version picked from
  https://hg.mozilla.org/try/rev/423bb0653100ac8c2fbbf8dcc73894a746ac12ba
parent d2f340fb

toolkit/crashreporter/crash_helper_common/src/ipc_queue.rs

+2 −0
Changes for toolkit/crashreporter/crash_helper_common/src/ipc_queue.rs: 2 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -30,6 +30,8 @@ pub enum IPCQueueError { 
    IPCListenerError(#[from] IPCListenerError),

    #[error("Underlying message error: {0}")]

    MessageError(#[from] MessageError),

    #[error("Unexpected event: {0}")]

    UnexpectedEvent(&'static str),

}



/*****************************************************************************

toolkit/crashreporter/crash_helper_common/src/ipc_queue/windows.rs

+33 −22
Changes for toolkit/crashreporter/crash_helper_common/src/ipc_queue/windows.rs: 33 added lines, 22 removed lines.
Original line number Diff line number Diff line
@@ -181,27 +181,8 @@ impl IPCQueue { 
                )

            };



            if number_of_bytes_transferred == 0 {

                // This is an event on the listener

                debug_assert!(

                    self.listener.as_raw() as IPCConnectorKey == completion_key,

                    "Completion event doesn't match the listener"

                );

                let operation = self.listen_operation.take();

                if let Some(operation) = operation {

                    operation

                        .accept()

                        .map_err(|_e| IPCQueueError::RegistrationFailure(0))?;

                }

                let connector = Rc::new(self.listener.replace_pipe()?);

                self.insert_connector(&connector);



                // After the pipe is connected the listener handle will have been

                // replaced with a new one, so associate the new handle with the

                // completion queue.

                self.add_handle(self.listener.as_raw())?;



                events.push(IPCEvent::Connect(connector));

            if self.is_listener(completion_key) {

                events.push(self.handle_listener_event(number_of_bytes_transferred)?);

            } else {

                let element = self

                    .connectors
@@ -211,7 +192,7 @@ impl IPCQueue { 
                    .operation

                    .take()

                    .expect("No pending receive operation");

                let buffer = &operation.collect_recv();

                let buffer = operation.collect_recv(number_of_bytes_transferred as usize);

                let header = Header::decode(buffer)?;

                let payload = element.connector.recv(header.size);

                match payload {
@@ -235,6 +216,36 @@ impl IPCQueue { 


        Ok(events)

    }



    fn is_listener(&self, completion_key: IPCConnectorKey) -> bool {

        self.listener.as_raw() as IPCConnectorKey == completion_key

    }



    fn handle_listener_event(

        &mut self,

        number_of_bytes_transferred: u32,

    ) -> Result<IPCEvent, IPCQueueError> {

        // A connection event will have 0 bytes transferred

        if number_of_bytes_transferred != 0 {

            return Err(IPCQueueError::UnexpectedEvent(

                "Non-zero transfer received on the listener",

            ));

        }



        let operation = self.listen_operation.take();

        if let Some(operation) = operation {

            operation.accept().map_err(|_e| IPCQueueError::RegistrationFailure(0))?;

        }

        let connector = Rc::new(self.listener.replace_pipe()?);

        self.insert_connector(&connector);



        // After the pipe is connected the listener handle will have been

        // replaced with a new one, so associate the new handle with the

        // completion queue.

        self.add_handle(self.listener.as_raw())?;



        Ok(IPCEvent::Connect(connector))

    }

}



impl Drop for IPCQueue {

toolkit/crashreporter/crash_helper_common/src/platform/windows.rs

+13 −2
Changes for toolkit/crashreporter/crash_helper_common/src/platform/windows.rs: 13 added lines, 2 removed lines.
Original line number Diff line number Diff line
@@ -325,8 +325,19 @@ impl OverlappedOperation { 
        Self::sched_recv_internal(handle, None, expected_size)

    }



    pub(crate) fn collect_recv(mut self) -> Vec<u8> {

        self.buffer.take().expect("Missing receive buffer")

    pub(crate) fn collect_recv(mut self, len: usize) -> Vec<u8> {

        let mut buffer = self.buffer.take().expect("Missing receive buffer");



        // We assert here because if this happens then we've hit a logic bug in

        // our code. The size of the receive operation and buffer length are

        // tied together so this should never happen.

        assert!(

            len <= buffer.len(),

            "More bytes received than the buffer would allow"

        );



        buffer.truncate(len);

        buffer

    }



    pub(crate) fn send(