1 files changed, 70 insertions, 67 deletions

diff --git a/toolkit/crashreporter/mozannotation_server/src/lib.rs b/toolkit/crashreporter/mozannotation_server/src/lib.rs
index 6ed5b3cc41..27682247f8 100644
--- a/toolkit/crashreporter/mozannotation_server/src/lib.rs
+++ b/toolkit/crashreporter/mozannotation_server/src/lib.rs
@@ -3,12 +3,18 @@
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 mod errors;
-mod process_reader;
 
 use crate::errors::*;
+#[cfg(any(target_os = "linux", target_os = "android"))]
+use memoffset::offset_of;
+use process_reader::error::ProcessReaderError;
 use process_reader::ProcessReader;
 
+#[cfg(any(target_os = "windows", target_os = "macos"))]
+use mozannotation_client::ANNOTATION_SECTION;
 use mozannotation_client::{Annotation, AnnotationContents, AnnotationMutex};
+#[cfg(any(target_os = "linux", target_os = "android"))]
+use mozannotation_client::{MozAnnotationNote, ANNOTATION_TYPE};
 use std::cmp::min;
 use std::iter::FromIterator;
 use std::mem::{size_of, ManuallyDrop};
@@ -29,12 +35,7 @@ pub struct CAnnotation {
     data: AnnotationData,
 }
 
-#[cfg(target_os = "windows")]
-type ProcessHandle = winapi::shared::ntdef::HANDLE;
-#[cfg(any(target_os = "linux", target_os = "android"))]
-type ProcessHandle = libc::pid_t;
-#[cfg(any(target_os = "macos"))]
-type ProcessHandle = mach2::mach_types::task_t;
+pub type ProcessHandle = process_reader::ProcessHandle;
 
 /// Return the annotations of a given process.
 ///
@@ -68,19 +69,23 @@ pub unsafe extern "C" fn mozannotation_free(ptr: *mut ThinVec<CAnnotation>) {
 pub fn retrieve_annotations(
     process: ProcessHandle,
     max_annotations: usize,
-) -> Result<Box<ThinVec<CAnnotation>>, RetrievalError> {
+) -> Result<Box<ThinVec<CAnnotation>>, AnnotationsRetrievalError> {
     let reader = ProcessReader::new(process)?;
-    let address = reader.find_annotations()?;
+    let address = find_annotations(&reader)?;
 
-    let mut mutex = reader.copy_object_shallow::<AnnotationMutex>(address)?;
+    let mut mutex = reader
+        .copy_object_shallow::<AnnotationMutex>(address)
+        .map_err(ProcessReaderError::from)?;
     let mutex = unsafe { mutex.assume_init_mut() };
 
     // TODO: we should clear the poison value here before getting the mutex
     // contents. Right now we have to fail if the mutex was poisoned.
-    let annotation_table = mutex.get_mut().map_err(|_e| RetrievalError::InvalidData)?;
+    let annotation_table = mutex
+        .get_mut()
+        .map_err(|_e| AnnotationsRetrievalError::InvalidData)?;
 
     if !annotation_table.verify() {
-        return Err(RetrievalError::InvalidAnnotationTable);
+        return Err(AnnotationsRetrievalError::InvalidAnnotationTable);
     }
 
     let vec_pointer = annotation_table.get_ptr();
@@ -97,8 +102,47 @@ pub fn retrieve_annotations(
     Ok(Box::new(annotations))
 }
 
+fn find_annotations(reader: &ProcessReader) -> Result<usize, AnnotationsRetrievalError> {
+    #[cfg(any(target_os = "linux", target_os = "android"))]
+    {
+        let libxul_address = reader.find_module("libxul.so")?;
+        let note_address = reader.find_program_note(
+            libxul_address,
+            ANNOTATION_TYPE,
+            size_of::<MozAnnotationNote>(),
+        )?;
+
+        let note = reader
+            .copy_object::<MozAnnotationNote>(note_address)
+            .map_err(ProcessReaderError::from)?;
+        let desc = note.desc;
+        let ehdr = (-note.ehdr) as usize;
+        let offset = desc + ehdr
+            - (offset_of!(MozAnnotationNote, ehdr) - offset_of!(MozAnnotationNote, desc));
+
+        usize::checked_add(libxul_address, offset).ok_or(AnnotationsRetrievalError::InvalidAddress)
+    }
+    #[cfg(any(target_os = "macos"))]
+    {
+        let libxul_address = reader.find_module("XUL")?;
+        reader
+            .find_section(libxul_address, ANNOTATION_SECTION)
+            .map_err(AnnotationsRetrievalError::from)
+    }
+    #[cfg(any(target_os = "windows"))]
+    {
+        let libxul_address = reader.find_module("xul.dll")?;
+        reader
+            .find_section(libxul_address, ANNOTATION_SECTION)
+            .map_err(AnnotationsRetrievalError::from)
+    }
+}
+
 // Read an annotation from the given address
-fn read_annotation(reader: &ProcessReader, address: usize) -> Result<CAnnotation, ReadError> {
+fn read_annotation(
+    reader: &ProcessReader,
+    address: usize,
+) -> Result<CAnnotation, process_reader::error::ReadError> {
     let raw_annotation = ManuallyDrop::new(reader.copy_object::<Annotation>(address)?);
     let mut annotation = CAnnotation {
         id: raw_annotation.id,
@@ -116,16 +160,16 @@ fn read_annotation(reader: &ProcessReader, address: usize) -> Result<CAnnotation
             annotation.data = AnnotationData::ByteBuffer(string);
         }
         AnnotationContents::CStringPointer => {
-            let buffer = copy_null_terminated_string_pointer(reader, raw_annotation.address)?;
-            annotation.data = AnnotationData::ByteBuffer(buffer);
+            let string = copy_null_terminated_string_pointer(reader, raw_annotation.address)?;
+            annotation.data = AnnotationData::ByteBuffer(string);
         }
         AnnotationContents::CString => {
-            let buffer = copy_null_terminated_string(reader, raw_annotation.address)?;
-            annotation.data = AnnotationData::ByteBuffer(buffer);
+            let string = copy_null_terminated_string(reader, raw_annotation.address)?;
+            annotation.data = AnnotationData::ByteBuffer(string);
         }
         AnnotationContents::ByteBuffer(size) | AnnotationContents::OwnedByteBuffer(size) => {
-            let buffer = copy_bytebuffer(reader, raw_annotation.address, size)?;
-            annotation.data = AnnotationData::ByteBuffer(buffer);
+            let string = copy_bytebuffer(reader, raw_annotation.address, size)?;
+            annotation.data = AnnotationData::ByteBuffer(string);
         }
     };
 
@@ -135,7 +179,7 @@ fn read_annotation(reader: &ProcessReader, address: usize) -> Result<CAnnotation
 fn copy_null_terminated_string_pointer(
     reader: &ProcessReader,
     address: usize,
-) -> Result<ThinVec<u8>, ReadError> {
+) -> Result<ThinVec<u8>, process_reader::error::ReadError> {
     let buffer_address = reader.copy_object::<usize>(address)?;
     copy_null_terminated_string(reader, buffer_address)
 }
@@ -143,56 +187,15 @@ fn copy_null_terminated_string_pointer(
 fn copy_null_terminated_string(
     reader: &ProcessReader,
     address: usize,
-) -> Result<ThinVec<u8>, ReadError> {
-    // Try copying the string word-by-word first, this is considerably faster
-    // than one byte at a time.
-    if let Ok(string) = copy_null_terminated_string_word_by_word(reader, address) {
-        return Ok(string);
-    }
-
-    // Reading the string one word at a time failed, let's try again one byte
-    // at a time. It's slow but it might work in situations where the string
-    // alignment causes word-by-word access to straddle page boundaries.
-    let mut length = 0;
-    let mut string = ThinVec::<u8>::new();
-
-    loop {
-        let char = reader.copy_object::<u8>(address + length)?;
-        length += 1;
-        string.push(char);
-
-        if char == 0 {
-            break;
-        }
-    }
-
-    Ok(string)
+) -> Result<ThinVec<u8>, process_reader::error::ReadError> {
+    let string = reader.copy_null_terminated_string(address)?;
+    Ok(ThinVec::<u8>::from(string.as_bytes()))
 }
 
-fn copy_null_terminated_string_word_by_word(
+fn copy_nscstring(
     reader: &ProcessReader,
     address: usize,
-) -> Result<ThinVec<u8>, ReadError> {
-    const WORD_SIZE: usize = size_of::<usize>();
-    let mut length = 0;
-    let mut string = ThinVec::<u8>::new();
-
-    loop {
-        let array = reader.copy_array::<u8>(address + length, WORD_SIZE)?;
-        let null_terminator = array.iter().position(|&e| e == 0);
-        length += null_terminator.unwrap_or(WORD_SIZE);
-        string.extend(array.into_iter());
-
-        if null_terminator.is_some() {
-            string.truncate(length);
-            break;
-        }
-    }
-
-    Ok(string)
-}
-
-fn copy_nscstring(reader: &ProcessReader, address: usize) -> Result<ThinVec<u8>, ReadError> {
+) -> Result<ThinVec<u8>, process_reader::error::ReadError> {
     // HACK: This assumes the layout of the nsCString object
     let length_address = address + size_of::<usize>();
     let length = reader.copy_object::<u32>(length_address)?;
@@ -211,7 +214,7 @@ fn copy_bytebuffer(
     reader: &ProcessReader,
     address: usize,
     size: u32,
-) -> Result<ThinVec<u8>, ReadError> {
+) -> Result<ThinVec<u8>, process_reader::error::ReadError> {
     let value = reader.copy_array::<u8>(address, size as _)?;
     Ok(ThinVec::<u8>::from_iter(value.into_iter()))
 }