llvmbot wrote:

<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-lldb

Author: Med Ismail Bennani (medismailben)

<details>
<summary>Changes</summary>

This patch changes the way the main executable gets looked up when creating the 
target in the crashlog script.

On macOS, when a process crashes while being built from a user home directory, 
the path to the binary gets obfuscated in the crashlog to avoid revealing any 
user personal information like the username of even the user file system.

This safety feature breaks the main target creating lookup for crashlogs since 
the obfuscated path in the crashlog doesn't exists on disk.

This patch addresses this issue by speculatively patching the obfuscated binary 
patch and scanning every executable and subdirectories (in parallel) in said 
path, and looking for a matching UUID as the one provided in the crash report.

This usually enough to find the executable locally.

---
Full diff: https://github.com/llvm/llvm-project/pull/154975.diff


1 Files Affected:

- (modified) lldb/examples/python/crashlog.py (+100-5) 


``````````diff
diff --git a/lldb/examples/python/crashlog.py b/lldb/examples/python/crashlog.py
index b466be6a62428..d4cdd084a9830 100755
--- a/lldb/examples/python/crashlog.py
+++ b/lldb/examples/python/crashlog.py
@@ -38,6 +38,7 @@
 import plistlib
 import re
 import shlex
+import stat
 import string
 import subprocess
 import sys
@@ -320,9 +321,9 @@ def show_symbol_progress(self):
                 or self.path.startswith("/usr/lib/")
             )
 
-        def find_matching_slice(self):
+        def find_matching_slice(self, path):
             dwarfdump_cmd_output = subprocess.check_output(
-                'dwarfdump --uuid "%s"' % self.path, shell=True
+                'dwarfdump --uuid "%s"' % path, shell=True
             ).decode("utf-8")
             self_uuid = self.get_uuid()
             for line in dwarfdump_cmd_output.splitlines():
@@ -331,7 +332,7 @@ def find_matching_slice(self):
                     dwarf_uuid_str = match.group(1)
                     dwarf_uuid = uuid.UUID(dwarf_uuid_str)
                     if self_uuid == dwarf_uuid:
-                        self.resolved_path = self.path
+                        self.resolved_path = path
                         self.arch = match.group(2)
                         return True
             if not self.resolved_path:
@@ -340,11 +341,101 @@ def find_matching_slice(self):
                     print(
                         (
                             "error\n    error: unable to locate '%s' with UUID 
%s"
-                            % (self.path, self.get_normalized_uuid_string())
+                            % (path, self.get_normalized_uuid_string())
                         )
                     )
                 return False
 
+        def patch_binary_search_path(self):
+            home = os.path.expanduser("~")
+
+            patched_search_path = self.path.replace("/Users/USER", home)
+
+            if "*" in patched_search_path:
+                patched_search_path = patched_search_path[
+                    : patched_search_path.index("*")
+                ]
+
+            return patched_search_path
+
+        def find_binary_with_speculative_path(self, target_uuid):
+            search_path = self.patch_binary_search_path()
+
+            target_uuid = target_uuid.lower()
+            stop_flag = {"found": False}
+
+            with print_lock:
+                print(
+                    "Scanning for '%s' for '%s' ... (ˆC to interrupt)"
+                    % (search_path, os.path.basename(self.path))
+                )
+
+            def is_executable(path):
+                try:
+                    st = os.stat(path)
+                    return stat.S_ISREG(st.st_mode) and (
+                        st.st_mode & (stat.S_IXUSR | stat.S_IXGRP | 
stat.S_IXOTH)
+                    )
+                except:
+                    return False
+
+            def check_uuid(path, target_uuid):
+                try:
+                    output = subprocess.check_output(
+                        ["dwarfdump", "--uuid", path],
+                        text=True,
+                        stderr=subprocess.DEVNULL,
+                    )
+                    for line in output.splitlines():
+                        if target_uuid in line.lower():
+                            return path
+                except:
+                    return None
+                return None
+
+            def scan_directory_recursive(dirpath, target_uuid, stop_flag):
+                for root, _, files in os.walk(dirpath):
+                    if stop_flag.get("found"):
+                        break
+                    for name in files:
+                        path = os.path.join(root, name)
+                        if stop_flag.get("found"):
+                            break
+                        if is_executable(path):
+                            result = check_uuid(path, target_uuid)
+                            if result:
+                                stop_flag["found"] = True
+                                return result
+                return None
+
+            try:
+                subdirs = [
+                    os.path.join(search_path, d)
+                    for d in os.listdir(search_path)
+                    if os.path.isdir(os.path.join(search_path, d))
+                ]
+            except PermissionError:
+                subdirs = []
+
+            # Include root itself in case it contains files
+            subdirs.insert(0, search_path)
+
+            with concurrent.futures.ThreadPoolExecutor() as executor:
+                futures = {
+                    executor.submit(
+                        scan_directory_recursive, d, target_uuid, stop_flag
+                    ): d
+                    for d in subdirs
+                }
+                for fut in concurrent.futures.as_completed(futures):
+                    result = fut.result()
+                    if result:
+                        print("Found:", result)
+                        return result
+
+            print("No match found.")
+            return None
+
         def locate_module_and_debug_symbols(self):
             # Don't load a module twice...
             if self.resolved:
@@ -397,7 +488,11 @@ def locate_module_and_debug_symbols(self):
                                     if not os.path.exists(source_path):
                                         
unavailable_source_paths.add(source_path)
             if not self.resolved_path and os.path.exists(self.path):
-                if not self.find_matching_slice():
+                if not self.find_matching_slice(self.path):
+                    return False
+            speculative_path = self.find_binary_with_speculative_path(uuid_str)
+            if not self.resolved_path and os.path.exists(speculative_path):
+                if not self.find_matching_slice(speculative_path):
                     return False
             if not self.resolved_path and not os.path.exists(self.path):
                 try:

``````````

</details>


https://github.com/llvm/llvm-project/pull/154975
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