https://github.com/medismailben created https://github.com/llvm/llvm-project/pull/154975
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. >From e4a9b130a337e712ad2d024a11b841778db68936 Mon Sep 17 00:00:00 2001 From: Med Ismail Bennani <ism...@bennani.ma> Date: Fri, 22 Aug 2025 09:09:34 -0700 Subject: [PATCH] [lldb/crashlog] Implement speculative binary lookup for target creation 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. Signed-off-by: Med Ismail Bennani <ism...@bennani.ma> --- lldb/examples/python/crashlog.py | 105 +++++++++++++++++++++++++++++-- 1 file changed, 100 insertions(+), 5 deletions(-) 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: _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits