[PATCH] scripts: add kasan_symbolize.py
From: Alexander Potapenko
Date: Wed Aug 10 2016 - 14:25:53 EST
Commit the script that symbolizes BUG messages and KASAN error reports
by adding file:line information to each stack frame.
The script is a copy of
https://github.com/google/sanitizers/blob/master/address-sanitizer/tools/kasan_symbolize.py
, originally written by Andrey Konovalov.
Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx>
---
MAINTAINERS | 1 +
scripts/kasan_symbolize.py | 321 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 322 insertions(+)
create mode 100755 scripts/kasan_symbolize.py
diff --git a/MAINTAINERS b/MAINTAINERS
index 20bb1d0..d5622ed 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6592,6 +6592,7 @@ F: include/linux/kasan*.h
F: lib/test_kasan.c
F: mm/kasan/
F: scripts/Makefile.kasan
+F: scripts/kasan_symbolize.py
KCONFIG
M: "Yann E. MORIN" <yann.morin.1998@xxxxxxx>
diff --git a/scripts/kasan_symbolize.py b/scripts/kasan_symbolize.py
new file mode 100755
index 0000000..067a2d1
--- /dev/null
+++ b/scripts/kasan_symbolize.py
@@ -0,0 +1,321 @@
+#!/usr/bin/python
+
+# Tool for symbolizing stack traces in BUG reports, mainly those produced
+# by KASAN.
+
+from collections import defaultdict
+import getopt
+import os
+import re
+import sys
+import subprocess
+
+# A hexadecimal number without the leading 0x.
+HEXNUM = '[0-9A-Fa-f]+'
+
+# An address in the form [<ffffffff12345678>].
+FRAME_ADDR = (
+ '(\[\<(?P<addr>' + HEXNUM + ')\>\])?\s*'
+)
+
+# A function name with an offset and function size, plus an optional module
+# name, e.g.:
+# __asan_load8+0x64/0x66
+FRAME_BODY = (
+ '(?P<body>' +
+ '(?P<function>[^\+]+)' +
+ '\+' +
+ '0x(?P<offset>' + HEXNUM + ')' +
+ '/' +
+ '0x(?P<size>' + HEXNUM + ')' +
+ '( \[(?P<module>.+)\])?' +
+ ')')
+
+# Matches the timestamp prefix of a log line.
+TIME_RE = re.compile(
+ '^(?P<time>\[[ ]*[0-9\.]+\]) ?(?P<body>.*)$'
+)
+
+# Matches a single stacktrace frame.
+FRAME_RE = re.compile(
+ '^' +
+ '(?P<prefix>[^\[\t]*)' +
+ FRAME_ADDR +
+ '( |\t)' +
+ '((?P<precise>\?) )?' +
+ FRAME_BODY +
+ '$'
+)
+
+# Matches the 'RIP:' line in BUG reports.
+RIP_RE = re.compile(
+ '^' +
+ '(?P<prefix>\s*RIP: ' + HEXNUM + ':\[[^]]+\]\s*)' +
+ FRAME_ADDR +
+ FRAME_BODY +
+ '$'
+)
+
+# Matches a single line of `nm -S` output.
+NM_RE = re.compile(
+ '^(?P<offset>' + HEXNUM + ') (?P<size>' + HEXNUM + ')' +
+ ' [a-zA-Z] (?P<symbol>[^ ]+)$'
+)
+
+
+class Symbolizer(object):
+ def __init__(self, binary_path):
+ self.proc = subprocess.Popen(
+ ['addr2line', '-f', '-i', '-e', binary_path],
+ stdin=subprocess.PIPE, stdout=subprocess.PIPE)
+
+ def __enter__(self):
+ return self
+
+ def __exit__(self, type, value, traceback):
+ self.close()
+
+ def process(self, addr):
+ self.proc.stdin.write(addr + '\n')
+ self.proc.stdin.write('ffffffffffffffff\n')
+ self.proc.stdin.flush()
+
+ result = []
+ while True:
+ func = self.proc.stdout.readline().rstrip()
+ fileline = self.proc.stdout.readline().rstrip()
+ if func == '??':
+ if len(result) == 0:
+ self.proc.stdout.readline()
+ self.proc.stdout.readline()
+ return result
+ result.append((func, fileline))
+
+ def close(self):
+ self.proc.kill()
+ self.proc.wait()
+
+
+def find_file(path, name):
+ path = os.path.expanduser(path)
+ for root, dirs, files in os.walk(path):
+ if name in files:
+ return os.path.join(root, name)
+ return None
+
+
+class SymbolOffsetLoader(object):
+ def __init__(self, binary_path):
+ output = subprocess.check_output(['nm', '-S', binary_path])
+ self.offsets = defaultdict(dict)
+ for line in output.split('\n'):
+ match = NM_RE.match(line)
+ if match != None:
+ offset = int(match.group('offset'), 16)
+ size = int(match.group('size'), 16)
+ # There can be several functions with similar names, but
+ # different sizes.
+ self.offsets[match.group('symbol')][size] = offset
+
+ def lookup_offset(self, symbol, size):
+ offsets = self.offsets.get(symbol)
+ if (offsets is None) or (size not in offsets):
+ return None
+ return offsets[size]
+
+
+class ReportProcessor(object):
+ def __init__(self, linux_path, strip_path):
+ self.strip_path = strip_path
+ self.linux_path = linux_path
+ self.module_symbolizers = {}
+ self.module_offset_loaders = {}
+ self.loaded_files = {}
+
+ def process_input(self, context_size, questionable):
+ for line in sys.stdin:
+ line = line.rstrip()
+ line = self.strip_time(line)
+ self.process_line(line, context_size, questionable)
+
+ def strip_time(self, line):
+ match = TIME_RE.match(line)
+ if match != None:
+ line = match.group('body')
+ return line
+
+ def process_line(self, line, context_size, questionable):
+ # |RIP_RE| is less general than |FRAME_RE|, so try it first.
+ match = None
+ for regexp in [RIP_RE, FRAME_RE]:
+ match = regexp.match(line)
+ if match:
+ break
+ if match == None:
+ print line
+ return
+
+ prefix = match.group('prefix')
+ addr = match.group('addr')
+ body = match.group('body')
+
+ precise = True
+ if 'precise' in match.groupdict().keys():
+ precise = not match.group('precise')
+ # Don't print frames with '?' until user asked otherwise.
+ if not precise and not questionable:
+ if '<EOI>' in match.group('prefix'):
+ print match.group('prefix')
+ return
+
+ function = match.group('function')
+ offset = match.group('offset')
+ size = match.group('size')
+ module = match.group('module')
+
+ if module == None:
+ module = 'vmlinux'
+ else:
+ module += '.ko'
+
+ if not self.load_module(module):
+ print line
+ return
+
+ symbolizer = self.module_symbolizers[module]
+ loader = self.module_offset_loaders[module]
+
+ symbol_offset = loader.lookup_offset(function, int(size, 16))
+ if symbol_offset is None:
+ print line
+ return
+
+ instruction_offset = int(offset, 16)
+ module_addr = hex(symbol_offset + instruction_offset - 1);
+
+ frames = symbolizer.process(module_addr)
+
+ if len(frames) == 0:
+ print line
+ return
+
+ for i, frame in enumerate(frames):
+ inlined = (i + 1 != len(frames))
+ func, fileline = frame[0], frame[1]
+ fileline = fileline.split(' (')[0] # strip ' (discriminator N)'
+ self.print_frame(inlined, precise, prefix, addr, func, fileline,
+ body)
+ self.print_lines(fileline, context_size)
+
+ def load_module(self, module):
+ if module in self.module_symbolizers.keys():
+ return True
+
+ module_path = find_file(self.linux_path, module)
+ if module_path == None:
+ return False
+
+ self.module_symbolizers[module] = Symbolizer(module_path)
+ self.module_offset_loaders[module] = SymbolOffsetLoader(module_path)
+ return True
+
+ def load_file(self, path):
+ if path in self.loaded_files.keys():
+ return self.loaded_files[path]
+ try:
+ with open(path) as f:
+ self.loaded_files[path] = f.readlines()
+ return self.loaded_files[path]
+ except:
+ return None
+
+ def print_frame(self, inlined, precise, prefix, addr, func, fileline, body):
+ if self.strip_path != None:
+ fileline_parts = fileline.split(self.strip_path, 1)
+ if len(fileline_parts) >= 2:
+ fileline = fileline_parts[1].lstrip('/')
+ if inlined:
+ addr = ' inline ';
+ body = func
+ elif addr == None:
+ addr = ' none ';
+ precise = '' if precise else '? '
+ print '%s[<%s>] %s%s %s' % (prefix, addr, precise, body, fileline)
+
+ def print_lines(self, fileline, context_size):
+ if context_size == 0:
+ return
+ fileline = fileline.split(':')
+ filename, linenum = fileline[0], fileline[1]
+
+ try:
+ linenum = int(linenum)
+ except:
+ return
+ assert linenum >= 0
+ if linenum == 0: # addr2line failed to restore correct line info
+ return
+ linenum -= 1 # addr2line reports line numbers starting with 1
+
+ start = max(0, linenum - context_size / 2)
+ end = start + context_size
+ lines = self.load_file(filename)
+ if not lines:
+ return
+
+ for i, line in enumerate(lines[start:end]):
+ print ' {0:5d} {1}'.format(i + start + 1, line),
+
+ def finalize(self):
+ for module, symbolizer in self.module_symbolizers.items():
+ symbolizer.close()
+
+
+def print_usage():
+ print 'Usage: {0} --linux=<linux path>'.format(sys.argv[0]),
+ print '[--strip=<strip path>]',
+ print '[--before=<lines before>]',
+ print '[--after=<lines after>]',
+ print '[--questionable]',
+ print
+
+
+def main():
+ try:
+ opts, args = getopt.getopt(sys.argv[1:], 'l:s:c:q:',
+ ['linux=', 'strip=', 'context=', 'questionable'])
+ except:
+ print_usage()
+ sys.exit(1)
+
+ linux_path = os.getcwd()
+ strip_path = os.getcwd()
+ context_size = 0
+ questionable = False
+
+ for opt, arg in opts:
+ if opt in ('-l', '--linux'):
+ linux_path = arg
+ elif opt in ('-s', '--strip'):
+ strip_path = arg
+ elif opt in ('-c', '--context'):
+ context_size = arg
+ elif opt in ('-q', '--questionable'):
+ questionable = True
+
+ try:
+ if isinstance(context_size, str):
+ context_size = int(context_size)
+ except:
+ print_usage()
+ sys.exit(1)
+
+ processor = ReportProcessor(linux_path, strip_path)
+ processor.process_input(context_size, questionable)
+ processor.finalize()
+
+ sys.exit(0)
+
+
+if __name__ == '__main__':
+ main()
--
2.8.0.rc3.226.g39d4020