The Tor Browser: config/find_OOM_errors.py@97036ab72558 (annotated)

config/find_OOM_errors.py@97036ab72558 (annotated)

config/find_OOM_errors.py

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 #!/usr/bin/env python
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 from __future__ import print_function
 usage = """%prog: A test for OOM conditions in the shell.
 %prog finds segfaults and other errors caused by incorrect handling of
 allocation during OOM (out-of-memory) conditions.
 """
 help = """Check for regressions only. This runs a set of files with a known
 number of OOM errors (specified by REGRESSION_COUNT), and exits with a non-zero
 result if more or less errors are found. See js/src/Makefile.in for invocation.
 """
 import hashlib
 import re
 import shlex
 import subprocess
 import sys
 import threading
 import time
 from optparse import OptionParser
 #####################################################################
 # Utility functions
 #####################################################################
 def run(args, stdin=None):
   class ThreadWorker(threading.Thread):
     def __init__(self, pipe):
       super(ThreadWorker, self).__init__()
       self.all = ""
       self.pipe = pipe
       self.setDaemon(True)
     def run(self):
       while True:
         line = self.pipe.readline()
         if line == '': break
         else:
           self.all += line
   try:
     if type(args) == str:
       args = shlex.split(args)
     args = [str(a) for a in args] # convert to strs
     stdin_pipe = subprocess.PIPE if stdin else None
     proc = subprocess.Popen(args, stdin=stdin_pipe, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
     if stdin_pipe:
       proc.stdin.write(stdin)
       proc.stdin.close()
     stdout_worker = ThreadWorker(proc.stdout)
     stderr_worker = ThreadWorker(proc.stderr)
     stdout_worker.start()
     stderr_worker.start()
     proc.wait()
     stdout_worker.join()
     stderr_worker.join()
   except KeyboardInterrupt as e:
     sys.exit(-1)
   stdout, stderr = stdout_worker.all, stderr_worker.all
   result = (stdout, stderr, proc.returncode)
   return result
 def get_js_files():
   (out, err, exit) = run('find ../jit-test/tests -name "*.js"')
   if (err, exit) != ("", 0):
     sys.exit("Wrong directory, run from an objdir")
   return out.split()
 #####################################################################
 # Blacklisting
 #####################################################################
 def in_blacklist(sig):
   return sig in blacklist
 def add_to_blacklist(sig):
   blacklist[sig] = blacklist.get(sig, 0)
   blacklist[sig] += 1
 # How often is a particular lines important for this.
 def count_lines():
   """Keep track of the amount of times individual lines occur, in order to
      prioritize the errors which occur most frequently."""
   counts = {}
   for string,count in blacklist.items():
     for line in string.split("\n"):
       counts[line] = counts.get(line, 0) + count
   lines = []
   for k,v in counts.items():
     lines.append("{0:6}: {1}".format(v, k))
   lines.sort()
   countlog = file("../OOM_count_log", "w")
   countlog.write("\n".join(lines))
   countlog.flush()
   countlog.close()
 #####################################################################
 # Output cleaning
 #####################################################################
 def clean_voutput(err):
   # Skip what we can't reproduce
   err = re.sub(r"^--\d+-- run: /usr/bin/dsymutil \"shell/js\"$", "", err, flags=re.MULTILINE)
   err = re.sub(r"^==\d+==", "", err, flags=re.MULTILINE)
   err = re.sub(r"^\*\*\d+\*\*", "", err, flags=re.MULTILINE)
   err = re.sub(r"^\s+by 0x[0-9A-Fa-f]+: ", "by: ", err, flags=re.MULTILINE)
   err = re.sub(r"^\s+at 0x[0-9A-Fa-f]+: ", "at: ", err, flags=re.MULTILINE)
   err = re.sub(r"(^\s+Address 0x)[0-9A-Fa-f]+( is not stack'd)", r"\1\2", err, flags=re.MULTILINE)
   err = re.sub(r"(^\s+Invalid write of size )\d+", r"\1x", err, flags=re.MULTILINE)
   err = re.sub(r"(^\s+Invalid read of size )\d+", r"\1x", err, flags=re.MULTILINE)
   err = re.sub(r"(^\s+Address 0x)[0-9A-Fa-f]+( is )\d+( bytes inside a block of size )[0-9,]+( free'd)", r"\1\2\3\4", err, flags=re.MULTILINE)
   # Skip the repeating bit due to the segfault
   lines = []
   for l in err.split('\n'):
     if l == " Process terminating with default action of signal 11 (SIGSEGV)":
       break
     lines.append(l)
   err = '\n'.join(lines)
   return err
 def remove_failed_allocation_backtraces(err):
   lines = []
   add = True
   for l in err.split('\n'):
     # Set start and end conditions for including text
     if l == " The site of the failed allocation is:":
       add = False
     elif l[:2] not in ['by: ', 'at:']:
       add = True
     if add:
       lines.append(l)
   err = '\n'.join(lines)
   return err
 def clean_output(err):
   err = re.sub(r"^js\(\d+,0x[0-9a-f]+\) malloc: \*\*\* error for object 0x[0-9a-f]+: pointer being freed was not allocated\n\*\*\* set a breakppoint in malloc_error_break to debug\n$", "pointer being freed was not allocated", err, flags=re.MULTILINE)
   return err
 #####################################################################
 # Consts, etc
 #####################################################################
 command_template = 'shell/js' \
                  + ' -m -j -p' \
                  + ' -e "const platform=\'darwin\'; const libdir=\'../jit-test/lib/\';"' \
                  + ' -f ../jit-test/lib/prolog.js' \
                  + ' -f {0}'
 # Blacklists are things we don't want to see in our logs again (though we do
 # want to count them when they happen). Whitelists we do want to see in our
 # logs again, principally because the information we have isn't enough.
 blacklist = {}
 add_to_blacklist(r"('', '', 1)") # 1 means OOM if the shell hasn't launched yet.
 add_to_blacklist(r"('', 'out of memory\n', 1)")
 whitelist = set()
 whitelist.add(r"('', 'out of memory\n', -11)") # -11 means OOM
 whitelist.add(r"('', 'out of memory\nout of memory\n', -11)")
 #####################################################################
 # Program
 #####################################################################
 # Options
 parser = OptionParser(usage=usage)
 parser.add_option("-r", "--regression", action="store", metavar="REGRESSION_COUNT", help=help,
                   type="int", dest="regression", default=None)
 (OPTIONS, args) = parser.parse_args()
 if OPTIONS.regression != None:
   # TODO: This should be expanded as we get a better hang of the OOM problems.
   # For now, we'll just check that the number of OOMs in one short file does not
   # increase.
   files = ["../jit-test/tests/arguments/args-createontrace.js"]
 else:
   files = get_js_files()
   # Use a command-line arg to reduce the set of files
   if len (args):
     files = [f for f in files if f.find(args[0]) != -1]
 if OPTIONS.regression == None:
   # Don't use a logfile, this is automated for tinderbox.
   log = file("../OOM_log", "w")
 num_failures = 0
 for f in files:
   # Run it once to establish boundaries
   command = (command_template + ' -O').format(f)
   out, err, exit = run(command)
   max = re.match(".*OOM max count: (\d+).*", out, flags=re.DOTALL).groups()[0]
   max = int(max)
   # OOMs don't recover well for the first 20 allocations or so.
   # TODO: revisit this.
   for i in range(20, max):
     if OPTIONS.regression == None:
       print("Testing allocation {0}/{1} in {2}".format(i,max,f))
     else:
       sys.stdout.write('.') # something short for tinderbox, no space or \n
     command = (command_template + ' -A {0}').format(f, i)
     out, err, exit = run(command)
     # Success (5 is SM's exit code for controlled errors)
     if exit == 5 and err.find("out of memory") != -1:
       continue
     # Failure
     else:
       if OPTIONS.regression != None:
         # Just count them
         num_failures += 1
         continue
       #########################################################################
       # The regression tests ends above. The rest of this is for running  the
       # script manually.
       #########################################################################
       problem = str((out, err, exit))
       if in_blacklist(problem) and problem not in whitelist:
         add_to_blacklist(problem)
         continue
       add_to_blacklist(problem)
       # Get valgrind output for a good stack trace
       vcommand = "valgrind --dsymutil=yes -q --log-file=OOM_valgrind_log_file " + command
       run(vcommand)
       vout = file("OOM_valgrind_log_file").read()
       vout = clean_voutput(vout)
       sans_alloc_sites = remove_failed_allocation_backtraces(vout)
       # Don't print duplicate information
       if in_blacklist(sans_alloc_sites):
         add_to_blacklist(sans_alloc_sites)
         continue
       add_to_blacklist(sans_alloc_sites)
       log.write ("\n")
       log.write ("\n")
       log.write ("=========================================================================")
       log.write ("\n")
       log.write ("An allocation failure at\n\tallocation {0}/{1} in {2}\n\t"
                  "causes problems (detected using bug 624094)"
                  .format(i, max, f))
       log.write ("\n")
       log.write ("\n")
       log.write ("Command (from obj directory, using patch from bug 624094):\n  " + command)
       log.write ("\n")
       log.write ("\n")
       log.write ("stdout, stderr, exitcode:\n  " + problem)
       log.write ("\n")
       log.write ("\n")
       double_free = err.find("pointer being freed was not allocated") != -1
       oom_detected = err.find("out of memory") != -1
       multiple_oom_detected = err.find("out of memory\nout of memory") != -1
       segfault_detected = exit == -11
       log.write ("Diagnosis: ")
       log.write ("\n")
       if multiple_oom_detected:
         log.write ("  - Multiple OOMs reported")
         log.write ("\n")
       if segfault_detected:
         log.write ("  - segfault")
         log.write ("\n")
       if not oom_detected:
         log.write ("  - No OOM checking")
         log.write ("\n")
       if double_free:
         log.write ("  - Double free")
         log.write ("\n")
       log.write ("\n")
       log.write ("Valgrind info:\n" + vout)
       log.write ("\n")
       log.write ("\n")
       log.flush()
   if OPTIONS.regression == None:
     count_lines()
 print()
 # Do the actual regression check
 if OPTIONS.regression != None:
   expected_num_failures = OPTIONS.regression
   if num_failures != expected_num_failures:
     print("TEST-UNEXPECTED-FAIL |", end='')
     if num_failures > expected_num_failures:
       print("More out-of-memory errors were found ({0}) than expected ({1}). "
             "This probably means an allocation site has been added without a "
             "NULL-check. If this is unavoidable, you can account for it by "
             "updating Makefile.in.".format(num_failures, expected_num_failures),
             end='')
     else:
       print("Congratulations, you have removed {0} out-of-memory error(s) "
             "({1} remain)! Please account for it by updating Makefile.in."
             .format(expected_num_failures - num_failures, num_failures),
             end='')
     sys.exit(-1)
   else:
     print('TEST-PASS | find_OOM_errors | Found the expected number of OOM '
           'errors ({0})'.format(expected_num_failures))

The Tor Browser / annotate

config/find_OOM_errors.py@97036ab72558 (annotated)

config/find_OOM_errors.py