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Commit 93ea0eb7 authored by Linus Torvalds's avatar Linus Torvalds
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Merge tag 'leaks-4.15-rc1' of git://github.com/tcharding/linux 

Pull leaking_addresses script updates from Tobin Harding:
 "Here are development patches for the leaking_addresses.pl script.

  Changes include:

   - add summary reporting to the script

   - add 'SigIgn' to false positives

   - add a file read timeout so the script doesn't block indefinitely

   - add infrastructure to enable multi-arch support and add support for ppc

   - add some exclude files/paths suggested by various people

   - code clean up and refactoring

   - overhaul command line options"

* tag 'leaks-4.15-rc1' of git://github.com/tcharding/linux:
  leaking_addresses: add SigIgn to false positives
  leaking_addresses: add timeout on file read
  leaking_addresses: add support for ppc64
  leaking_addresses: add summary reporting options
  leaking_addresses: add to exclude files/paths list
  leaking_addresses: fix comment string typo
  leaking_addresses: remove command line options
  leaking_addresses: remove dead/unused code
  leaking_addresses: use tabs instead of spaces
parents 7c225c69 a11949ec
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Showing with 283 additions and 87 deletions
scripts/leaking_addresses.pl
View file @ 93ea0eb7
......@@ -7,25 +7,6 @@
# - Scans dmesg output.
# - Walks directory tree and parses each file (for each directory in @DIRS).
#
# You can configure the behaviour of the script;
#
# - By adding paths, for directories you do not want to walk;
# absolute paths: @skip_walk_dirs_abs
# directory names: @skip_walk_dirs_any
#
# - By adding paths, for files you do not want to parse;
# absolute paths: @skip_parse_files_abs
# file names: @skip_parse_files_any
#
# The use of @skip_xxx_xxx_any causes files to be skipped where ever they occur.
# For example adding 'fd' to @skip_walk_dirs_any causes the fd/ directory to be
# skipped for all PID sub-directories of /proc
#
# The same thing can be achieved by passing command line options to --dont-walk
# and --dont-parse. If absolute paths are supplied to these options they are
# appended to the @skip_xxx_xxx_abs arrays. If file names are supplied to these
# options, they are appended to the @skip_xxx_xxx_any arrays.
#
# Use --debug to output path before parsing, this is useful to find files that
# cause the script to choke.
#
......@@ -40,6 +21,7 @@ use File::Spec;
use Cwd 'abs_path';
use Term::ANSIColor qw(:constants);
use Getopt::Long qw(:config no_auto_abbrev);
use Config;
my $P = $0;
my $V = '0.01';
......@@ -47,21 +29,36 @@ my $V = '0.01';
# Directories to scan.
my @DIRS = ('/proc', '/sys');
# Timer for parsing each file, in seconds.
my $TIMEOUT = 10;
# Script can only grep for kernel addresses on the following architectures. If
# your architecture is not listed here and has a grep'able kernel address please
# consider submitting a patch.
my @SUPPORTED_ARCHITECTURES = ('x86_64', 'ppc64');
# Command line options.
my $help = 0;
my $debug = 0;
my @dont_walk = ();
my @dont_parse = ();
my $raw = 0;
my $output_raw = ""; # Write raw results to file.
my $input_raw = ""; # Read raw results from file instead of scanning.
my $suppress_dmesg = 0; # Don't show dmesg in output.
my $squash_by_path = 0; # Summary report grouped by absolute path.
my $squash_by_filename = 0; # Summary report grouped by filename.
# Do not parse these files (absolute path).
my @skip_parse_files_abs = ('/proc/kmsg',
'/proc/kcore',
'/proc/fs/ext4/sdb1/mb_groups',
'/proc/1/fd/3',
'/sys/firmware/devicetree',
'/proc/device-tree',
'/sys/kernel/debug/tracing/trace_pipe',
'/sys/kernel/security/apparmor/revision');
# Do not parse thes files under any subdirectory.
# Do not parse these files under any subdirectory.
my @skip_parse_files_any = ('0',
'1',
'2',
......@@ -82,6 +79,7 @@ my @skip_walk_dirs_any = ('self',
'thread-self',
'cwd',
'fd',
'usbmon',
'stderr',
'stdin',
'stdout');
......@@ -91,24 +89,31 @@ sub help
my ($exitcode) = @_;
print << "EOM";
Usage: $P [OPTIONS]
Version: $V
Options:
--dont-walk=<dir> Don't walk tree starting at <dir>.
--dont-parse=<file> Don't parse <file>.
-o, --output-raw=<file> Save results for future processing.
-i, --input-raw=<file> Read results from file instead of scanning.
--raw Show raw results (default).
--suppress-dmesg Do not show dmesg results.
--squash-by-path Show one result per unique path.
--squash-by-filename Show one result per unique filename.
-d, --debug Display debugging output.
-h, --help, --version Display this help and exit.
If an absolute path is passed to --dont_XXX then this path is skipped. If a
single filename is passed then this file/directory will be skipped when
appearing under any subdirectory.
Examples:
Example:
# Scan kernel and dump raw results.
$0
# Just scan dmesg output.
scripts/leaking_addresses.pl --dont_walk_abs /proc --dont_walk_abs /sys
# Scan kernel and save results to file.
$0 --output-raw scan.out
# View summary report.
$0 --input-raw scan.out --squash-by-filename
Scans the running (64 bit) kernel for potential leaking addresses.
......@@ -117,55 +122,82 @@ EOM
}
GetOptions(
'dont-walk=s' => \@dont_walk,
'dont-parse=s' => \@dont_parse,
'd|debug' => \$debug,
'h|help' => \$help,
'version' => \$help
'version' => \$help,
'o|output-raw=s' => \$output_raw,
'i|input-raw=s' => \$input_raw,
'suppress-dmesg' => \$suppress_dmesg,
'squash-by-path' => \$squash_by_path,
'squash-by-filename' => \$squash_by_filename,
'raw' => \$raw,
) or help(1);
help(0) if ($help);
push_to_global();
if ($input_raw) {
format_output($input_raw);
exit(0);
}
if (!$input_raw and ($squash_by_path or $squash_by_filename)) {
printf "\nSummary reporting only available with --input-raw=<file>\n";
printf "(First run scan with --output-raw=<file>.)\n";
exit(128);
}
if (!is_supported_architecture()) {
printf "\nScript does not support your architecture, sorry.\n";
printf "\nCurrently we support: \n\n";
foreach(@SUPPORTED_ARCHITECTURES) {
printf "\t%s\n", $_;
}
my $archname = $Config{archname};
printf "\n\$ perl -MConfig -e \'print \"\$Config{archname}\\n\"\'\n";
printf "%s\n", $archname;
exit(129);
}
if ($output_raw) {
open my $fh, '>', $output_raw or die "$0: $output_raw: $!\n";
select $fh;
}
parse_dmesg();
walk(@DIRS);
exit 0;
sub debug_arrays
sub dprint
{
print 'dirs_any: ' . join(", ", @skip_walk_dirs_any) . "\n";
print 'dirs_abs: ' . join(", ", @skip_walk_dirs_abs) . "\n";
print 'parse_any: ' . join(", ", @skip_parse_files_any) . "\n";
print 'parse_abs: ' . join(", ", @skip_parse_files_abs) . "\n";
printf(STDERR @_) if $debug;
}
sub dprint
sub is_supported_architecture
{
printf(STDERR @_) if $debug;
return (is_x86_64() or is_ppc64());
}
sub push_in_abs_any
sub is_x86_64
{
my ($in, $abs, $any) = @_;
my $archname = $Config{archname};
foreach my $path (@$in) {
if (File::Spec->file_name_is_absolute($path)) {
push @$abs, $path;
} elsif (index($path,'/') == -1) {
push @$any, $path;
} else {
print 'path error: ' . $path;
}
if ($archname =~ m/x86_64/) {
return 1;
}
return 0;
}
# Push command line options to global arrays.
sub push_to_global
sub is_ppc64
{
push_in_abs_any(\@dont_walk, \@skip_walk_dirs_abs, \@skip_walk_dirs_any);
push_in_abs_any(\@dont_parse, \@skip_parse_files_abs, \@skip_parse_files_any);
my $archname = $Config{archname};
if ($archname =~ m/powerpc/ and $archname =~ m/64/) {
return 1;
}
return 0;
}
sub is_false_positive
......@@ -177,11 +209,13 @@ sub is_false_positive
return 1;
}
if (is_x86_64) {
# vsyscall memory region, we should probably check against a range here.
if ($match =~ '\bf{10}600000\b' or
$match =~ '\bf{10}601000\b') {
return 1;
}
}
return 0;
}
......@@ -190,10 +224,11 @@ sub is_false_positive
sub may_leak_address
{
my ($line) = @_;
my $address = '\b(0x)?ffff[[:xdigit:]]{12}\b';
my $address_re;
# Signal masks.
if ($line =~ '^SigBlk:' or
$line =~ '^SigIgn:' or
$line =~ '^SigCgt:') {
return 0;
}
......@@ -203,7 +238,14 @@ sub may_leak_address
return 0;
}
while (/($address)/g) {
# One of these is guaranteed to be true.
if (is_x86_64()) {
$address_re = '\b(0x)?ffff[[:xdigit:]]{12}\b';
} elsif (is_ppc64()) {
$address_re = '\b(0x)?[89abcdef]00[[:xdigit:]]{13}\b';
}
while (/($address_re)/g) {
if (!is_false_positive($1)) {
return 1;
}
......@@ -246,6 +288,23 @@ sub skip_parse
return skip($path, \@skip_parse_files_abs, \@skip_parse_files_any);
}
sub timed_parse_file
{
my ($file) = @_;
eval {
local $SIG{ALRM} = sub { die "alarm\n" }; # NB: \n required.
alarm $TIMEOUT;
parse_file($file);
alarm 0;
};
if ($@) {
die unless $@ eq "alarm\n"; # Propagate unexpected errors.
printf STDERR "timed out parsing: %s\n", $file;
}
}
sub parse_file
{
my ($file) = @_;
......@@ -281,7 +340,6 @@ sub skip_walk
sub walk
{
my @dirs = @_;
my %seen;
while (my $pwd = shift @dirs) {
next if (skip_walk($pwd));
......@@ -298,8 +356,146 @@ sub walk
if (-d $path) {
push @dirs, $path;
} else {
parse_file($path);
timed_parse_file($path);
}
}
}
}
sub format_output
{
my ($file) = @_;
# Default is to show raw results.
if ($raw or (!$squash_by_path and !$squash_by_filename)) {
dump_raw_output($file);
return;
}
my ($total, $dmesg, $paths, $files) = parse_raw_file($file);
printf "\nTotal number of results from scan (incl dmesg): %d\n", $total;
if (!$suppress_dmesg) {
print_dmesg($dmesg);
}
if ($squash_by_filename) {
squash_by($files, 'filename');
}
if ($squash_by_path) {
squash_by($paths, 'path');
}
}
sub dump_raw_output
{
my ($file) = @_;
open (my $fh, '<', $file) or die "$0: $file: $!\n";
while (<$fh>) {
if ($suppress_dmesg) {
if ("dmesg:" eq substr($_, 0, 6)) {
next;
}
}
print $_;
}
close $fh;
}
sub parse_raw_file
{
my ($file) = @_;
my $total = 0; # Total number of lines parsed.
my @dmesg; # dmesg output.
my %files; # Unique filenames containing leaks.
my %paths; # Unique paths containing leaks.
open (my $fh, '<', $file) or die "$0: $file: $!\n";
while (my $line = <$fh>) {
$total++;
if ("dmesg:" eq substr($line, 0, 6)) {
push @dmesg, $line;
next;
}
cache_path(\%paths, $line);
cache_filename(\%files, $line);
}
return $total, \@dmesg, \%paths, \%files;
}
sub print_dmesg
{
my ($dmesg) = @_;
print "\ndmesg output:\n";
if (@$dmesg == 0) {
print "<no results>\n";
return;
}
foreach(@$dmesg) {
my $index = index($_, ': ');
$index += 2; # skid ': '
print substr($_, $index);
}
}
sub squash_by
{
my ($ref, $desc) = @_;
print "\nResults squashed by $desc (excl dmesg). ";
print "Displaying [<number of results> <$desc>], <example result>\n";
if (keys %$ref == 0) {
print "<no results>\n";
return;
}
foreach(keys %$ref) {
my $lines = $ref->{$_};
my $length = @$lines;
printf "[%d %s] %s", $length, $_, @$lines[0];
}
}
sub cache_path
{
my ($paths, $line) = @_;
my $index = index($line, ': ');
my $path = substr($line, 0, $index);
$index += 2; # skip ': '
add_to_cache($paths, $path, substr($line, $index));
}
sub cache_filename
{
my ($files, $line) = @_;
my $index = index($line, ': ');
my $path = substr($line, 0, $index);
my $filename = basename($path);
$index += 2; # skip ': '
add_to_cache($files, $filename, substr($line, $index));
}
sub add_to_cache
{
my ($cache, $key, $value) = @_;
if (!$cache->{$key}) {
$cache->{$key} = ();
}
push @{$cache->{$key}}, $value;
}
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