Merge tag 'iio-fixes-for-4.17a' of git://git.kernel.org/pub/scm/linux/kernel/git...

[linux.git] / scripts / leaking_addresses.pl

diff --git a/scripts/leaking_addresses.pl b/scripts/leaking_addresses.pl
index 6e5bc57caeaaf09373a479f2eaf3032e19ec61e2..6a897788f5a7ecd3eb699ebd6aec21ee1125aecd 100755 (executable)
--- a/scripts/leaking_addresses.pl
+++ b/scripts/leaking_addresses.pl
@@ -10,6 +10,14 @@
 # Use --debug to output path before parsing, this is useful to find files that
 # cause the script to choke.
 
+#
+# When the system is idle it is likely that most files under /proc/PID will be
+# identical for various processes.  Scanning _all_ the PIDs under /proc is
+# unnecessary and implies that we are thoroughly scanning /proc.  This is _not_
+# the case because there may be ways userspace can trigger creation of /proc
+# files that leak addresses but were not present during a scan.  For these two
+# reasons we exclude all PID directories under /proc except '1/'
+
 use warnings;
 use strict;
 use POSIX;
@@ -23,7 +31,6 @@ use bigint qw/hex/;
 use feature 'state';
 
 my $P = $0;
-my $V = '0.01';
 
 # Directories to scan.
 my @DIRS = ('/proc', '/sys');
@@ -52,6 +59,7 @@ my $page_offset_32bit = 0;    # Page offset for 32-bit kernel.
 my @skip_abs = (
        '/proc/kmsg',
        '/proc/device-tree',
+       '/proc/1/syscall',
        '/sys/firmware/devicetree',
        '/sys/kernel/debug/tracing/trace_pipe',
        '/sys/kernel/security/apparmor/revision');
@@ -76,7 +84,6 @@ sub help
        print << "EOM";
 
 Usage: $P [OPTIONS]
-Version: $V
 
 Options:
 
@@ -356,7 +363,7 @@ sub may_leak_address
        }
 
        $address_re = get_address_re();
-       while (/($address_re)/g) {
+       while ($line =~ /($address_re)/g) {
                if (!is_false_positive($1)) {
                        return 1;
                }
@@ -456,6 +463,16 @@ sub parse_file
        close $fh;
 }
 
+# Checks if the actual path name is leaking a kernel address.
+sub check_path_for_leaks
+{
+       my ($path) = @_;
+
+       if (may_leak_address($path)) {
+               printf("Path name may contain address: $path\n");
+       }
+}
+
 # Recursively walk directory tree.
 sub walk
 {
@@ -472,8 +489,14 @@ sub walk
                        my $path = "$pwd/$file";
                        next if (-l $path);
 
+                       # skip /proc/PID except /proc/1
+                       next if (($path =~ /^\/proc\/[0-9]+$/) &&
+                                ($path !~ /^\/proc\/1$/));
+
                        next if (skip($path));
 
+                       check_path_for_leaks($path);
+
                        if (-d $path) {
                                push @dirs, $path;
                                next;