blob: 1fa1cf3158514ea2b1aa271cfd544d5515c3f6f5 [file] [log] [blame]
#!/usr/bin/perl
# Check for malloc calls not shortly followed by initialisation.
#
# Known limitations:
# - false negative: can't see allocations spanning more than one line
# - possible false negatives, see patterns
# - false positive: malloc-malloc-init-init is not accepted
# - false positives: "non-standard" init functions (eg, the things being
# initialised is not the first arg, or initialise struct members)
#
# Since false positives are expected, the results must be manually reviewed.
#
# Typical usage: scripts/malloc-init.pl library/*.c
use warnings;
use strict;
use utf8;
use open qw(:std utf8);
my $limit = 7;
my $inits = qr/memset|memcpy|_init|fread|base64_..code/;
# cases to bear in mind:
#
# 0. foo = malloc(...); memset( foo, ... );
# 1. *foo = malloc(...); memset( *foo, ... );
# 2. type *foo = malloc(...); memset( foo, ...);
# 3. foo = malloc(...); foo_init( (type *) foo );
# 4. foo = malloc(...); for(i=0..n) { init( &foo[i] ); }
#
# The chosen patterns are a bit relaxed, but unlikely to cause false positives
# in real code (initialising *foo or &foo instead of foo will likely be caught
# by functional tests).
#
my $id = qr/([a-zA-Z-0-9_\->\.]*)/;
my $prefix = qr/\s(?:\*?|\&?|\([a-z_]* \*\))\s*/;
my $name;
my $line;
my @bad;
die "Usage: $0 file.c [...]\n" unless @ARGV;
while (my $file = shift @ARGV)
{
open my $fh, "<", $file or die "read $file failed: $!\n";
while (<$fh>)
{
if( /polarssl_malloc\(/ ) {
if( /$id\s*=.*polarssl_malloc\(/ ) {
push @bad, "$file:$line:$name" if $name;
$name = $1;
$line = $.;
} else {
push @bad, "$file:$.:???" unless /return polarssl_malloc/;
}
} elsif( $name && /(?:$inits)\($prefix\Q$name\E\b/ ) {
undef $name;
} elsif( $name && $. - $line > $limit ) {
push @bad, "$file:$line:$name";
undef $name;
undef $line;
}
}
close $fh or die;
}
print "$_\n" for @bad;