Re: [PATCH] leaking_addresses: add support for 32-bit kernel addresses

From: Kaiwan N Billimoria
Date: Mon Dec 04 2017 - 09:09:25 EST


Sure, thanks Alexander..
Tobin, request you to pl make the change while merging, thanks..


Thanks & Regards,
Kaiwan.


On Mon, Dec 4, 2017 at 6:07 PM, Alexander Kapshuk
<alexander.kapshuk@xxxxxxxxx> wrote:
> On Mon, Dec 4, 2017 at 12:20 PM, <kaiwan.billimoria@xxxxxxxxx> wrote:
>> On Mon, 2017-12-04 at 19:21 +1100, Tobin C. Harding wrote:
>>> On Mon, Dec 04, 2017 at 10:51:53AM +0530, Kaiwan N Billimoria wrote:
>>> > > ---
>>> > diff --git a/scripts/leaking_addresses.pl b/scripts/leaking_addresses.pl
>>> > index 9906dcf8b807..260b52e456f1 100755
>>> > --- a/scripts/leaking_addresses.pl
>>> > +++ b/scripts/leaking_addresses.pl
>>> > @@ -266,7 +266,7 @@ sub is_false_positive
>>> > sub is_false_positive_ix86_32
>>> > {
>>> > my ($match) = @_;
>>> > - state $page_offset = eval get_page_offset(); # only gets called once
>>> > + state $page_offset = hex get_page_offset(); # only gets called once
>>>
>>> I don't think this is valid ;) I meant use hex() to convert the string
>>> to an int so it doesn't throw the warning (inside get_page_offset()).
>>
>> Yup, got it, thanks :-p
>> Combined patch below:
>>
>>
>> ---
>> scripts/leaking_addresses.pl | 13 ++++++-------
>> 1 file changed, 6 insertions(+), 7 deletions(-)
>>
>> diff --git a/scripts/leaking_addresses.pl b/scripts/leaking_addresses.pl
>> index 9906dcf8b807..a595a2c66b12 100755
>> --- a/scripts/leaking_addresses.pl
>> +++ b/scripts/leaking_addresses.pl
>> @@ -266,8 +266,7 @@ sub is_false_positive
>> sub is_false_positive_ix86_32
>> {
>> my ($match) = @_;
>> - state $page_offset = eval get_page_offset(); # only gets called once
>> -
>> + state $page_offset = get_page_offset(); # only gets called once
>> if ($match =~ '\b(0x)?(f|F){8}\b') {
>> return 1;
>> }
>> @@ -283,7 +282,7 @@ sub is_false_positive_ix86_32
>> sub get_page_offset
>> {
>> my $page_offset;
>> - my $default_offset = "0xc0000000";
>> + my $default_offset = hex("0xc0000000");
>> my @config_files;
>>
>> # Allow --page-offset-32bit to override.
>> @@ -306,23 +305,23 @@ sub get_page_offset
>> } else {
>> $page_offset = parse_kernel_config_file($tmp_file);
>> if ($page_offset ne "") {
>> - return $page_offset;
>> + return hex($page_offset);
>> }
>> }
>> system("rm -f $tmp_file");
>> }
>>
>> foreach my $config_file (@config_files) {
>> - $config_file =~ s/\R*//g;
>> + chomp $config_file;
>> $page_offset = parse_kernel_config_file($config_file);
>> if ($page_offset ne "") {
>> - return $page_offset;
>> + return hex($page_offset);
>> }
>> }
>>
>> printf STDERR "\nFailed to parse kernel config files\n";
>> printf STDERR "*** NOTE ***\n";
>> - printf STDERR "Falling back to PAGE_OFFSET = %s\n\n", $default_offset;
>> + printf STDERR "Falling back to PAGE_OFFSET = 0x%x\n\n", $default_offset;
>
> Better use the '#' flag with the 'x' conversion specifier:
> perl -e 'my $default_offset = hex("0xc0000000");printf "%#x\n", $default_offset'
> 0xc0000000
>
>>
>> return $default_offset;
>> }
>> --
>> 2.14.3
>>
>> Thanks,
>> Kaiwan.
>>
>>> thanks,
>>> Tobin.