linux-kernel - Re: [Part1 PATCH v4 10/17] x86/mm, resource: Use PAGE_KERNEL protection for ioremap of memory pages

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Tue, 26 Sep 2017 14:11:42 -0500
From:   Brijesh Singh <brijesh.singh@....com>
To:     Borislav Petkov <bp@...e.de>
Cc:     brijesh.singh@....com, linux-kernel@...r.kernel.org,
        x86@...nel.org, kvm@...r.kernel.org,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H . Peter Anvin" <hpa@...or.com>,
        Andy Lutomirski <luto@...nel.org>,
        Tom Lendacky <thomas.lendacky@....com>,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Laura Abbott <labbott@...hat.com>,
        Jérôme Glisse <jglisse@...hat.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Dan Williams <dan.j.williams@...el.com>,
        Kees Cook <keescook@...omium.org>
Subject: Re: [Part1 PATCH v4 10/17] x86/mm, resource: Use PAGE_KERNEL
 protection for ioremap of memory pages



On 09/17/2017 09:07 AM, Borislav Petkov wrote:

...

>> -static int __ioremap_check_ram(unsigned long start_pfn, unsigned long nr_pages,
>> -			       void *arg)
>> +static int __ioremap_check_ram(struct resource *res)
>>   {
>> +	unsigned long start_pfn, stop_pfn;
>>   	unsigned long i;
>>   
>> -	for (i = 0; i < nr_pages; ++i)
>> -		if (pfn_valid(start_pfn + i) &&
>> -		    !PageReserved(pfn_to_page(start_pfn + i)))
>> -			return 1;
>> +	if ((res->flags & IORESOURCE_SYSTEM_RAM) != IORESOURCE_SYSTEM_RAM)
>> +		return 0;
>> +
>> +	start_pfn = (res->start + PAGE_SIZE - 1) >> PAGE_SHIFT;
>> +	stop_pfn = (res->end + 1) >> PAGE_SHIFT;
>> +	if (stop_pfn > start_pfn) {
>> +		for (i = 0; i < (stop_pfn - start_pfn); ++i)
>> +			if (pfn_valid(start_pfn + i) &&
>> +			    !PageReserved(pfn_to_page(start_pfn + i)))
>> +				return 1;
>> +	}
>>   
>>   	return 0;
> 
> Should return bool I guess.
> 

Yes, I will fix it in next rev. thanks

thanks