[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <3047d23aacd2b058c5f6c40cd45f8511@smtp.hushmail.com>
Date: Tue, 16 Apr 2013 20:06:23 +0200
From: magnum <john.magnum@...hmail.com>
To: john-dev@...ts.openwall.com
Subject: Re: Segfaults probably caused by DEBUG code in memory.c (was: Segfault for linux-x86-native with -DDEBUG added)
Fix is committed now. I also fixed the bug below. This one actually exist in core too, although I'm not sure any core format uses mem_alloc_tiny() for SSE2 buffers.
#if ARCH_ALLOWS_UNALIGNED
- if (mem_saving_level > 2)
+ if (mem_saving_level > 2 && align != MEM_ALIGN_SIMD)
align = MEM_ALIGN_NONE;
#endif
magnum
On 16 Apr, 2013, at 19:40 , magnum <john.magnum@...hmail.com> wrote:
> Yeah, this is it. My bad. The rationale was to make memory debugging a lot easier under -DDEBUG but it was really *supposed* to still maintain requested alignment. Sometimes I amaze myself :-(
>
> magnum
>
>
> On 16 Apr, 2013, at 18:34 , jfoug <jfoug@....net> wrote:
>
>> From: Frank Dittrich [mailto:frank_dittrich@...mail.com]
>>>
>>> No segfaults.
>>> So I guess the -DDEBUG code in memory.c causes memory locations to be not aligned as expected.
>>
>> void *mem_alloc_tiny(size_t size, size_t align)
>> {
>> #ifdef DEBUG
>> void *res;
>>
>> +++ res = mem_alloc(size);
>> add_memory_link(res);
>> return res;
>> #else
>>
>> The line with +++. There is there assurance of alignment? Or do we need to allocate size+align, use that pointer in the add_memory_link, and then 'fix' the pointer?
>>
>>
>> void *mem_alloc_tiny(size_t size, size_t align)
>> {
>> #ifdef DEBUG
>> void *res;
>>
>> res = mem_alloc(size+align);
>> add_memory_link(res);
>> res += (align-1);
>> res -= (size_t)(res & (align-1));
>> return res;
>> #else
>>
>> Look at the bottom of the mem_alloc_tiny. IT does not use the return from mem_alloc (which is return from malloc), but fixes it up.
>>
>> p = mem_alloc(size + mask);
>> add_memory_link((void*)p);
>> p += mask;
>> p -= (size_t)p & mask;
>> return p;
>>
>>
>
>
>
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
