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Re: [PATCH 05/10] Implement protection of stack variables
Jakub Jelinek <jakub@redhat.com> writes:
> On Mon, Nov 12, 2012 at 12:30:37PM +0100, Dodji Seketeli wrote:
>> + For this function, the stack protected by asan will be organized as
>> + follows, from the top of the stack to the bottom:
>> +
>> + Slot 1/ [red zone of 32 bytes called 'RIGHT RedZone']
>> +
>> + Slot 2/ [24 bytes for variable 'a']
>> +
>> + Slot 3/ [8 bytes of red zone, that adds up to the space of 'a' to make
>> + the next slot be 32 bytes aligned; this one is called Partial
>> + Redzone; this 32 bytes alignment is an asan constraint]
>
> If you are going from top to bottom, the padding (here Slot 3/) goes above
> the variables, so you need to swap Slot 2/ and 3/, 5/ and 6/ and adjust
> comment for former slot 6/.
Done, committed to trunk.
>
>> +
>> + Slot 4/ [red zone of 32 bytes called 'Middle RedZone']
>> +
>> + Slot 5/ [8 bytes for variable 'b']
>> +
>> + Slot 6/ [24 bytes of Partial Red Zone (similar to slot 3]
>> +
>> + Slot 7/ [32 bytes of Red Zone at the bottom of the stack, called 'LEFT
>> + RedZone']
>> +
> ...
>> + The shadow memory for that stack layout is going to look like this:
>> +
>> + - content of shadow memory 8 bytes for slot 7: 0xFFFFFFFFF1F1F1F1.
>
> Please strip the extra leading FFFFFFFF from the constants, the stores are
> all 32-bit and the constants are just sign-extended.
Done, committed to trunk.
--
Dodji