Inline Macro issue

[Mandeep Sandhu]

On Mon, Jul 15, 2013 at 6:03 PM, Saket Sinha <saket.sinha89 at gmail.com>wrote:

> Mandeep:
>
> Even this hasnt helped..though it was a btight idea. :(
>

And what _exact_ error does the compiler give if you use the new (modified)
macro?

The re-def error should not be there as the variable "new1" is within the
local scope now.

-mandeep



>
>
> P.S.-I can give my system on remote via Team Viewer, if you want to try.
>
> Regards,
> Saket Sinha
>
>
> On Mon, Jul 15, 2013 at 5:39 PM, Mandeep Sandhu <
> mandeepsandhu.chd at gmail.com> wrote:
>
>> How about:
>>
>> #define push_root() \
>> 	recursive_mutex_lock(&context->id_lock);	\
>> 	context->uid = current->fsuid;			\
>> 	context->gid = current->fsgid;			\
>>         do {                                            \
>>             struct cred *new1 = prepare_creds();           \
>>
>> //make changes to any member of this structure \
>>
>>             commit_creds(new1);                            \
>>         } while(0);
>>
>> HTH,
>>
>> -mandeep
>>
>>
>>
>>
>> On Mon, Jul 15, 2013 at 5:27 PM, Saket Sinha <saket.sinha89 at gmail.com>wrote:
>>
>>> Here is the macro
>>>
>>> https://github.com/HeisSpiter/hepunion/blob/master/fs/hepunion/hepunion.h#L393
>>>
>>> Now this driver is at 2.6.18 kernel. I have to upgrade it to 3.8.3.
>>> As I have said
>>> "current" in kernel is a global macro, that always point to the "struct
>>> task_struct * " of the currently executing task (for details on
>>> task_struct, ref Robert Love, pg 24-27).
>>>
>>>
>>> https://github.com/HeisSpiter/hepunion/blob/master/fs/hepunion/hepunion.h#L397
>>>
>>> Now if you look at thse two lines-
>>>
>>> current->fsuid = 0; \
>>> current->fsgid = 0
>>>
>>> Now task struct does not contain fsuid and fsgid, instead you have
>>> struct cred containing fsuid and fsgid.
>>> http://lxr.free-electrons.com/source/include/linux/cred.h#L102
>>>
>>> So normal method is
>>> struct cred *new1;
>>> new1 =prepare_creds();
>>> //make changes to any member of this structure
>>> commit_creds(new1);
>>>
>>> Now this above action I need to perform through a macro, in order to
>>> bring minimal changes to the driver.
>>>
>>> Now, I have told everything. Can someone suggest something that might
>>> work.
>>>
>>> Regards,
>>> Saket Sinha
>>>
>>>
>>>
>>>
>>>
>>> On Mon, Jul 15, 2013 at 5:07 PM, Mandeep Sandhu <
>>> mandeepsandhu.chd at gmail.com> wrote:
>>>
>>>>
>>>> On Mon, Jul 15, 2013 at 4:50 PM, Saket Sinha <saket.sinha89 at gmail.com>wrote:
>>>>
>>>>> Mandip:
>>>>> Error is expected error or declaration at the end of input
>>>>>
>>>>
>>>> Without looking at the code, it's difficult to comment further.
>>>>
>>>> Can you attach a small compilable example which exhibits the error?
>>>>
>>>> -mandeep
>>>>
>>>>
>>>>
>>>>>  Anish:
>>>>> that '\' should not be there first of all and even if I put it same
>>>>> error
>>>>>
>>>>>
>>>>
>>>
>>
>
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