Re: [PATCH v2 1/2] x86/fpu: Fix memory leak with dynamic fpstate and exec()

["Chang S. Bae" <chang.seok.bae@intel.com>]

On 10/14/2026 5:19 PM, Chang S. Bae wrote:
> On 10/7/2026 10:59 PM, Guixiong Wei wrote:
>>
>> -void fpstate_free(struct fpu *fpu)
>> +void fpstate_free(struct fpstate *fpstate)
>>   {
>> -    if (fpu->fpstate && fpu->fpstate != &fpu->__fpstate)
>> -        vfree(fpu->fpstate);
>> +    if (fpstate && fpstate->is_valloc)
>> +        vfree(fpstate);
>>   }
> 
> Shouldn't is_valloc be cleared here, or when fpstate_reset() replaces 
> fpu->fpstate with the embedded fpstate?

No, is_valloc is pat of the vmalloc'ed memory itself.

That said, removing the original check does not seem reassuring either. 
Maybe, another option would be adding an internal helper:

   void __fpstate_reset(struct fpstate *fpstate)
   {
       if (fpstate && fpstate->is_valloc)
           vfree(fpstate);
   }

Then, refactor fpstate_realloc() and replace the vfree() in 
fpstate_free() with it, keeping the fpstate_free() prototype unchanged.

Thanks,
Chang