On Tue, Aug 28, 2018 at 1:33 PM Andrey Ryabinin <[email protected]> wrote: > On 08/28/2018 01:38 PM, Jann Horn wrote: > >> Why this has to be done in the rewind_stack_do_exit()? > >> Are there any problems with calling the kasan_unpoison_task_stack(current) > >> from oops_end(), before the rewind_stack_do_exit()? > > > > Ooh, good point! I didn't see that KASAN instrumentation is disabled > > for dumpstack.c. > > It doesn't really matter. This would work with instrumented oops_end() as > well. > kasan_unpoison_task_stack() will unpoison everything including oops_end's > stack. > It would be also ok if kasan_unpoison_task_stack() instrumented,
But then that would rely on ASAN implementation details, so I'd be hesitant to do that. > or calling any number of instrumented functions > in between kasan_unpoison_task_stack() and rewind_stack_do_exit(). As long as > we return from these functions before > the rewind_stack_do_exit(), the stack will be unpoisoned on return. Yeah, I understand that. :)
