On Mon, 15 Apr 2019, Josh Poimboeuf wrote: > On Mon, Apr 15, 2019 at 06:07:44PM +0200, Thomas Gleixner wrote: > > > > > > Looks like stack_trace.nr_entries isn't initialized? (though this code > > > gets eventually replaced by a later patch) > > > > struct initializer initialized the non mentioned fields to 0, if I'm not > > totally mistaken. > > Hm, it seems you are correct. And I thought I knew C. :) > > > Who actually reads this stack trace? I couldn't find a consumer. > > > > It's stored directly in the memory pointed to by @addr and that's the freed > > cache memory. If that is used later (UAF) then the stack trace can be > > printed to see where it was freed. > > Right... but who reads it? Indeed. I didn't check but I know that I saw that info printed at least a decade ago. Looks like that debug magic in slab.c has seen major changes since then. Thanks, tglx
