On Tue, 2023-02-21 at 09:31 +0100, David Hildenbrand wrote: > > > Why not modify is_stack_mapping() ? > > > > It kind of sticks out a little in this conditional, but > > is_stack_mapping() has this comment: > > /* > > * Stack area - automatically grows in one direction > > * > > * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous: > > * do_mmap() forbids all other combinations. > > */ > > > > Shadow stack don't grow, so it doesn't quite fit. There used to be > > an > > is_shadow_stack_mapping(), but it was removed because all that was > > needed (for the time being) was the simple bitwise AND: > > > > https://lore.kernel.org/lkml/804adbac-61e6-0fd2-f726-5735fb290199@xxxxxxxxx/ > > As there is only a single user of is_stack_mapping(), I'd simply > have > adjusted the doc of is_stack_mapping() to include shadow stacks. Ok, I'll update the comment and add it there.
