On 07/10/2019 21.26, Thomas Meyer wrote: > commit b7b2562f7252 ("kernel/groups.c: use sort library function") > introduced the sort library function. > also use the bsearch library function instead of open-coding the binary > search.
Yes, but please note the difference between sorting the group_info and searching it: The former is done quite rarely - the setgroups syscall is used roughly once per login-session. But the searching of that structure is done more or less every time a user accesses a file not owned by that user (e.g., any time a normal user accesses anything in /usr) - at least if I'm reading acl_permission_check() right. So using a callback-based interface, especially in a post-spectre world, may have a somewhat large performance impact. Rasmus