On 07/03/2018 09:43 PM, Chris von Recklinghausen wrote:
Subject: [PATCH v7] add param that allows bootline control of hardened
usercopy
s/bootline/boot time/ ?
> v1->v2:
> remove CONFIG_HUC_DEFAULT_OFF
> default is now enabled, boot param disables
> move check to __check_object_size so as to not break optimization of
> __builtin_constant_p()
Sorry for late and drive-by suggestion, but I think the change above is
kind of a waste because there's a function call overhead only to return
immediately.
Something like this should work and keep benefits of both the built-in
check and avoiding function call?
static __always_inline void check_object_size(const void *ptr, unsigned
long n, bool to_user)
{
if (!__builtin_constant_p(n) &&
static_branch_likely(&bypass_usercopy_checks))
__check_object_size(ptr, n, to_user);
}
