Function bprm_creds_for_exec 

pub fn bprm_creds_for_exec(
    current_task: &CurrentTask,
    executable: &NamespaceNode,
    elf_state: &mut ResolvedElf,
) -> Result<(), Errno>

Checks if exec is allowed and if so, checks permissions related to the transition (if any) from the pre-exec security context to the post-exec context. Updates the Credentials in the elf_state with the appropriate security state.

Corresponds to the bprm_creds_for_exec() LSM hook.