On Fri, 2018-10-12 at 22:01 +0000, Edgecombe, Rick P wrote: > On Fri, 2018-10-12 at 16:32 +0200, Jessica Yu wrote: > > +++ Dave Hansen [11/10/18 16:47 -0700]: > > > On 10/11/2018 04:31 PM, Rick Edgecombe wrote: > > > > + if (check_inc_mod_rlimit(size)) > > > > + return NULL; > > > > + > > > > p = __vmalloc_node_range(size, MODULE_ALIGN, module_alloc_base, > > > > module_alloc_base + MODULES_VSIZE, > > > > gfp_mask, PAGE_KERNEL_EXEC, 0, > > > > @@ -65,6 +68,8 @@ void *module_alloc(unsigned long size) > > > > return NULL; > > > > } > > > > > > > > + update_mod_rlimit(p, size); > > > > > > Is there a reason we couldn't just rename all of the existing per-arch > > > module_alloc() calls to be called, say, "arch_module_alloc()", then put > > > this new rlimit code in a generic helper that does: > > > > > > > > > if (check_inc_mod_rlimit(size)) > > > return NULL; > > > > > > p = arch_module_alloc(...); > > > > > > ... > > > > > > update_mod_rlimit(p, size); > > > > > > > I second this suggestion. Just make module_{alloc,memfree} generic, > > non-weak functions that call the rlimit helpers in addition to the > > arch-specific arch_module_{alloc,memfree} functions. > > > > Jessica > > Ok, thanks. I am going to try another version of this with just a system wide > BPF JIT limit based on the problems Jann brought up. I think it would be nice > to > have a module space limit, but as far as I know the only way today un- > privlidged > users could fill the space is from BPF JIT. Unless you see another purpose > long > term? Err, nevermind. Going to try to include both limits. I'll incorporate this refactor into the next version.