Re: [RFC PATCH v2 2/2] module: When modifying a module's text ignore modules which are going away too

From: Rusty Russell
Date: Fri Nov 18 2016 - 01:18:32 EST


Aaron Tomlin <atomlin@xxxxxxxxxx> writes:
> By default, during the access permission modification of a module's core
> and init pages, we only ignore modules that are malformed. Albeit for a
> module which is going away, it does not make sense to change its text to
> RO since the module should be RW, before deallocation.
>
> This patch makes set_all_modules_text_ro() skip modules which are going
> away too.
>
> Signed-off-by: Aaron Tomlin <atomlin@xxxxxxxxxx>

Acked-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>

Thanks!
Rusty.

> ---
> kernel/module.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/module.c b/kernel/module.c
> index ff93ab8..2a383df 100644
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -1969,7 +1969,8 @@ void set_all_modules_text_ro(void)
>
> mutex_lock(&module_mutex);
> list_for_each_entry_rcu(mod, &modules, list) {
> - if (mod->state == MODULE_STATE_UNFORMED)
> + if (mod->state == MODULE_STATE_UNFORMED ||
> + mod->state == MODULE_STATE_GOING)
> continue;
>
> frob_text(&mod->core_layout, set_memory_ro);
> --
> 2.5.5