On Mon 2022-10-10 15:12 +0000, Elliott, Robert (Servers) wrote:
> When repeatedly using the tcrypt module (which is designed to never
> load successfully), the "Unloaded tainted modules" list grows forever:
>
> Unloaded tainted modules: tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1
> tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1
> tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1
> tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1
> tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1
> tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1
> tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1
> tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1 tcrypt():1
> tcrypt():1 tcrypt():1 padlock_aes():1 padlock_aes():1
> isst_if_mbox_msr():1 acpi_cpufreq():1 pcc_cpufreq():1 isst_if_mbox_msr():1
> acpi_cpufreq():1 pcc_cpufreq():1 acpi_cpufreq():1 acpi_cpufreq():1
> pcc_cpufreq():1 isst_if_mbox_msr():1 acpi_cpufreq():1 acpi_cpufreq():1
> pcc_cpufreq():1 isst_if_mbox_msr():1 acpi_cpufreq():1 acpi_cpufreq():1
> isst_if_mbox_msr():1 isst_if_mbox_msr():1
> acpi_cpufreq():1 pcc_cpufreq():1 acpi_cpufreq():1 isst_if_mbox_msr():1
>
> Some other modules like acpi_cpufreq() are repeated too.
>
> Maybe this check after the name comparison:
> mod_taint->taints & mod->taints
> should be:
> mod_taint->taints == mod->taints
>
> or shouldn't be there at all?
>
Hi Elliot,
Sorry about that.
This is already addressed in linux-next:
commit a0830747f4e6810876e5f5329ce941e258e13a22
Author: Aaron Tomlin <atomlin@xxxxxxxxxx>
Date: Fri Oct 7 14:32:44 2022 +0100
module: tracking: Keep a record of tainted unloaded modules only
This patch ensures that no module record/or entry is added to the
unloaded_tainted_modules list if it does not carry a taint.
Reported-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Fixes: 99bd9956551b ("module: Introduce module unload taint tracking")
Signed-off-by: Aaron Tomlin <atomlin@xxxxxxxxxx>
diff --git a/kernel/module/tracking.c b/kernel/module/tracking.c
index a139e63b6f20..26d812e07615 100644
--- a/kernel/module/tracking.c
+++ b/kernel/module/tracking.c
@@ -22,6 +22,9 @@ int try_add_tainted_module(struct module *mod)
module_assert_mutex_or_preempt();
+ if (!mod->taints)
+ goto out;
+
list_for_each_entry_rcu(mod_taint, &unloaded_tainted_modules, list,
lockdep_is_held(&module_mutex)) {
if (!strcmp(mod_taint->name, mod->name) &&
Kind regards,
--
Aaron Tomlin
