[PATCH v2 3/3] module: Show the last unloaded module's taint flag(s)

From: Aaron Tomlin
Date: Thu Jul 14 2022 - 11:39:59 EST


For diagnostic purposes, this patch, in addition to keeping a record/or
track of the last known unloaded module, we now will include the
module's taint flag(s) too e.g: " [last unloaded: fpga_mgr_mod(OE)]"

Signed-off-by: Aaron Tomlin <atomlin@xxxxxxxxxx>
---
kernel/module/main.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/kernel/module/main.c b/kernel/module/main.c
index c5db13d06995..96ec7f94228d 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -524,7 +524,10 @@ static struct module_attribute modinfo_##field = { \
MODINFO_ATTR(version);
MODINFO_ATTR(srcversion);

-static char last_unloaded_module[MODULE_NAME_LEN+1];
+static struct {
+ char name[MODULE_NAME_LEN + 1];
+ char taints[MODULE_FLAGS_BUF_SIZE];
+} last_unloaded_module;

#ifdef CONFIG_MODULE_UNLOAD

@@ -694,6 +697,7 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
{
struct module *mod;
char name[MODULE_NAME_LEN];
+ char buf[MODULE_FLAGS_BUF_SIZE];
int ret, forced = 0;

if (!capable(CAP_SYS_MODULE) || modules_disabled)
@@ -753,8 +757,9 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,

async_synchronize_full();

- /* Store the name of the last unloaded module for diagnostic purposes */
- strscpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
+ /* Store the name and taints of the last unloaded module for diagnostic purposes */
+ strscpy(last_unloaded_module.name, mod->name, sizeof(last_unloaded_module.name));
+ strscpy(last_unloaded_module.taints, module_flags(mod, buf, false), sizeof(last_unloaded_module.taints));

free_module(mod);
/* someone could wait for the module in add_unformed_module() */
@@ -3128,7 +3133,8 @@ void print_modules(void)

print_unloaded_tainted_modules();
preempt_enable();
- if (last_unloaded_module[0])
- pr_cont(" [last unloaded: %s]", last_unloaded_module);
+ if (last_unloaded_module.name[0])
+ pr_cont(" [last unloaded: %s%s]", last_unloaded_module.name,
+ last_unloaded_module.taints);
pr_cont("\n");
}
--
2.34.3