}
EXPORT_SYMBOL_GPL(find_symbol);
-/* Search for module by name: must hold module_mutex. */
+/*
+ * Search for module by name: must hold module_mutex (or preempt disabled
+ * for read-only access).
+ */
static struct module *find_module_all(const char *name, size_t len,
bool even_unformed)
{
struct module *mod;
- module_assert_mutex();
+ module_assert_mutex_or_preempt();
list_for_each_entry(mod, &modules, list) {
if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
struct module *find_module(const char *name)
{
+ module_assert_mutex();
return find_module_all(name, strlen(name), false);
}
EXPORT_SYMBOL_GPL(find_module);
if (core_kernel_text(a))
return;
- /* module_text_address is safe here: we're supposed to have reference
- * to module from symbol_get, so it can't go away. */
+ /*
+ * Even though we hold a reference on the module; we still need to
+ * disable preemption in order to safely traverse the data structure.
+ */
+ preempt_disable();
modaddr = __module_text_address(a);
BUG_ON(!modaddr);
module_put(modaddr);
+ preempt_enable();
}
EXPORT_SYMBOL_GPL(symbol_put_addr);