The commit 4982223e51e8 module: set nx before marking module MODULE_STATE_COMING. introduced a regression: if a module fails to parse its arguments or if mod_sysfs_setup fails, then the module's memory will be freed while still read-only. Anything that reuses that memory will crash as soon as it tries to write to it.
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| @@ -3304,6 +3304,11 @@ static int load_module(struct load_info *info, const char __user *uargs, · 3303 unmodified lines | |||
| 3304 | mutex_lock(&module_mutex); | 3304 | mutex_lock(&module_mutex); |
| 3305 | module_bug_cleanup(mod); | 3305 | module_bug_cleanup(mod); |
| 3306 | mutex_unlock(&module_mutex); | 3306 | mutex_unlock(&module_mutex); |
| 3307 | |||
| 3308 | /* we can't deallocate the module until we clear memory protection */ | ||
| 3309 | unset_module_init_ro_nx(mod); | ||
| 3310 | unset_module_core_ro_nx(mod); | ||
| 3311 | |||
| 3307 | ddebug_cleanup: | 3312 | ddebug_cleanup: |
| 3308 | dynamic_debug_remove(info->debug); | 3313 | dynamic_debug_remove(info->debug); |
| 3309 | synchronize_sched(); | 3314 | synchronize_sched(); |