CVSS 5.5 · Medium EPSS 0,21%
Kerentanan NULL Pointer Dereference pada linux kernel. Skor CVSS 3.1 5.5 (Medium) menurut NVD.
In the Linux kernel, the following vulnerability has been resolved: tracing: Fix bad hist from corrupting named_triggers list The following commands causes a crash: ~# cd /sys/kernel/tracing/events/rcu/rcu_callback ~# echo 'hist:name=bad:keys=common_pid:onmax(bogus).save(common_pid)' > trigger bash: echo: write error: Invalid argument ~# echo 'hist:name=bad:keys=common_pid' > trigger Because the following occurs: event_trigger_write() { trigger_process_regex() { event_hist_trigger_parse() { data = event_trigger_alloc(..); event_trigger_register(.., data) { cmd_ops->reg(.., data, ..) [hist_register_trigger()] { data->ops->init() [event_hist_trigger_init()] { save_named_trigger(name, data) { list_add(&data->named_list, &named_triggers); } } } } ret = create_actions(); (return -EINVAL) if (ret) goto out_unreg; [..] ret = hist_trigger_enable(data, ...) { list_add_tail_rcu(&data->list, &file->triggers); <<<---- SKIPPED!!! (this is important!) [..] out_unreg: event_hist_unregister(.., data) { cmd_ops->unreg(.., data, ..) [hist_unregister_trigger()] { list_for_each_entry(iter, &file->triggers, list) { if (!hist_trigger_match(data, iter, named_data, false)) <- never matches continue; [..] test = iter; } if (test && test->ops->free) <<<-- test is NULL test->ops->free(test) [event_hist_trigger_free()] { [..] if (data->name) del_named_trigger(data) { list_del(&data->named_list); <<<<-- NEVER gets removed! } } } } [..] kfree(data); <<<-- frees item but it is still on list The next time a hist with name is registered, it causes an u-a-f bug and the kernel can crash. Move the code around such that if event_trigger_register() succeeds, the next thing called is hist_trigger_enable() which adds it to the list. A bunch of actions is called if get_named_trigger_data() returns false. But that doesn't need to be called after event_trigger_register(), so it can be moved up, allowing event_trigger_register() to be called just before hist_trigger_enable() keeping them together and allowing the file->triggers to be properly populated.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
· uraikan di kalkulator | Vendor | Produk | Versi terdampak |
|---|---|---|
| linux | linux kernel | Versi 4.17 hingga sebelum 6.1.130 |
| linux | linux kernel | Versi 6.2 hingga sebelum 6.6.81 |
| linux | linux kernel | Versi 6.7 hingga sebelum 6.12.18 |
| linux | linux kernel | Versi 6.13 hingga sebelum 6.13.6 |
| linux | linux kernel | Versi 6.14 rc1 |
| linux | linux kernel | Versi 6.14 rc2 |
| linux | linux kernel | Versi 6.14 rc3 |
| linux | linux kernel | Versi 6.14 rc4 |