发布于3月6日3月6日 Members Debian: CVE-2024-35955: linux -- security update Severity 4 CVSS (AV:L/AC:M/Au:N/C:P/I:P/A:P) Published 05/20/2024 Created 06/28/2024 Added 06/27/2024 Modified 07/03/2024 Description In the Linux kernel, the following vulnerability has been resolved: kprobes: Fix possible use-after-free issue on kprobe registration When unloading a module, its state is changing MODULE_STATE_LIVE -> MODULE_STATE_GOING -> MODULE_STATE_UNFORMED. Each change will take a time. `is_module_text_address()` and `__module_text_address()` works with MODULE_STATE_LIVE and MODULE_STATE_GOING. If we use `is_module_text_address()` and `__module_text_address()` separately, there is a chance that the first one is succeeded but the next one is failed because module->state becomes MODULE_STATE_UNFORMED between those operations. In `check_kprobe_address_safe()`, if the second `__module_text_address()` is failed, that is ignored because it expected a kernel_text address. But it may have failed simply because module->state has been changed to MODULE_STATE_UNFORMED. In this case, arm_kprobe() will try to modify non-exist module text address (use-after-free). To fix this problem, we should not use separated `is_module_text_address()` and `__module_text_address()`, but use only `__module_text_address()` once and do `try_module_get(module)` which is only available with MODULE_STATE_LIVE. Solution(s) debian-upgrade-linux References https://attackerkb.com/topics/cve-2024-35955 CVE - 2024-35955 DLA-3840-1 DLA-3842-1
