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.
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
Debian | 12 | all | linux | < 6.1.90-1 | linux_6.1.90-1_all.deb |
Debian | 11 | all | linux | < 5.10.216-1 | linux_5.10.216-1_all.deb |
Debian | 10 | all | linux | <= 4.19.249-2 | linux_4.19.249-2_all.deb |
Debian | 999 | all | linux | < 6.8.9-1 | linux_6.8.9-1_all.deb |
Debian | 13 | all | linux | < 6.8.9-1 | linux_6.8.9-1_all.deb |