CVE-2024-57984

In the Linux kernel, the following vulnerability has been resolved:

i3c: dw: Fix use-after-free in dw_i3c_master driver due to race condition

In dw_i3c_common_probe, &master->hj_work is bound with dw_i3c_hj_work. And dw_i3c_master_irq_handler can call dw_i3c_master_irq_handle_ibis function to start the work.

If we remove the module which will call dw_i3c_common_remove to make cleanup, it will free master->base through i3c_master_unregister while the work mentioned above will be used. The sequence of operations that may lead to a UAF bug is as follows:

CPU0 CPU1

                                 | dw_i3c_hj_work

dw_i3c_common_remove | i3c_master_unregister(&master->base) | device_unregister(&master->dev) | device_release | //free master->base | | i3c_master_do_daa(&master->base) | //use master->base

Fix it by ensuring that the work is canceled before proceeding with the cleanup in dw_i3c_common_remove.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

Potential Mitigations

References

• https://git.kernel.org/stable/c/60d2fb033a999bb644f8e8606ff4a1b82de36c6f
• https://git.kernel.org/stable/c/9b0063098fcde17cd2894f2c96459b23388507ca
• https://git.kernel.org/stable/c/b75439c945b94dd8a2b645355bdb56f948052601
• https://git.kernel.org/stable/c/fc84dd3c909a372c0d130f5f84c404717c17eed8