In the Linux kernel, a vulnerability has been identified and resolved. In this post, we will discuss the details of the vulnerability, provide a code snippet, and link to original references. This vulnerability involves the missing loop break condition in pmdomain: imx8mp-blk-ctrl.

The Vulnerability

The vulnerability exists in the imx8mp_blk_ctrl_remove() function, where the loop continues until an out-of-bounds exception occurs. This can lead to potential security risks as well as unintended behavior. Below is the sample code snippet showcasing the issue:

pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
...
x10: ffffff80d05376c x9 : ffffffc0808ed2d8
...
Call trace:
 dev_pm_domain_detach+x8/x48
 platform_shutdown+x2c/x48
 device_shutdown+x158/x268
 kernel_restart_prepare+x40/x58
 kernel_kexec+x58/xe8
 __do_sys_reboot+x198/x258
 __arm64_sys_reboot+x2c/x40
 invoke_syscall+x5c/x138
 el_svc_common.constprop.+x48/xf
 do_el_svc+x24/x38
 el_svc+x38/xc8
 elt_64_sync_handler+x120/x130
 elt_64_sync+x190/x198
Code: 8128c2d ffffffc aa1e03e9 d503201f

As shown in the code snippet, the missing loop break condition leads to a chain of system calls that may result in system instability or even crashes.

The Resolution

The developers have resolved the vulnerability by adding the missing loop break condition, preventing the out-of-bounds exception from occurring.

- Linux Kernel Mailing List (LKML) discussion on the vulnerability
- Kernel.org commit that fixes the vulnerability

Conclusion

In this post, we discussed CVE-2025-21668, a vulnerability in the Linux kernel affecting the pmdomain: imx8mp-blk-ctrl. We provided a code snippet detailing the issue and links to relevant discussions and commits resolving the vulnerability. It is essential for developers and system administrators to keep their kernel up to date to protect against such vulnerabilities and ensure the stability and security of their systems.

Timeline

Published on: 01/31/2025 12:15:27 UTC