Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: riscv: errata: select RISCV_ALTERNATIVE_EARLY for THEAD GHOSTWRITE errata_probe_ghostwrite() only marks the CPU as vulnerable when it is called at the RISCV_ALTERNATIVES_EARLY_BOOT stage, and the mitigation in ghostwrite_enable_mitigation() only takes effect if the vulnerable state was recorded before the boot alternatives are patched. The early boot stage is only executed when CONFIG_RISCV_ALTERNATIVE_EARLY is enabled, which currently is only selected by ERRATA_THEAD_MAE. In a kernel built with ERRATA_THEAD_GHOSTWRITE=y but ERRATA_THEAD_MAE=n, the early alternatives never run, so ghostwrite_state is never set to VULNERABLE: ghostwrite_enable_mitigation() returns false, xtheadvector remains enabled, and sysfs reports "Not affected" on a vulnerable T-Head C9xx CPU. Select RISCV_ALTERNATIVE_EARLY from ERRATA_THEAD_GHOSTWRITE so that the vulnerability is detected in the early boot stage and the default mitigation is applied.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 4bf97069239bcfca9840936313c7ac35a6e04488 before fa465a7819ecbe5801b78c088d3cadaf2664b8ca; affected 4bf97069239bcfca9840936313c7ac35a6e04488 before 7fee577a2fa78b9a76da015beec1ccf978746ebb; affected 4bf97069239bcfca9840936313c7ac35a6e04488 before 298510bbc7c3017c0faf481c6ea66f1065b657b4 |
| Linux / Linux | affected 6.14; unaffected 0 before 6.14; unaffected 6.18.57 through 6.18.*; unaffected 7.2.11 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.