CVE-2024-46689

Summary

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

soc: qcom: cmd-db: Map shared memory as WC, not WB

Linux does not write into cmd-db region. This region of memory is write protected by XPU. XPU may sometime falsely detect clean cache eviction as "write" into the write protected region leading to secure interrupt which causes an endless loop somewhere in Trust Zone.

The only reason it is working right now is because Qualcomm Hypervisor maps the same region as Non-Cacheable memory in Stage 2 translation tables. The issue manifests if we want to use another hypervisor (like Xen or KVM), which does not know anything about those specific mappings.

Changing the mapping of cmd-db memory from MEMREMAP_WB to MEMREMAP_WT/WC removes dependency on correct mappings in Stage 2 tables. This patch fixes the issue by updating the mapping to MEMREMAP_WC.

I tested this on SA8155P with Xen.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux312416d9171a1460b7ed8d182b5b540c910ce80d < 0ee9594c974368a17e85a431e9fe1c14fb65c278affected
LinuxLinux312416d9171a1460b7ed8d182b5b540c910ce80d < f5a5a5a0e95f36e2792d48e6e4b64e665eb01374affected
LinuxLinux312416d9171a1460b7ed8d182b5b540c910ce80d < eaff392c1e34fb77cc61505a31b0191e5e46e271affected
LinuxLinux312416d9171a1460b7ed8d182b5b540c910ce80d < d9d48d70e922b272875cda60d2ada89291c840cfaffected
LinuxLinux312416d9171a1460b7ed8d182b5b540c910ce80d < ef80520be0ff78ae5ed44cb6eee1525e65bebe70affected
LinuxLinux312416d9171a1460b7ed8d182b5b540c910ce80d < 62c2d63605ca25b5db78a347ed303c0a0a77d5b4affected
LinuxLinux312416d9171a1460b7ed8d182b5b540c910ce80d < f9bb896eab221618927ae6a2f1d566567999839daffected
LinuxLinux4.18affected
LinuxLinux0 < 4.18unaffected
LinuxLinux5.4.283 <= 5.4.*unaffected
LinuxLinux5.10.225 <= 5.10.*unaffected
LinuxLinux5.15.166 <= 5.15.*unaffected
LinuxLinux6.1.108 <= 6.1.*unaffected
LinuxLinux6.6.49 <= 6.6.*unaffected
LinuxLinux6.10.8 <= 6.10.*unaffected
LinuxLinux6.11 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

CVE Program Container

Additional References

References