CVE-2024-49856
Description
In the Linux kernel, the following vulnerability has been resolved: x86/sgx: Fix deadlock in SGX NUMA node search When the current node doesn't have an EPC section configured by firmware and all other EPC sections are used up, CPU can get stuck inside the while loop that looks for an available EPC page from remote nodes indefinitely, leading to a soft lockup. Note how nid_of_current will never be equal to nid in that while loop because nid_of_current is not set in sgx_numa_mask. Also worth mentioning is that it's perfectly fine for the firmware not to setup an EPC section on a node. While setting up an EPC section on each node can enhance performance, it is not a requirement for functionality. Rework the loop to start and end on *a* node that has SGX memory. This avoids the deadlock looking for the current SGX-lacking node to show up in the loop when it never will.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2024-49856
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2024-49856.html
Vendor advisory: redhat — https://access.redhat.com/errata/RHSA-2025:6966
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rhel | 9 | fixed | |
| sles | affected | | |
| debian | bookworm | fixed | 6.1.115-1 |
| debian | bullseye | fixed | 0 |
| debian | forky | fixed | 6.11.2-1 |
| debian | sid | fixed | 6.11.2-1 |
| debian | trixie | fixed | 6.11.2-1 |
References
Verify integrity in audit chain (admin only). AS-IS.