CVE-2024-49856
x86/sgx: Fix deadlock in SGX NUMA node search
Vexday Risk Score
3Low
SSVC decision (CISA)
Track
No exploitation signal → monitor
CVSS —EPSS 0.2%KEV nãoPoC —Nuclei —Metasploit —Patch —
Lifecycle
21 Oct 2024Published on NVD
Recommendation: Monitor — no exploitation signal at the moment.
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.
Affected products
Linux · LinuxReferences
https://git.kernel.org/stable/c/0f89fb4042c08fd143bfc28af08bf6c8a0197eeahttps://git.kernel.org/stable/c/20c96d0aaabfe361fc2a11c173968dc67feadbbfhttps://git.kernel.org/stable/c/40fb64257dab507d86b5f1f2a62f3669ef0c91a8https://git.kernel.org/stable/c/8132510c915815e6b537ab937d94ed66893bc7b8https://git.kernel.org/stable/c/9c936844010466535bd46ea4ce4656ef17653644https://git.kernel.org/stable/c/fb2d057539eda67ec7cfc369bf587e6518a9b99dhttps://lists.debian.org/debian-lts-announce/2025/01/msg00001.html