CVEvulnerability
CVE-2026-93172
- Status
- Received
- Published
- 2026-09-17
- Last modified
- 2026-10-21
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
mm/mm_init: handle alloc_percpu failure in free_area_init_core_hotplug
We miss a failed allocation check for pgdat->per_cpu_nodestats, which
results in a NULL deref when we offset into the per-cpu area.
Propagate -ENOMEM up the stack and leave per_cpu_nodestats pointing
at boot_nodestats so a later online can retry the allocation.
hotadd_init_pgdat() returns NULL on failure, which __try_online_node()
already maps to -ENOMEM.
On failure nothing needs to be unwound:
- the node is never marked online
- per_cpu_nodestats is left pointing at boot_nodestats
- __add_memory_resource() cleans up pending memblock resources
- later online attempts retry the per_cpu_nodestats allocation
References
- https://git.kernel.org/stable/c/1017fe1c7f48e511c5a680e3057005daaff2f3a2 git.kernel.org
- https://git.kernel.org/stable/c/2ebce860bdd7ae5e13002811bc9bbbf33fcfc221 git.kernel.org
- https://git.kernel.org/stable/c/4cc5caef9a8d1894dfa31d84a0daa0ac1437dadc git.kernel.org
- https://git.kernel.org/stable/c/4dda09e7ca0bf0c3fa7c5c8f134d9804b67f455c git.kernel.org
- https://git.kernel.org/stable/c/bc3b5e6519b8df22d622a03eab6772784da97db4 git.kernel.org