In the Linux kernel, the following vulnerability has been resolved:
mm/page_alloc: don't spin_trylock() in NMI on UP
Patch series "mm/page_alloc: fixes for free_pages_nolock() on RT/UP". Pre-existing bugs found by Sashiko during review of this other series:
https://lore.kernel.org/all/20260703-alloc-trylock-v5-0-c87b714e19d3@google.com/
I have not reproduced these bugs, and I suspect there is no real-world
user that is affected by them. This patch (of 2):
As noted in can_spin_trylock(), using this is unsafe in this context.
commit 620b46ed6ae17 ("mm/page_alloc: return NULL early from
alloc_frozen_pages_nolock() in NMI on UP") fixed this on the alloc side
but missed the free side.
Impact: If BPF programs using these features in NMI (probably tracing) are present on non-SMP builds this might crash the kernel and is probably exploitable by local attackers for privilege escalation.
Attack Parameters
Impact Assessment
CVSS Vector v3.1
Vulnerable Products 3
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Linux Linux_Kernel
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
|
6.15
|
6.18.51
|
|
Linux Linux_Kernel
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
|
6.15
|
7.2.5
|
|
Linux Linux_Kernel
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
|
6.15
|
7.3-rc1
|