Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
net/sched: cake: reject overhead values that underflow length
CAKE accepts signed overhead values and stores them in an s16, but the adjusted packet length calculation uses unsigned arithmetic. A negative effective length can therefore wrap to a large value.
Such configurations make rate accounting depend on integer wraparound rather than on the packet size userspace intended to model. A static netlink lower bound is not enough because packets reaching CAKE can be smaller than any reasonable manual-overhead allowance.
Fold the signed overhead adjustment into the existing datapath MPU clamp so negative adjusted lengths are clamped before link-layer framing adjustments.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 4.19.0 (+7 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Amazon Linux 2023 | Planned | — |
| Debian 13 | Released |
13 kernels
|
| Oracle Linux 8 UEK 7 | Released |
112 kernels
|
| Oracle Linux 9 UEK 7 | Released |
112 kernels
|
| Ubuntu 22.04 | Planned | — |
| Ubuntu 22.04 AWS | Planned | — |
| Ubuntu 22.04 Azure | Planned | — |
| Ubuntu 24.04 | Planned | — |
| Ubuntu 24.04 AWS | Planned | — |
| Ubuntu 26.04 | Will Not Fix | — |