Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
netfilter: reject zero shift in nft_bitwise
Reject zero shift operands for nft_bitwise left and right shift expressions during initialization.
The carry propagation logic computes the carry from the adjacent 32-bit word using BITS_PER_TYPE(u32) - shift. A zero shift operand turns this into a 32-bit shift, which is undefined behaviour.
Reject zero shift operands in the control plane, alongside the existing check for values greater than or equal to 32, so malformed rules never reach the packet path.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , TuxCare 9.6 ESU , Ubuntu 20.04 ELS
- Affected packages:
- linux-meta @ 5.4.0 (+3 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Amazon Linux 2023 | Planned | — |
| Debian 11 | Planned | — |
| Debian 11 cloud | Planned | — |
| Debian 12 | Planned | — |
| Debian 13 | Released |
6 kernels
|
| Ubuntu 22.04 | Planned | — |
| Ubuntu 24.04 | Planned | — |