CVE-2026-68129

Status: UPDATED  |  Advisory ID: CVE-2026-68129

Key Details

Affected Products, Subsystems & Sectors

What to Know

In the Linux kernel, the following vulnerability has been resolved:

gve: fix Rx queue stall on alloc failure

When the system is under extreme memory pressure, page allocations can

fail during the Rx buffer refill loop. If the number of buffers posted

to hardware falls below a critical low threshold and the refill loop

exits due to allocation failures, the queue can stall:

1. The device drops incoming packets because there are no descriptors.

2. Since no packets are processed, no Rx completions are generated.

3. Because no completions occur, NAPI is never scheduled, preventing

the refill loop from running again even after memory is freed.

This results in a permanent queue stall.

Resolve this by introducing a starvation recovery timer for each Rx queue.

If the number of buffers posted to hardware falls below a critical low

threshold, start a timer to periodically reschedule NAPI. Once NAPI runs

and successfully refills the queue above the threshold, the timer is

not rescheduled.

The threshold is set to 32 because a single maximum-sized Receive Segment

Coalescing (RSC) packet can consume up to 19 descriptors in the Rx path.

Lower thresholds (such as 8 or 16) would be insufficient to process a

complete maximum-sized RSC packet, risking packet drops or unexpected

hardware behavior under memory pressure. Setting the threshold to 32

guarantees a safe margin to handle at least one full RSC packet. (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References