CVE-2026-23386

Updated on 25 Mar 2026

Severity

5.5 Medium severity

Details

CVSS score
5.5

Overview

About vulnerability

In the Linux kernel, the following vulnerability has been resolved: gve: fix incorrect buffer cleanup in gve_tx_clean_pending_packets for QPL In DQ-QPL mode, gve_tx_clean_pending_packets() incorrectly uses the RDA buffer cleanup path. It iterates num_bufs times and attempts to unmap entries in the dma array. This leads to two issues:

  1. The dma array shares storage with tx_qpl_buf_ids (union). Interpreting buffer IDs as DMA addresses results in attempting to unmap incorrect memory locations.
  2. num_bufs in QPL mode (counting 2K chunks) can significantly exceed the size of the dma array, causing out-of-bounds access warnings (trace below is how we noticed this issue). UBSAN: array-index-out-of-bounds in drivers/net/ethernet/drivers/net/ethernet/google/gve/gve_tx_dqo.c:178:5 index 18 is out of range for type ‘dma_addr_t[18]’ (aka ‘unsigned long long[18]’) Workqueue: gve gve_service_task [gve] Call Trace: <TASK> dump_stack_lvl+0x33/0xa0 __ubsan_handle_out_of_bounds+0xdc/0x110 gve_tx_stop_ring_dqo+0x182/0x200 [gve] gve_close+0x1be/0x450 [gve] gve_reset+0x99/0x120 [gve] gve_service_task+0x61/0x100 [gve] process_scheduled_works+0x1e9/0x380 Fix this by properly checking for QPL mode and delegating to gve_free_tx_qpl_bufs() to reclaim the buffers. A flaw was found in the Linux kernel, specifically within the gve network driver. When the driver operates in DQ-QPL (Data Queue - Queue Pair List) mode, the gve_tx_clean_pending_packets() function incorrectly processes buffer cleanup. This error can cause the system to attempt to unmap memory at incorrect locations and access memory outside of allocated bounds, potentially leading to system instability or a denial of service.

Details

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
Debian 13 Planned
Ubuntu 24.04 Planned