CVE-2026-97477

Received Received - Intake

Memory Leak in Linux Kernel RDMA Counter

Publication date: 2026-09-24

Last updated on: 2026-09-28

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: RDMA/counter: Fix num_counters leak on bind_qp failure in alloc_and_bind() When __rdma_counter_bind_qp() fails in alloc_and_bind(), the error path jumps to err_mode which frees the counter without decrementing port_counter->num_counters. The only place that decrements is rdma_counter_free(), which is unreachable since the counter was never successfully bound. This leak accumulates across repeated failures, permanently preventing the port from switching to AUTO mode (-EBUSY in __counter_set_mode()) and blocking the MANUAL→NONE auto-revert in rdma_counter_free(). When the mode was NONE before the call, the MANUAL mode set by __counter_set_mode() also leaks since the revert logic is never reached. Add an err_bind label between the num_counters increment and the existing err_mode label. It decrements num_counters and mirrors the MANUAL→NONE revert from rdma_counter_free(), ensuring the port state is fully restored on bind failure.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-09-24

Last Modified

2026-09-28

Generated

2026-10-15

AI Q&A

2026-09-25

EPSS Evaluated

2026-10-13

NVD

CVE-2026-97477

EUVD

EUVD-2026-86075

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This is a memory leak vulnerability in the Linux kernel's RDMA (Remote Direct Memory Access) counter subsystem. When binding a queue pair (QP) to a counter fails, the system incorrectly increments a counter tracking the number of bound counters but fails to decrement it during cleanup. This causes the counter to leak, preventing the port from switching to AUTO mode and blocking manual mode cleanup.

Detection Guidance

This vulnerability is specific to the Linux kernel's RDMA counter functionality and may not have direct detection commands. Monitor kernel logs for RDMA-related errors or failures during QP binding attempts. Check for persistent EBUSY errors in rdma_counter-related operations using dmesg or journalctl.

Impact Analysis

The vulnerability can cause resource exhaustion in the RDMA subsystem. Repeated failures may permanently block port mode changes, leading to degraded network performance or complete failure of RDMA operations. Systems relying on RDMA for high-speed data transfer could experience crashes or reduced functionality.

Compliance Impact

This vulnerability does not directly affect compliance with standards like GDPR or HIPAA as it is specific to the Linux kernel's RDMA counter management. Compliance impacts would depend on system configuration and usage rather than this technical flaw.

Mitigation Strategies

Apply the latest Linux kernel patches or updates that include the fix for this vulnerability. Restart affected services or reboot the system to ensure the patched kernel is active. Monitor RDMA operations for errors after applying updates.

Hi! I’m here to help you understand CVE-2026-97477. Ask me anything about the vulnerability, its impact, or mitigation strategies.

0/70