CVE-2026-43345

A flaw was found in the Linux kernel's ipa driver. This vulnerability, affecting IPA version 5.0 and later, stems from an incorrect event ring index programming, preventing GSI channels from signaling transfer completions. As a result, the system can experience hangs during operations such as runtime suspend, system suspend, and remoteproc stop. This leads to a Denial of Service (DoS), rendering the IPA data path completely non-functional.

A moderate-severity denial of service flaw was found in the Linux kernel IPA (IP Accelerator) driver, affecting the kernel in Red Hat Enterprise Linux 10 and Red Hat In-Vehicle OS 2. On IPA hardware version 5.0 and later, the event ring index field moved from the CH_C_CNTXT_0 register to CH_C_CNTXT_1, but the v5.0 register definition used the outdated ERINDEX identifier instead of CH_ERINDEX, so the event ring index was never programmed. Without a valid event ring, GSI channels can never signal transfer completions, causing gsi_channel_trans_quiesce() to block forever in wait_for_completion(); runtime suspend, system suspend, and remoteproc stop can hang indefinitely and the IPA data path becomes completely non-functional. The flaw is a local, hardware-specific functional failure on systems with IPA v5.0+ hardware and is not reachable as a remote network attack. Red Hat Enterprise Linux 6, 7, 8, and 9 (kernel and kernel-rt) are not affected because the vulnerable IPA v5.0+ register definitions are not present in those releases. Red Hat rates this flaw Moderate (CVSS 3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H), lower than the Important (7.5) score in the upstream CVE record, because the technical evidence does not support the network attack vector assumed there. Fixes for the affected Red Hat Enterprise Linux 10 and Red Hat In-Vehicle OS 2 kernel streams are currently deferred to a future update; the residual risk is limited to a local denial of service (system hangs and loss of IPA data-path functionality) on systems using affected IPA v5.0+ hardware.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.