In the Linux kernel, the following vulnerability has been resolved: IB/IPoIB: Avoid restoring OPER_UP after multicast flush ipoib_ib_dev_flush_light() temporarily clears IPOIB_FLAG_OPER_UP to prevent multicast joins while ipoib_mcast_dev_flush() is running, and restores the flag afterwards if it was previously set. This restore races with ipoib_ib_dev_down(). If the interface is brought down while the flush is in progress, ipoib_ib_dev_down() clears IPOIB_FLAG_OPER_UP, but the flush path may set it again after the device has already gone down. Since commit 894021a75291 ("IB/ipoib: Make the carrier_on_task race aware"), ipoib_mcast_carrier_on_task() relies on IPOIB_FLAG_OPER_UP being cleared to terminate its rtnl_trylock() retry loop. If the flag is left set after shutdown, the workqueue retries forever, causing teardown to deadlock when ipoib_ndo_uninit() waits in destroy_workqueue() while holding RTNL. Instead of overloading IPOIB_FLAG_OPER_UP to block multicast joins during a light flush, introduce a dedicated IPOIB_FLAG_MCAST_FLUSH flag. Use it together with IPOIB_FLAG_OPER_UP to determine whether multicast joins are allowed, avoiding the race with device shutdown.

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity High

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Key SSVC decision points have not yet been added.

Affected Vendors & Products

Vendors Products
Linux
  • Linux Kernel

No data.

No data.

References
Link Providers
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98347.mbox cve-icon
https://git.kernel.org/stable/c/188b334a6db36a8e0bfaaf59bc4020639a0f3aad cve-icon cve-icon
https://git.kernel.org/stable/c/1b11e4b55b41d9e69a8e8d07622614202e2eaca9 cve-icon cve-icon
https://git.kernel.org/stable/c/1ff3add37c329704ec46181b4ae4f00f9f16ce6f cve-icon cve-icon
https://git.kernel.org/stable/c/326f7d34bd7e64de535566b65c0533b640df5a81 cve-icon cve-icon
https://git.kernel.org/stable/c/5ad925d45f28464a5e043c9620880bb6a030da89 cve-icon cve-icon
https://git.kernel.org/stable/c/9a141d3dc869d18b2eab35e999f4790a9b84e40f cve-icon cve-icon
https://git.kernel.org/stable/c/b72f38929f4b5aa83161fd3b22a7327207e51ec5 cve-icon cve-icon
https://git.kernel.org/stable/c/f973769fb7cb33ba0d4a64b7dcfee0cabaead938 cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2026-98347 cve-icon
https://www.cve.org/CVERecord?id=CVE-2026-98347 cve-icon
History

Sun, 11 Oct 2026 05:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-899

Sun, 11 Oct 2026 03:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-899

Sun, 11 Oct 2026 03:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-899

Sun, 11 Oct 2026 00:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-833
References
Metrics threat_severity

None

 cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate

Wed, 07 Oct 2026 03:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-899

Tue, 06 Oct 2026 19:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-362
CWE-682

Tue, 06 Oct 2026 15:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-362
CWE-682

Tue, 06 Oct 2026 09:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: IB/IPoIB: Avoid restoring OPER_UP after multicast flush ipoib_ib_dev_flush_light() temporarily clears IPOIB_FLAG_OPER_UP to prevent multicast joins while ipoib_mcast_dev_flush() is running, and restores the flag afterwards if it was previously set. This restore races with ipoib_ib_dev_down(). If the interface is brought down while the flush is in progress, ipoib_ib_dev_down() clears IPOIB_FLAG_OPER_UP, but the flush path may set it again after the device has already gone down. Since commit 894021a75291 ("IB/ipoib: Make the carrier_on_task race aware"), ipoib_mcast_carrier_on_task() relies on IPOIB_FLAG_OPER_UP being cleared to terminate its rtnl_trylock() retry loop. If the flag is left set after shutdown, the workqueue retries forever, causing teardown to deadlock when ipoib_ndo_uninit() waits in destroy_workqueue() while holding RTNL. Instead of overloading IPOIB_FLAG_OPER_UP to block multicast joins during a light flush, introduce a dedicated IPOIB_FLAG_MCAST_FLUSH flag. Use it together with IPOIB_FLAG_OPER_UP to determine whether multicast joins are allowed, avoiding the race with device shutdown.
Title IB/IPoIB: Avoid restoring OPER_UP after multicast flush
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2026-10-06T08:46:36.136Z

Updated: 2026-10-19T09:17:58.195Z

Reserved: 2026-09-25T10:25:14.343Z

Link: CVE-2026-98347

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-06T09:18:27.773

Modified: 2026-10-19T10:18:37.207

Link: CVE-2026-98347

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-10-06T00:00:00Z

Links: CVE-2026-98347 - Bugzilla