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.
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
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
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 |
|
|
Projects
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MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-06T08:46:36.136Z
Reserved: 2026-09-25T10:25:14.343Z
Link: CVE-2026-98347
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-10-06T09:18:27.773
Modified: 2026-10-06T09:18:27.773
Link: CVE-2026-98347
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.