In the Linux kernel, the following vulnerability has been resolved:

xfrm: serialize state GC with device state flush

The deferred-device pass in xfrm_dev_state_flush() finds states under
xfrm_state_dev_gc_lock, but drops the lock before calling
xfrm_dev_state_free() because the driver callback may sleep. The device
GC list does not hold an xfrm_state reference, so the state GC worker can
destroy the same state concurrently.

The race can proceed as follows:

CPU 0 CPU 1
find x on the device GC list
drop xfrm_state_dev_gc_lock
read x->xso.dev
xfrm_state_gc_destroy(x)
xfrm_dev_state_free(x)
xfrm_state_free(x)
continue xfrm_dev_state_free(x)

Both paths can invoke the driver callback and drop the device reference.
CPU 0 can also access the xfrm_state after CPU 1 has freed it.

KASAN reported:

BUG: KASAN: slab-use-after-free in xfrm_dev_state_free+0x24c/0x2a0
Read of size 8 at addr ffff88810bbaa960 by task poc/102

Call Trace:
xfrm_dev_state_free+0x24c/0x2a0
xfrm_dev_state_flush+0x353/0x400
xfrm_dev_event+0x26d/0x3a0
notifier_call_chain+0xc0/0x280
__dev_notify_flags+0x169/0x250
netif_change_flags+0xe7/0x160
dev_change_flags+0x96/0x220
devinet_ioctl+0x7f4/0x1880

Allocated by task 87:
xfrm_state_alloc+0x1e/0x5c0
xfrm_add_sa+0xe7f/0x5820
xfrm_user_rcv_msg+0x4f3/0x940

Freed by task 57:
kmem_cache_free+0xcb/0x3d0
xfrm_state_gc_task+0x4a8/0x650
process_one_work+0x63a/0x1070

Serialize xfrm_state destruction against the deferred-device pass with a
mutex. Keep xfrm_state_dev_gc_lock limited to list operations and retain
the existing callback and device-reference release ordering.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 06 Oct 2026 12:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416

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

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: xfrm: serialize state GC with device state flush The deferred-device pass in xfrm_dev_state_flush() finds states under xfrm_state_dev_gc_lock, but drops the lock before calling xfrm_dev_state_free() because the driver callback may sleep. The device GC list does not hold an xfrm_state reference, so the state GC worker can destroy the same state concurrently. The race can proceed as follows: CPU 0 CPU 1 find x on the device GC list drop xfrm_state_dev_gc_lock read x->xso.dev xfrm_state_gc_destroy(x) xfrm_dev_state_free(x) xfrm_state_free(x) continue xfrm_dev_state_free(x) Both paths can invoke the driver callback and drop the device reference. CPU 0 can also access the xfrm_state after CPU 1 has freed it. KASAN reported: BUG: KASAN: slab-use-after-free in xfrm_dev_state_free+0x24c/0x2a0 Read of size 8 at addr ffff88810bbaa960 by task poc/102 Call Trace: xfrm_dev_state_free+0x24c/0x2a0 xfrm_dev_state_flush+0x353/0x400 xfrm_dev_event+0x26d/0x3a0 notifier_call_chain+0xc0/0x280 __dev_notify_flags+0x169/0x250 netif_change_flags+0xe7/0x160 dev_change_flags+0x96/0x220 devinet_ioctl+0x7f4/0x1880 Allocated by task 87: xfrm_state_alloc+0x1e/0x5c0 xfrm_add_sa+0xe7f/0x5820 xfrm_user_rcv_msg+0x4f3/0x940 Freed by task 57: kmem_cache_free+0xcb/0x3d0 xfrm_state_gc_task+0x4a8/0x650 process_one_work+0x63a/0x1070 Serialize xfrm_state destruction against the deferred-device pass with a mutex. Keep xfrm_state_dev_gc_lock limited to list operations and retain the existing callback and device-reference release ordering.
Title xfrm: serialize state GC with device state flush
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-10-06T08:45:05.183Z

Reserved: 2026-09-25T10:25:14.328Z

Link: CVE-2026-98231

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-06T09:18:10.540

Modified: 2026-10-06T09:18:10.540

Link: CVE-2026-98231

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-06T12:15:15Z

Weaknesses