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

ipv6/addrconf: fix a potential refcount underflow for idev

Now in addrconf_mod_rs_timer(), reference idev depends on whether
rs_timer is not pending. Then modify rs_timer timeout.

There is a time gap in [1], during which if the pending rs_timer
becomes not pending. It will miss to hold idev, but the rs_timer
is activated. Thus rs_timer callback function addrconf_rs_timer()
will be executed and put idev later without holding idev. A refcount
underflow issue for idev can be caused by this.

if (!timer_pending(&idev->rs_timer))
in6_dev_hold(idev);
<--------------[1]
mod_timer(&idev->rs_timer, jiffies + when);

To fix the issue, hold idev if mod_timer() return 0.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 15 Sep 2025 14:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: ipv6/addrconf: fix a potential refcount underflow for idev Now in addrconf_mod_rs_timer(), reference idev depends on whether rs_timer is not pending. Then modify rs_timer timeout. There is a time gap in [1], during which if the pending rs_timer becomes not pending. It will miss to hold idev, but the rs_timer is activated. Thus rs_timer callback function addrconf_rs_timer() will be executed and put idev later without holding idev. A refcount underflow issue for idev can be caused by this. if (!timer_pending(&idev->rs_timer)) in6_dev_hold(idev); <--------------[1] mod_timer(&idev->rs_timer, jiffies + when); To fix the issue, hold idev if mod_timer() return 0.
Title ipv6/addrconf: fix a potential refcount underflow for idev
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-09-15T14:05:26.685Z

Reserved: 2025-09-15T13:59:19.066Z

Link: CVE-2023-53189

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-09-15T14:15:41.150

Modified: 2025-09-15T15:22:27.090

Link: CVE-2023-53189

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.