Description
In the Linux kernel, the following vulnerability has been resolved:
xfrm6: clear dst.dev on error to avoid double netdev_put in xfrm6_fill_dst()
On the error path where in6_dev_get(dev) returns NULL, xfrm6_fill_dst() releases the device reference with netdev_put() but leaves xdst->u.dst.dev set. dst_destroy() later calls netdev_put(dst->dev) again, so the same net_device reference is released twice, underflowing its refcount (ref_tracker WARNING + "unregister_netdevice: waiting for <dev> to become free").
Clear xdst->u.dst.dev after the netdev_put(), the same way the XFRM device-offload paths xfrm_dev_state_add() and xfrm_dev_policy_add() in net/xfrm/xfrm_device.c NULL ->dev when releasing the reference on error.
ref_tracker: reference already released. ref_tracker: allocated in: xfrm6_fill_dst (net/ipv6/xfrm6_policy.c:86) ... udpv6_sendmsg (net/ipv6/udp.c:1696) ... ref_tracker: freed in: xfrm6_fill_dst (net/ipv6/xfrm6_policy.c:90) ... WARNING: lib/ref_tracker.c:322 at ref_tracker_free+0x58b/0x780 dst_destroy (net/core/dst.c:115) rcu_core handle_softirqs ...
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HWeakness enumeration
Affected software
Source: the vendor's advisory (CNA). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 84c4a9dfbf430861e7588d95ae3ff61535dca351, < 97e032e5733e49471fb73de117ea2ac1ac7c479a; >= 84c4a9dfbf430861e7588d95ae3ff61535dca351, < df6856c2dda9187601d29b5fbd7a81b3b178cedf; >= 84c4a9dfbf430861e7588d95ae3ff61535dca351, < 43de8a49335e611adb271bbd52e84dfbc11fc185; >= 84c4a9dfbf430861e7588d95ae3ff61535dca351, < ff636d7b7cba6dea82ecf580415ea57f2c1a11b6; >= 84c4a9dfbf430861e7588d95ae3ff61535dca351, < e078da1b4e11390cff3201c19a9a1fe70c5b934f; >= 84c4a9dfbf430861e7588d95ae3ff61535dca351, < 136992de9bb91871084ae52d172610541c76e4d2; a7e22d0c0e81dde129a51ee413644124f4b59954; 01b0d887f67a388fb2a658ee2bdd74e5ba146818; a98124aac0b5adc5de8ae54f11322781cb4d85c3; e27b7bee743d921f037b1da6f071237345bef7c1; >= 3.0.79, < 3.1; >= 3.2.46, < 3.3; >= 3.4.46, < 3.5; >= 3.9.3, < 3.10 |
| Linux | Linux | 3.10 |
References
- https://git.kernel.org/stable/c/136992de9bb91871084ae52d172610541c76e4d2
- https://git.kernel.org/stable/c/43de8a49335e611adb271bbd52e84dfbc11fc185
- https://git.kernel.org/stable/c/97e032e5733e49471fb73de117ea2ac1ac7c479a
- https://git.kernel.org/stable/c/df6856c2dda9187601d29b5fbd7a81b3b178cedf
- https://git.kernel.org/stable/c/e078da1b4e11390cff3201c19a9a1fe70c5b934f
- https://git.kernel.org/stable/c/ff636d7b7cba6dea82ecf580415ea57f2c1a11b6
Timeline
- Published
- Aug 5, 2026
- Last modified
- Oct 19, 2026
- NVD status
- Received