CVE-2025-21768

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels<br /> <br /> Some lwtunnels have a dst cache for post-transformation dst.<br /> If the packet destination did not change we may end up recording<br /> a reference to the lwtunnel in its own cache, and the lwtunnel<br /> state will never be freed.<br /> <br /> Discovered by the ioam6.sh test, kmemleak was recently fixed<br /> to catch per-cpu memory leaks. I&amp;#39;m not sure if rpl and seg6<br /> can actually hit this, but in principle I don&amp;#39;t see why not.