CVE-2026-74581

Description

In the Linux kernel, the following vulnerability has been resolved: net: ipv6: clear suppressed fib6 rule result fib6_rule_suppress() drops a suppressed route with ip6_rt_put_flags(), but leaves res->rt6 pointing at the released rt6_info. If no later rule supplies a replacement, fib6_rule_lookup() still sees res.rt6 and returns that stale dst to its caller. A suppressing rule can therefore leak a released route back to rt6_lookup(), and the next put hits rcuref_put_slowpath() from dst_release(). Clear res->rt6 when suppressing the route so suppressed lookups fall through to the null dst instead of reusing the released one.

References

• https://git.kernel.org/stable/c/354db6243eca59e9d187ffbf8b7955b044ce84dc
• https://git.kernel.org/stable/c/5d29b286c9de0b309e94b9ed083aa1a2f429434f
• https://git.kernel.org/stable/c/6aea62e433fe1b586202a5fee8b5807ce635e1d7
• https://git.kernel.org/stable/c/6d98c70fe0ba8c7708bfd5b2a5174d2086775daa
• https://git.kernel.org/stable/c/90c57310e266eb94e4a80d6b15a9ca131d2e82cb