net: nexthop: Initialize all fields in dumped nexthops

Summary

In the Linux kernel, the following vulnerability has been resolved: net: nexthop: Initialize all fields in dumped nexthops struct nexthop_grp contains two reserved fields that are not initialized by nla_put_nh_group(), and carry garbage. This can be observed e.g. with strace (edited for clarity): ip nexthop add id 1 dev lo ip nexthop add id 101 group 1 strace -e recvmsg ip nexthop get id 101 ... recvmsg(... [{nla_len=12, nla_type=NHA_GROUP}, [{id=1, weight=0, resvd1=0x69, resvd2=0x67}]] ...) = 52 The fields are reserved and therefore not currently used. But as they are, they leak kernel memory, and the fact they are not just zero complicates repurposing of the fields for new ends. Initialize the full structure.

Timeline

1. Aug 17, 2024, 9:08 AM UTCCVE published
2. Sep 10, 2024, 4:11 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Oct 15, 2026, 12:48 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 430a049190de3c9e219f43084de9f1122da04570 · fixed in fd06cb4a5fc7bda3dea31712618a62af72a1c6cb; From 430a049190de3c9e219f43084de9f1122da04570 · fixed in 5cc4d71dda2dd4f1520f40e634a527022e48ccd8; From 430a049190de3c9e219f43084de9f1122da04570 · fixed in 9e8f558a3afe99ce51a642ce0d3637ddc2b5d5d0; From 430a049190de3c9e219f43084de9f1122da04570 · fixed in 1377de719652d868f5317ba8398b7e74c5f0430b; From 430a049190de3c9e219f43084de9f1122da04570 · fixed in 7704460acd7f5d35eb07c52500987dc9b95313fb; From 430a049190de3c9e219f43084de9f1122da04570 · fixed in a13d3864b76ac87085ec530b2ff8e37482a63a96; From 430a049190de3c9e219f43084de9f1122da04570 · fixed in 6d745cd0e9720282cd291d36b9db528aea18add2

• Linux Linux

  5.3

• KernelLinux

  From 5.3.0 · fixed in 5.4.282; From 5.5.0 · fixed in 5.10.224; From 5.11.0 · fixed in 5.15.165; From 5.16.0 · fixed in 6.1.103; From 6.2.0 · fixed in 6.6.44; From 6.7.0 · fixed in 6.10.3

References 7