CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's handling of hardware header lengths in NBMA tunnels using the ip6gre protocol. Incorrect accumulation of the lower device's hardware header length can lead to potential misconfigurations, impacting the integrity of network traffic through these tunnels. Organizations utilizing Linux systems with ip6gre, ip6gretap, or ip6erspan should prioritize addressing this issue to ensure proper network operation and security.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: ip6_gre: fix hardware header length for NBMA tunnels ip6gre_tnl_link_config_route() accumulates the lower device's hardware header length into dev->hard_header_len whenever header_ops is set. This is incorrect for both users of header_ops. ip6gretap and ip6erspan have a fixed Ethernet hardware header length. For an NBMA ip6gre tunnel, ip6gre_header() creates only the GRE header, the optional FOU or GUE header, and the outer IPv6 header. The lower device header is headroom needed later, not part of the tunnel device's hardware header. Keep the lower device header in needed_headroom. Set hard_header_len to the tunnel header length only for ARPHRD_IP6GRE devices with header_ops, and leave the fixed Ethernet header length unchanged for tap and erspan devices.