CVE-2026-23154

In the Linux kernel, the following vulnerability has been resolved:

net: fix segmentation of forwarding fraglist GRO

This patch enhances GSO segment handling by properly checking

the SKB_GSO_DODGY flag for frag_list GSO packets, addressing

low throughput issues observed when a station accesses IPv4

servers via hotspots with an IPv6-only upstream interface.

Specifically, it fixes a bug in GSO segmentation when forwarding

GRO packets containing a frag_list. The function skb_segment_list

cannot correctly process GRO skbs that have been converted by XLAT,

since XLAT only translates the header of the head skb. Consequently,

skbs in the frag_list may remain untranslated, resulting in protocol

inconsistencies and reduced throughput.

To address this, the patch explicitly sets the SKB_GSO_DODGY flag

for GSO packets in XLAT's IPv4/IPv6 protocol translation helpers

(bpf_skb_proto_4_to_6 and bpf_skb_proto_6_to_4). This marks GSO

packets as potentially modified after protocol translation. As a

result, GSO segmentation will avoid using skb_segment_list and

instead falls back to skb_segment for packets with the SKB_GSO_DODGY

flag. This ensures that only safe and fully translated frag_list

packets are processed by skb_segment_list, resolving protocol

inconsistencies and improving throughput when forwarding GRO packets

converted by XLAT.