NetSight
high7.5

CVE-2024-49978

In the Linux kernel, the following vulnerability has been resolved: gso: fix udp gso fraglist segmentation after pull from frag_list Detect gso fraglist skbs w…

Impact

In the Linux kernel, the following vulnerability has been resolved: gso: fix udp gso fraglist segmentation after pull from frag_list Detect gso fraglist skbs with corrupted geometry (see below) and pass these to skb_segment instead of skb_segment_list, as the first can segment them correctly. Valid SKB_GSO_FRAGLIST skbs - consist of two or more segments - the head_skb holds the protocol headers plus first gso_size - one or more frag_list skbs hold exactly one segment - all but the last must be gso_size Optional datapath hooks such as NAT and BPF (bpf_skb_pull_data) can modify these skbs, breaking these invariants. In extreme cases they pull all data into skb linear. For UDP, this causes a NULL ptr deref in __udpv4_gso_segment_list_csum at udp_hdr(seg->next)->dest. Detect invalid geometry due to pull, by checking head_skb size. Don't just drop, as this may blackhole a destination. Convert to be able to pass to regular skb_segment.

Affected products

VendorProductAffected versions
LinuxLinux Kernel
from 5.6 before 6.1.113
from 6.2 before 6.6.55
from 6.7 before 6.10.14
from 6.11 before 6.11.3
Version 6.12

Weakness classification

References