So you can remotely cause a kernel panic on basically any system with kernel newer than 2.6.28? The doesn't sound great
pending a patch simply disable SACK: ~$ echo 0 > /proc/sys/net/ipv4/tcp_sack
and/or disable segmentation offloading: ~$ ethtool -K eth? tso off
TCP and Checksum offloading still aren't super standard on customer grade NICs or virtual machines. I'd assume less than half of the internet's linux hosts are actually at risk.
Also on the virtualization side, VMWare VMXNet adapters also support offloading for guests.
$ ethtool -k eth0 | grep tcp-seg
tcp-segmentation-offload: on"When Segmentation offload is on and SACK mechanism is also enabled, due to packet loss and selective retransmission of some packets, SKB could end up holding multiple packets, counted by ‘tcp_gso_segs’."
Segmentation offload in linux is dependent on checksum offloads per here:
https://www.kernel.org/doc/Documentation/networking/segmenta...
I thought VMware shipped that at least decade ago — is there some specific sub-feature you had in mind? Similarly, at least Apple's consumer hardware had checksum offloading back in the early 2000s and segmentation support shipped in 10.6 (2009) so it seems like it should be relatively mainstream since they tended to use commodity NIC hardware.
As to the specific subset; TCP Segmentation Offload. As was mentioned in the article.
Yes, I know. I was asking for clarification on the off chance that you were describing something which didn’t ship a decade ago. I first used TSO on servers in the early 2000s and by 2010 even the consumer-grade hardware I was seeing had it.