There are five patches to fix CVE-2018-5390 in latest mainline branch, but only two patches exist in stable 4.4 and 3.18: dc6ae4d tcp: detect malicious patterns in tcp_collapse_ofo_queue() 5fbec48 tcp: avoid collapses in tcp_prune_queue() if possible but I have tested with these patches, and found the cpu usage was very high. test results: with fix patch： 78.2% ksoftirqd no fix patch： 90% ksoftirqd
After analysing the codes of stable 4.4, and debuging the system, the search of ofo_queue(tcp ofo using a simple queue) cost more cycles. So I think only two patches can't fix the CVE-2018-5390. So I try to backport "tcp: use an RB tree for ooo receive queue" using RB tree instead of simple queue, then backport Eric Dumazet 5 fixed patches in mainline, good news is that ksoftirqd is turn to about 20%, which is the same with mainline now. Eric Dumazet (6): tcp: increment sk_drops for dropped rx packets tcp: free batches of packets in tcp_prune_ofo_queue() tcp: avoid collapses in tcp_prune_queue() if possible tcp: detect malicious patterns in tcp_collapse_ofo_queue() tcp: call tcp_drop() from tcp_data_queue_ofo() tcp: add tcp_ooo_try_coalesce() helper Mao Wenan (2): Revert "tcp: detect malicious patterns in tcp_collapse_ofo_queue()" Revert "tcp: avoid collapses in tcp_prune_queue() if possible" Yaogong Wang (1): tcp: use an RB tree for ooo receive queue include/linux/skbuff.h | 8 + include/linux/tcp.h | 7 +- include/net/sock.h | 7 + include/net/tcp.h | 2 +- net/core/skbuff.c | 19 +++ net/ipv4/tcp.c | 4 +- net/ipv4/tcp_input.c | 412 +++++++++++++++++++++++++++++------------------ net/ipv4/tcp_ipv4.c | 3 +- net/ipv4/tcp_minisocks.c | 1 - net/ipv6/tcp_ipv6.c | 1 + 10 files changed, 294 insertions(+), 170 deletions(-) -- 1.8.3.1
