kernel/linux.git/include/net/netns, branch v5.18.12

ipv6: make ip6_rt_gc_expire an atomic_t

2022-04-15T21:28:50+00:00

Reads and Writes to ip6_rt_gc_expire always have been racy, as syzbot reported lately [1] There is a possible risk of under-flow, leading to unexpected high value passed to fib6_run_gc(), although I have not observed this in the field. Hosts hitting ip6_dst_gc() very hard are under pretty bad state anyway. [1] BUG: KCSAN: data-race in ip6_dst_gc / ip6_dst_gc read-write to 0xffff888102110744 of 4 bytes by task 13165 on cpu 1: ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311 dst_alloc+0x9b/0x160 net/core/dst.c:86 ip6_dst_alloc net/ipv6/route.c:344 [inline] icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261 mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807 mld_send_cr net/ipv6/mcast.c:2119 [inline] mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289 worker_thread+0x618/0xa70 kernel/workqueue.c:2436 kthread+0x1a9/0x1e0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 read-write to 0xffff888102110744 of 4 bytes by task 11607 on cpu 0: ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311 dst_alloc+0x9b/0x160 net/core/dst.c:86 ip6_dst_alloc net/ipv6/route.c:344 [inline] icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261 mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807 mld_send_cr net/ipv6/mcast.c:2119 [inline] mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289 worker_thread+0x618/0xa70 kernel/workqueue.c:2436 kthread+0x1a9/0x1e0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 value changed: 0x00000bb3 -> 0x00000ba9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 11607 Comm: kworker/0:21 Not tainted 5.18.0-rc1-syzkaller-00037-g42e7a03d3bad-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: mld mld_ifc_work Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: syzbot Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20220413181333.649424-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/

2022-03-19T14:49:08+00:00

ipsec-next Steffen Klassert says: ==================== pull request (net-next): ipsec-next 2022-03-19 1) Delete duplicated functions that calls same xfrm_api_check. From Leon Romanovsky. 2) Align userland API of the default policy structure to the internal structures. From Nicolas Dichtel. ==================== Signed-off-by: David S. Miller

xfrm: rework default policy structure

2022-03-18T06:23:12+00:00

This is a follow up of commit f8d858e607b2 ("xfrm: make user policy API complete"). The goal is to align userland API to the internal structures. Signed-off-by: Nicolas Dichtel Reviewed-by: Antony Antony Signed-off-by: Steffen Klassert

tcp: adjust TSO packet sizes based on min_rtt

2022-03-10T04:05:44+00:00

Back when tcp_tso_autosize() and TCP pacing were introduced, our focus was really to reduce burst sizes for long distance flows. The simple heuristic of using sk_pacing_rate/1024 has worked well, but can lead to too small packets for hosts in the same rack/cluster, when thousands of flows compete for the bottleneck. Neal Cardwell had the idea of making the TSO burst size a function of both sk_pacing_rate and tcp_min_rtt() Indeed, for local flows, sending bigger bursts is better to reduce cpu costs, as occasional losses can be repaired quite fast. This patch is based on Neal Cardwell implementation done more than two years ago. bbr is adjusting max_pacing_rate based on measured bandwidth, while cubic would over estimate max_pacing_rate. /proc/sys/net/ipv4/tcp_tso_rtt_log can be used to tune or disable this new feature, in logarithmic steps. Tested: 100Gbit NIC, two hosts in the same rack, 4K MTU. 600 flows rate-limited to 20000000 bytes per second. Before patch: (TSO sizes would be limited to 20000000/1024/4096 -> 4 segments per TSO) ~# echo 0 >/proc/sys/net/ipv4/tcp_tso_rtt_log ~# nstat -n;perf stat ./super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000;nstat|egrep "TcpInSegs|TcpOutSegs|TcpRetransSegs|Delivered" 96005 Performance counter stats for './super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000': 65,945.29 msec task-clock # 2.845 CPUs utilized 1,314,632 context-switches # 19935.279 M/sec 5,292 cpu-migrations # 80.249 M/sec 940,641 page-faults # 14264.023 M/sec 201,117,030,926 cycles # 3049769.216 GHz (83.45%) 17,699,435,405 stalled-cycles-frontend # 8.80% frontend cycles idle (83.48%) 136,584,015,071 stalled-cycles-backend # 67.91% backend cycles idle (83.44%) 53,809,530,436 instructions # 0.27 insn per cycle # 2.54 stalled cycles per insn (83.36%) 9,062,315,523 branches # 137422329.563 M/sec (83.22%) 153,008,621 branch-misses # 1.69% of all branches (83.32%) 23.182970846 seconds time elapsed TcpInSegs 15648792 0.0 TcpOutSegs 58659110 0.0 # Average of 3.7 4K segments per TSO packet TcpExtTCPDelivered 58654791 0.0 TcpExtTCPDeliveredCE 19 0.0 After patch: ~# echo 9 >/proc/sys/net/ipv4/tcp_tso_rtt_log ~# nstat -n;perf stat ./super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000;nstat|egrep "TcpInSegs|TcpOutSegs|TcpRetransSegs|Delivered" 96046 Performance counter stats for './super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000': 48,982.58 msec task-clock # 2.104 CPUs utilized 186,014 context-switches # 3797.599 M/sec 3,109 cpu-migrations # 63.472 M/sec 941,180 page-faults # 19214.814 M/sec 153,459,763,868 cycles # 3132982.807 GHz (83.56%) 12,069,861,356 stalled-cycles-frontend # 7.87% frontend cycles idle (83.32%) 120,485,917,953 stalled-cycles-backend # 78.51% backend cycles idle (83.24%) 36,803,672,106 instructions # 0.24 insn per cycle # 3.27 stalled cycles per insn (83.18%) 5,947,266,275 branches # 121417383.427 M/sec (83.64%) 87,984,616 branch-misses # 1.48% of all branches (83.43%) 23.281200256 seconds time elapsed TcpInSegs 1434706 0.0 TcpOutSegs 58883378 0.0 # Average of 41 4K segments per TSO packet TcpExtTCPDelivered 58878971 0.0 TcpExtTCPDeliveredCE 9664 0.0 Signed-off-by: Eric Dumazet Reviewed-by: Neal Cardwell Link: https://lore.kernel.org/r/20220309015757.2532973-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski

net/smc: add sysctl for autocorking

2022-03-01T14:25:12+00:00

This add a new sysctl: net.smc.autocorking_size We can dynamically change the behaviour of autocorking by change the value of autocorking_size. Setting to 0 disables autocorking in SMC Signed-off-by: Dust Li Signed-off-by: David S. Miller

net/smc: add sysctl interface for SMC

2022-03-01T14:25:12+00:00

This patch add sysctl interface to support container environment for SMC as we talk in the mail list. Link: https://lore.kernel.org/netdev/20220224020253.GF5443@linux.alibaba.com Co-developed-by: Tony Lu Signed-off-by: Tony Lu Signed-off-by: Dust Li Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2022-02-17T19:44:20+00:00

No conflicts. Signed-off-by: Jakub Kicinski

ipv6: per-netns exclusive flowlabel checks

2022-02-17T04:37:47+00:00

Ipv6 flowlabels historically require a reservation before use. Optionally in exclusive mode (e.g., user-private). Commit 59c820b2317f ("ipv6: elide flowlabel check if no exclusive leases exist") introduced a fastpath that avoids this check when no exclusive leases exist in the system, and thus any flowlabel use will be granted. That allows skipping the control operation to reserve a flowlabel entirely. Though with a warning if the fast path fails: This is an optimization. Robust applications still have to revert to requesting leases if the fast path fails due to an exclusive lease. Still, this is subtle. Better isolate network namespaces from each other. Flowlabels are per-netns. Also record per-netns whether exclusive leases are in use. Then behavior does not change based on activity in other netns. Changes v2 - wrap in IS_ENABLED(CONFIG_IPV6) to avoid breakage if disabled Fixes: 59c820b2317f ("ipv6: elide flowlabel check if no exclusive leases exist") Link: https://lore.kernel.org/netdev/MWHPR2201MB1072BCCCFCE779E4094837ACD0329@MWHPR2201MB1072.namprd22.prod.outlook.com/ Reported-by: Congyu Liu Signed-off-by: Willem de Bruijn Tested-by: Congyu Liu Link: https://lore.kernel.org/r/20220215160037.1976072-1-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski

net/smc: Add global configure for handshake limitation by netlink

2022-02-11T11:14:58+00:00

Although we can control SMC handshake limitation through socket options, which means that applications who need it must modify their code. It's quite troublesome for many existing applications. This patch modifies the global default value of SMC handshake limitation through netlink, providing a way to put constraint on handshake without modifies any code for applications. Suggested-by: Tony Lu Signed-off-by: D. Wythe Reviewed-by: Tony Lu Signed-off-by: David S. Miller

ipv6/addrconf: use one delayed work per netns

2022-02-09T04:41:32+00:00

Next step for using per netns inet6_addr_lst is to have per netns work item to ultimately call addrconf_verify_rtnl() and addrconf_verify() with a new 'struct net*' argument. Everything is still using the global inet6_addr_lst[] table. Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: Jakub Kicinski