path: root/net/ipv4/tcp_ipv4.c (follow)
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2019-03-11tcp: Don't access TCP_SKB_CB before initializing itChristoph Paasch1-8/+1
Since commit eeea10b83a13 ("tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()"), tcp_vX_fill_cb is only called after tcp_filter(). That means, TCP_SKB_CB(skb)->end_seq still points to the IP-part of the cb. We thus should not mock with it, as this can trigger bugs (thanks syzkaller): [ 12.349396] ================================================================== [ 12.350188] BUG: KASAN: slab-out-of-bounds in ip6_datagram_recv_specific_ctl+0x19b3/0x1a20 [ 12.351035] Read of size 1 at addr ffff88006adbc208 by task test_ip6_datagr/1799 Setting end_seq is actually no more necessary in tcp_filter as it gets initialized later on in tcp_vX_fill_cb. Cc: Eric Dumazet <edumazet@google.com> Fixes: eeea10b83a13 ("tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()") Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-26tcp: convert tcp_md5_needed to static_branch APIEric Dumazet1-1/+1
We prefer static_branch_unlikely() over static_key_false() these days. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+4
Two easily resolvable overlapping change conflicts, one in TCP and one in the eBPF verifier. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-17tcp: tcp_v4_err() should be more carefulEric Dumazet1-1/+4
ICMP handlers are not very often stressed, we should make them more resilient to bugs that might surface in the future. If there is no packet in retransmit queue, we should avoid a NULL deref. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: soukjin bae <soukjin.bae@samsung.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-27tcp: Refactor pingpong codeWei Wang1-1/+1
Instead of using pingpong as a single bit information, we refactor the code to treat it as a counter. When interactive session is detected, we set pingpong count to TCP_PINGPONG_THRESH. And when pingpong count is >= TCP_PINGPONG_THRESH, we consider the session in pingpong mode. This patch is a pure refactor and sets foundation for the next patch. This patch itself does not change any pingpong logic. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-30tcp: md5: add tcp_md5_needed jump labelEric Dumazet1-4/+7
Most linux hosts never setup TCP MD5 keys. We can avoid a cache line miss (accessing tp->md5ig_info) on RX and TX using a jump label. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-30tcp: implement coalescing on backlog queueEric Dumazet1-6/+86
In case GRO is not as efficient as it should be or disabled, we might have a user thread trapped in __release_sock() while softirq handler flood packets up to the point we have to drop. This patch balances work done from user thread and softirq, to give more chances to __release_sock() to complete its work before new packets are added the the backlog. This also helps if we receive many ACK packets, since GRO does not aggregate them. This patch brings ~60% throughput increase on a receiver without GRO, but the spectacular gain is really on 1000x release_sock() latency reduction I have measured. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-20tcp: drop dst in tcp_add_backlog()Eric Dumazet1-0/+2
Under stress, softirq rx handler often hits a socket owned by the user, and has to queue the packet into socket backlog. When this happens, skb dst refcount is taken before we escape rcu protected region. This is done from __sk_add_backlog() calling skb_dst_force(). Consumer will have to perform the opposite costly operation. AFAIK nothing in tcp stack requests the dst after skb was stored in the backlog. If this was the case, we would have had failures already since skb_dst_force() can end up clearing skb dst anyway. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-11tcp: tsq: no longer use limit_output_bytes for paced flowsEric Dumazet1-2/+2
FQ pacing guarantees that paced packets queued by one flow do not add head-of-line blocking for other flows. After TCP GSO conversion, increasing limit_output_bytes to 1 MB is safe, since this maps to 16 skbs at most in qdisc or device queues. (or slightly more if some drivers lower {gso_max_segs|size}) We still can queue at most 1 ms worth of traffic (this can be scaled by wifi drivers if they need to) Tested: # ethtool -c eth0 | egrep "tx-usecs:|tx-frames:" # 40 Gbit mlx4 NIC tx-usecs: 16 tx-frames: 16 # tc qdisc replace dev eth0 root fq # for f in {1..10};do netperf -P0 -H lpaa24,6 -o THROUGHPUT;done Before patch: 27711 26118 27107 27377 27712 27388 27340 27117 27278 27509 After patch: 37434 36949 36658 36998 37711 37291 37605 36659 36544 37349 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-09net: tcp: remove BUG_ON from tcp_v4_errLi RongQing1-1/+0
if skb is NULL pointer, and the following access of skb's skb_mstamp_ns will trigger panic, which is same as BUG_ON Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08net: Convert protocol error handlers from void to intStefano Brivio1-10/+12
We'll need this to handle ICMP errors for tunnels without a sending socket (i.e. FoU and GUE). There, we might have to look up different types of IP tunnels, registered as network protocols, before we get a match, so we want this for the error handlers of IPPROTO_IPIP and IPPROTO_IPV6 in both inet_protos and inet6_protos. These error codes will be used in the next patch. For consistency, return sensible error codes in protocol error handlers whenever handlers can't handle errors because, even if valid, they don't match a protocol or any of its states. This has no effect on existing error handling paths. Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+3
Minor conflict in net/core/rtnetlink.c, David Ahern's bug fix in 'net' overlapped the renaming of a netlink attribute in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02inet: make sure to grab rcu_read_lock before using ireq->ireq_optEric Dumazet1-1/+3
Timer handlers do not imply rcu_read_lock(), so my recent fix triggered a LOCKDEP warning when SYNACK is retransmit. Lets add rcu_read_lock()/rcu_read_unlock() pairs around ireq->ireq_opt usages instead of guessing what is done by callers, since it is not worth the pain. Get rid of ireq_opt_deref() helper since it hides the logic without real benefit, since it is now a standard rcu_dereference(). Fixes: 1ad98e9d1bdf ("tcp/dccp: fix lockdep issue when SYN is backlogged") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-21tcp: introduce tcp_skb_timestamp_us() helperEric Dumazet1-1/+1
There are few places where TCP reads skb->skb_mstamp expecting a value in usec unit. skb->tstamp (aka skb->skb_mstamp) will soon store CLOCK_TAI nsec value. Add tcp_skb_timestamp_us() to provide proper conversion when needed. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-02tcp: remove useless add operation when init sysctl_max_tw_bucketsYafang Shao1-1/+1
cp_hashinfo.ehash_mask is always an odd number, which is set in function alloc_large_system_hash(). See bellow, if (_hash_mask) *_hash_mask = (1 << log2qty) - 1; <<< always odd number Hence the local variable 'cnt' is a even number, as a result of that it is no difference to do the incrementation here. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-22ipv4: tcp: send zero IPID for RST and ACK sent in SYN-RECV and TIME-WAIT stateEric Dumazet1-0/+6
tcp uses per-cpu (and per namespace) sockets (net->ipv4.tcp_sk) internally to send some control packets. 1) RST packets, through tcp_v4_send_reset() 2) ACK packets in SYN-RECV and TIME-WAIT state, through tcp_v4_send_ack() These packets assert IP_DF, and also use the hashed IP ident generator to provide an IPv4 ID number. Geoff Alexander reported this could be used to build off-path attacks. These packets should not be fragmented, since their size is smaller than IPV4_MIN_MTU. Only some tunneled paths could eventually have to fragment, regardless of inner IPID. We really can use zero IPID, to address the flaw, and as a bonus, avoid a couple of atomic operations in ip_idents_reserve() Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Geoff Alexander <alexandg@cs.unm.edu> Tested-by: Geoff Alexander <alexandg@cs.unm.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-20Merge ra.kernel.org:/pub/scm/linux/kernel/git/torvalds/linuxDavid S. Miller1-5/+18
All conflicts were trivial overlapping changes, so reasonably easy to resolve. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12tcp: use monotonic timestamps for PAWSArnd Bergmann1-1/+2
Using get_seconds() for timestamps is deprecated since it can lead to overflows on 32-bit systems. While the interface generally doesn't overflow until year 2106, the specific implementation of the TCP PAWS algorithm breaks in 2038 when the intermediate signed 32-bit timestamps overflow. A related problem is that the local timestamps in CLOCK_REALTIME form lead to unexpected behavior when settimeofday is called to set the system clock backwards or forwards by more than 24 days. While the first problem could be solved by using an overflow-safe method of comparing the timestamps, a nicer solution is to use a monotonic clocksource with ktime_get_seconds() that simply doesn't overflow (at least not until 136 years after boot) and that doesn't change during settimeofday(). To make 32-bit and 64-bit architectures behave the same way here, and also save a few bytes in the tcp_options_received structure, I'm changing the type to a 32-bit integer, which is now safe on all architectures. Finally, the ts_recent_stamp field also (confusingly) gets used to store a jiffies value in tcp_synq_overflow()/tcp_synq_no_recent_overflow(). This is currently safe, but changing the type to 32-bit requires some small changes there to keep it working. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12tcp: fix sequence numbers for repaired sockets re-using TIME-WAIT socketsStefan Baranoff1-5/+18
This patch fixes a bug where the sequence numbers of a socket created using TCP repair functionality are lower than set after connect is called. This occurs when the repair socket overlaps with a TIME-WAIT socket and triggers the re-use code. The amount lower is equal to the number of times that a particular IP/port set is re-used and then put back into TIME-WAIT. Re-using the first time the sequence number is 1 lower, closing that socket and then re-opening (with repair) a new socket with the same addresses/ports puts the sequence number 2 lower than set via setsockopt. The third time is 3 lower, etc. I have not tested what the limit of this acrewal is, if any. The fix is, if a socket is in repair mode, to respect the already set sequence number and timestamp when it would have already re-used the TIME-WAIT socket. Signed-off-by: Stefan Baranoff <sbaranoff@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-14tcp: verify the checksum of the first data segment in a new connectionFrank van der Linden1-0/+4
commit 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") introduced an optimization for the handling of child sockets created for a new TCP connection. But this optimization passes any data associated with the last ACK of the connection handshake up the stack without verifying its checksum, because it calls tcp_child_process(), which in turn calls tcp_rcv_state_process() directly. These lower-level processing functions do not do any checksum verification. Insert a tcp_checksum_complete call in the TCP_NEW_SYN_RECEIVE path to fix this. Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") Signed-off-by: Frank van der Linden <fllinden@amazon.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-6/+49
Pull networking updates from David Miller: 1) Add Maglev hashing scheduler to IPVS, from Inju Song. 2) Lots of new TC subsystem tests from Roman Mashak. 3) Add TCP zero copy receive and fix delayed acks and autotuning with SO_RCVLOWAT, from Eric Dumazet. 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard Brouer. 5) Add ttl inherit support to vxlan, from Hangbin Liu. 6) Properly separate ipv6 routes into their logically independant components. fib6_info for the routing table, and fib6_nh for sets of nexthops, which thus can be shared. From David Ahern. 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP messages from XDP programs. From Nikita V. Shirokov. 8) Lots of long overdue cleanups to the r8169 driver, from Heiner Kallweit. 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau. 10) Add traffic condition monitoring to iwlwifi, from Luca Coelho. 11) Plumb extack down into fib_rules, from Roopa Prabhu. 12) Add Flower classifier offload support to igb, from Vinicius Costa Gomes. 13) Add UDP GSO support, from Willem de Bruijn. 14) Add documentation for eBPF helpers, from Quentin Monnet. 15) Add TLS tx offload to mlx5, from Ilya Lesokhin. 16) Allow applications to be given the number of bytes available to read on a socket via a control message returned from recvmsg(), from Soheil Hassas Yeganeh. 17) Add x86_32 eBPF JIT compiler, from Wang YanQing. 18) Add AF_XDP sockets, with zerocopy support infrastructure as well. From Björn Töpel. 19) Remove indirect load support from all of the BPF JITs and handle these operations in the verifier by translating them into native BPF instead. From Daniel Borkmann. 20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha. 21) Allow XDP programs to do lookups in the main kernel routing tables for forwarding. From David Ahern. 22) Allow drivers to store hardware state into an ELF section of kernel dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy. 23) Various RACK and loss detection improvements in TCP, from Yuchung Cheng. 24) Add TCP SACK compression, from Eric Dumazet. 25) Add User Mode Helper support and basic bpfilter infrastructure, from Alexei Starovoitov. 26) Support ports and protocol values in RTM_GETROUTE, from Roopa Prabhu. 27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard Brouer. 28) Add lots of forwarding selftests, from Petr Machata. 29) Add generic network device failover driver, from Sridhar Samudrala. * ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits) strparser: Add __strp_unpause and use it in ktls. rxrpc: Fix terminal retransmission connection ID to include the channel net: hns3: Optimize PF CMDQ interrupt switching process net: hns3: Fix for VF mailbox receiving unknown message net: hns3: Fix for VF mailbox cannot receiving PF response bnx2x: use the right constant Revert "net: sched: cls: Fix offloading when ingress dev is vxlan" net: dsa: b53: Fix for brcm tag issue in Cygnus SoC enic: fix UDP rss bits netdev-FAQ: clarify DaveM's position for stable backports rtnetlink: validate attributes in do_setlink() mlxsw: Add extack messages for port_{un, }split failures netdevsim: Add extack error message for devlink reload devlink: Add extack to reload and port_{un, }split operations net: metrics: add proper netlink validation ipmr: fix error path when ipmr_new_table fails ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds net: hns3: remove unused hclgevf_cfg_func_mta_filter netfilter: provide udp*_lib_lookup for nf_tproxy qed*: Utilize FW ...
2018-06-04net-tcp: extend tcp_tw_reuse sysctl to enable loopback only optimizationMaciej Żenczykowski1-3/+32
This changes the /proc/sys/net/ipv4/tcp_tw_reuse from a boolean to an integer. It now takes the values 0, 1 and 2, where 0 and 1 behave as before, while 2 enables timewait socket reuse only for sockets that we can prove are loopback connections: ie. bound to 'lo' interface or where one of source or destination IPs is, ::ffff: or ::1. This enables quicker reuse of ephemeral ports for loopback connections - where tcp_tw_reuse is 100% safe from a protocol perspective (this assumes no artificially induced packet loss on 'lo'). This also makes estblishing many loopback connections *much* faster (allocating ports out of the first half of the ephemeral port range is significantly faster, then allocating from the second half) Without this change in a 32K ephemeral port space my sample program (it just establishes and closes [::1]:ephemeral -> [::1]:server_port connections in a tight loop) fails after 32765 connections in 24 seconds. With it enabled 50000 connections only take 4.7 seconds. This is particularly problematic for IPv6 where we only have one local address and cannot play tricks with varying source IP from pool. Signed-off-by: Maciej Żenczykowski <maze@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Wei Wang <weiwan@google.com> Change-Id: I0377961749979d0301b7b62871a32a4b34b654e1 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-31tcp: minor optimization around tcp_hdr() usage in receive pathYafang Shao1-1/+1
This is additional to the commit ea1627c20c34 ("tcp: minor optimizations around tcp_hdr() usage"). At this point, skb->data is same with tcp_hdr() as tcp header has not been pulled yet. So use the less expensive one to get the tcp header. Remove the third parameter of tcp_rcv_established() and put it into the function body. Furthermore, the local variables are listed as a reverse christmas tree :) Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-18tcp: add tcp_comp_sack_nr sysctlEric Dumazet1-0/+1
This per netns sysctl allows for TCP SACK compression fine-tuning. This limits number of SACK that can be compressed. Using 0 disables SACK compression. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-18tcp: add tcp_comp_sack_delay_ns sysctlEric Dumazet1-0/+1
This per netns sysctl allows for TCP SACK compression fine-tuning. Its default value is 1,000,000, or 1 ms to meet TSO autosizing period. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-16proc: introduce proc_create_net{,_data}Christoph Hellwig1-15/+2
Variants of proc_create{,_data} that directly take a struct seq_operations and deal with network namespaces in ->open and ->release. All callers of proc_create + seq_open_net converted over, and seq_{open,release}_net are removed entirely. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16ipv{4,6}/tcp: simplify procfs registrationChristoph Hellwig1-54/+31
Avoid most of the afinfo indirections and just call the proc helpers directly. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-10tcp: Add mark for TIMEWAIT socketsJon Maxwell1-2/+14
This version has some suggestions by Eric Dumazet: - Use a local variable for the mark in IPv6 instead of ctl_sk to avoid SMP races. - Use the more elegant "IP4_REPLY_MARK(net, skb->mark) ?: sk->sk_mark" statement. - Factorize code as sk_fullsock() check is not necessary. Aidan McGurn from Openwave Mobility systems reported the following bug: "Marked routing is broken on customer deployment. Its effects are large increase in Uplink retransmissions caused by the client never receiving the final ACK to their FINACK - this ACK misses the mark and routes out of the incorrect route." Currently marks are added to sk_buffs for replies when the "fwmark_reflect" sysctl is enabled. But not for TW sockets that had sk->sk_mark set via setsockopt(SO_MARK..). Fix this in IPv4/v6 by adding tw->tw_mark for TIME_WAIT sockets. Copy the the original sk->sk_mark in __inet_twsk_hashdance() to the new tw->tw_mark location. Then progate this so that the skb gets sent with the correct mark. Do the same for resets. Give the "fwmark_reflect" sysctl precedence over sk->sk_mark so that netfilter rules are still honored. Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller1-0/+16
Daniel Borkmann says: ==================== pull-request: bpf-next 2018-03-31 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Add raw BPF tracepoint API in order to have a BPF program type that can access kernel internal arguments of the tracepoints in their raw form similar to kprobes based BPF programs. This infrastructure also adds a new BPF_RAW_TRACEPOINT_OPEN command to BPF syscall which returns an anon-inode backed fd for the tracepoint object that allows for automatic detach of the BPF program resp. unregistering of the tracepoint probe on fd release, from Alexei. 2) Add new BPF cgroup hooks at bind() and connect() entry in order to allow BPF programs to reject, inspect or modify user space passed struct sockaddr, and as well a hook at post bind time once the port has been allocated. They are used in FB's container management engine for implementing policy, replacing fragile LD_PRELOAD wrapper intercepting bind() and connect() calls that only works in limited scenarios like glibc based apps but not for other runtimes in containerized applications, from Andrey. 3) BPF_F_INGRESS flag support has been added to sockmap programs for their redirect helper call bringing it in line with cls_bpf based programs. Support is added for both variants of sockmap programs, meaning for tx ULP hooks as well as recv skb hooks, from John. 4) Various improvements on BPF side for the nfp driver, besides others this work adds BPF map update and delete helper call support from the datapath, JITing of 32 and 64 bit XADD instructions as well as offload support of bpf_get_prandom_u32() call. Initial implementation of nfp packet cache has been tackled that optimizes memory access (see merge commit for further details), from Jakub and Jiong. 5) Removal of struct bpf_verifier_env argument from the print_bpf_insn() API has been done in order to prepare to use print_bpf_insn() soon out of perf tool directly. This makes the print_bpf_insn() API more generic and pushes the env into private data. bpftool is adjusted as well with the print_bpf_insn() argument removal, from Jiri. 6) Couple of cleanups and prep work for the upcoming BTF (BPF Type Format). The latter will reuse the current BPF verifier log as well, thus bpf_verifier_log() is further generalized, from Martin. 7) For bpf_getsockopt() and bpf_setsockopt() helpers, IPv4 IP_TOS read and write support has been added in similar fashion to existing IPv6 IPV6_TCLASS socket option we already have, from Nikita. 8) Fixes in recent sockmap scatterlist API usage, which did not use sg_init_table() for initialization thus triggering a BUG_ON() in scatterlist API when CONFIG_DEBUG_SG was enabled. This adds and uses a small helper sg_init_marker() to properly handle the affected cases, from Prashant. 9) Let the BPF core follow IDR code convention and therefore use the idr_preload() and idr_preload_end() helpers, which would also help idr_alloc_cyclic() under GFP_ATOMIC to better succeed under memory pressure, from Shaohua. 10) Last but not least, a spelling fix in an error message for the BPF cookie UID helper under BPF sample code, from Colin. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-31bpf: Hooks for sys_connectAndrey Ignatov1-0/+16
== The problem == See description of the problem in the initial patch of this patch set. == The solution == The patch provides much more reliable in-kernel solution for the 2nd part of the problem: making outgoing connecttion from desired IP. It adds new attach types `BPF_CGROUP_INET4_CONNECT` and `BPF_CGROUP_INET6_CONNECT` for program type `BPF_PROG_TYPE_CGROUP_SOCK_ADDR` that can be used to override both source and destination of a connection at connect(2) time. Local end of connection can be bound to desired IP using newly introduced BPF-helper `bpf_bind()`. It allows to bind to only IP though, and doesn't support binding to port, i.e. leverages `IP_BIND_ADDRESS_NO_PORT` socket option. There are two reasons for this: * looking for a free port is expensive and can affect performance significantly; * there is no use-case for port. As for remote end (`struct sockaddr *` passed by user), both parts of it can be overridden, remote IP and remote port. It's useful if an application inside cgroup wants to connect to another application inside same cgroup or to itself, but knows nothing about IP assigned to the cgroup. Support is added for IPv4 and IPv6, for TCP and UDP. IPv4 and IPv6 have separate attach types for same reason as sys_bind hooks, i.e. to prevent reading from / writing to e.g. user_ip6 fields when user passes sockaddr_in since it'd be out-of-bound. == Implementation notes == The patch introduces new field in `struct proto`: `pre_connect` that is a pointer to a function with same signature as `connect` but is called before it. The reason is in some cases BPF hooks should be called way before control is passed to `sk->sk_prot->connect`. Specifically `inet_dgram_connect` autobinds socket before calling `sk->sk_prot->connect` and there is no way to call `bpf_bind()` from hooks from e.g. `ip4_datagram_connect` or `ip6_datagram_connect` since it'd cause double-bind. On the other hand `proto.pre_connect` provides a flexible way to add BPF hooks for connect only for necessary `proto` and call them at desired time before `connect`. Since `bpf_bind()` is allowed to bind only to IP and autobind in `inet_dgram_connect` binds only port there is no chance of double-bind. bpf_bind() sets `force_bind_address_no_port` to bind to only IP despite of value of `bind_address_no_port` socket field. bpf_bind() sets `with_lock` to `false` when calling to __inet_bind() and __inet6_bind() since all call-sites, where bpf_bind() is called, already hold socket lock. Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-27net: Drop pernet_operations::asyncKirill Tkhai1-2/+0
Synchronous pernet_operations are not allowed anymore. All are asynchronous. So, drop the structure member. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-26net: Use octal not symbolic permissionsJoe Perches1-1/+1
Prefer the direct use of octal for permissions. Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace and some typing. Miscellanea: o Whitespace neatening around these conversions. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-21tcp: remove dead code after CHECKSUM_PARTIAL adoptionEric Dumazet1-10/+3
Since all skbs in write/rtx queues have CHECKSUM_PARTIAL, we can remove dead code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-14tcp: try to keep packet if SYN_RCV race is lostEric Dumazet1-1/+12
배석진 reported that in some situations, packets for a given 5-tuple end up being processed by different CPUS. This involves RPS, and fragmentation. 배석진 is seeing packet drops when a SYN_RECV request socket is moved into ESTABLISH state. Other states are protected by socket lock. This is caused by a CPU losing the race, and simply not caring enough. Since this seems to occur frequently, we can do better and perform a second lookup. Note that all needed memory barriers are already in the existing code, thanks to the spin_lock()/spin_unlock() pair in inet_ehash_insert() and reqsk_put(). The second lookup must find the new socket, unless it has already been accepted and closed by another cpu. Note that the fragmentation could be avoided in the first place by use of a correct TCP MSS option in the SYN{ACK} packet, but this does not mean we can not be more robust. Many thanks to 배석진 for a very detailed analysis. Reported-by: 배석진 <soukjin.bae@samsung.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-13net: Convert pernet_subsys, registered from inet_init()Kirill Tkhai1-0/+2
arp_net_ops just addr/removes /proc entry. devinet_ops allocates and frees duplicate of init_net tables and (un)registers sysctl entries. fib_net_ops allocates and frees pernet tables, creates/destroys netlink socket and (un)initializes /proc entries. Foreign pernet_operations do not touch them. ip_rt_proc_ops only modifies pernet /proc entries. xfrm_net_ops creates/destroys /proc entries, allocates/frees pernet statistics, hashes and tables, and (un)initializes sysctl files. These are not touched by foreigh pernet_operations xfrm4_net_ops allocates/frees private pernet memory, and configures sysctls. sysctl_route_ops creates/destroys sysctls. rt_genid_ops only initializes fields of just allocated net. ipv4_inetpeer_ops allocated/frees net private memory. igmp_net_ops just creates/destroys /proc files and socket, noone else interested in. tcp_sk_ops seems to be safe, because tcp_sk_init() does not depend on any other pernet_operations modifications. Iteration over hash table in inet_twsk_purge() is made under RCU lock, and it's safe to iterate the table this way. Removing from the table happen from inet_twsk_deschedule_put(), but this function is safe without any extern locks, as it's synchronized inside itself. There are many examples, it's used in different context. So, it's safe to leave tcp_sk_exit_batch() unlocked. tcp_net_metrics_ops is synchronized on tcp_metrics_lock and safe. udplite4_net_ops only creates/destroys pernet /proc file. icmp_sk_ops creates percpu sockets, not touched by foreign pernet_operations. ipmr_net_ops creates/destroys pernet fib tables, (un)registers fib rules and /proc files. This seem to be safe to execute in parallel with foreign pernet_operations. af_inet_ops just sets up default parameters of newly created net. ipv4_mib_ops creates and destroys pernet percpu statistics. raw_net_ops, tcp4_net_ops, udp4_net_ops, ping_v4_net_ops and ip_proc_ops only create/destroy pernet /proc files. ip4_frags_ops creates and destroys sysctl file. So, it's safe to make the pernet_operations async. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Acked-by: Andrei Vagin <avagin@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-07tcp: tracepoint: only call trace_tcp_send_reset with full socketSong Liu1-1/+2
tracepoint tcp_send_reset requires a full socket to work. However, it may be called when in TCP_TIME_WAIT: case TCP_TW_RST: tcp_v6_send_reset(sk, skb); inet_twsk_deschedule_put(inet_twsk(sk)); goto discard_it; To avoid this problem, this patch checks the socket with sk_fullsock() before calling trace_tcp_send_reset(). Fixes: c24b14c46bb8 ("tcp: add tracepoint trace_tcp_send_reset") Signed-off-by: Song Liu <songliubraving@fb.com> Reviewed-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-16net: delete /proc THIS_MODULE referencesAlexey Dobriyan1-1/+0
/proc has been ignoring struct file_operations::owner field for 10 years. Specifically, it started with commit 786d7e1612f0b0adb6046f19b906609e4fe8b1ba ("Fix rmmod/read/write races in /proc entries"). Notice the chunk where inode->i_fop is initialized with proxy struct file_operations for regular files: - if (de->proc_fops) - inode->i_fop = de->proc_fops; + if (de->proc_fops) { + if (S_ISREG(inode->i_mode)) + inode->i_fop = &proc_reg_file_ops; + else + inode->i_fop = de->proc_fops; + } VFS stopped pinning module at this point. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-26tcp: md5: Handle RCU dereference of md5sig_infoMat Martineau1-1/+1
Dereference tp->md5sig_info in tcp_v4_destroy_sock() the same way it is done in the adjacent call to tcp_clear_md5_list(). Resolves this sparse warning: net/ipv4/tcp_ipv4.c:1914:17: warning: incorrect type in argument 1 (different address spaces) net/ipv4/tcp_ipv4.c:1914:17: expected struct callback_head *head net/ipv4/tcp_ipv4.c:1914:17: got struct callback_head [noderef] <asn:4>*<noident> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Acked-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-20net: sock: replace sk_state_load with inet_sk_state_load and remove sk_state_storeYafang Shao1-1/+1
sk_state_load is only used by AF_INET/AF_INET6, so rename it to inet_sk_state_load and move it into inet_sock.h. sk_state_store is removed as it is not used any more. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-12tcp md5sig: Use skb's saddr when replying to an incoming segmentChristoph Paasch1-1/+1
The MD5-key that belongs to a connection is identified by the peer's IP-address. When we are in tcp_v4(6)_reqsk_send_ack(), we are replying to an incoming segment from tcp_check_req() that failed the seq-number checks. Thus, to find the correct key, we need to use the skb's saddr and not the daddr. This bug seems to have been there since quite a while, but probably got unnoticed because the consequences are not catastrophic. We will call tcp_v4_reqsk_send_ack only to send a challenge-ACK back to the peer, thus the connection doesn't really fail. Fixes: 9501f9722922 ("tcp md5sig: Let the caller pass appropriate key for tcp_v{4,6}_do_calc_md5_hash().") Signed-off-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-03tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()Eric Dumazet1-19/+40
James Morris reported kernel stack corruption bug [1] while running the SELinux testsuite, and bisected to a recent commit bffa72cf7f9d ("net: sk_buff rbnode reorg") We believe this commit is fine, but exposes an older bug. SELinux code runs from tcp_filter() and might send an ICMP, expecting IP options to be found in skb->cb[] using regular IPCB placement. We need to defer TCP mangling of skb->cb[] after tcp_filter() calls. This patch adds tcp_v4_fill_cb()/tcp_v4_restore_cb() in a very similar way we added them for IPv6. [1] [ 339.806024] SELinux: failure in selinux_parse_skb(), unable to parse packet [ 339.822505] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff81745af5 [ 339.822505] [ 339.852250] CPU: 4 PID: 3642 Comm: client Not tainted 4.15.0-rc1-test #15 [ 339.868498] Hardware name: LENOVO 10FGS0VA1L/30BC, BIOS FWKT68A 01/19/2017 [ 339.885060] Call Trace: [ 339.896875] <IRQ> [ 339.908103] dump_stack+0x63/0x87 [ 339.920645] panic+0xe8/0x248 [ 339.932668] ? ip_push_pending_frames+0x33/0x40 [ 339.946328] ? icmp_send+0x525/0x530 [ 339.958861] ? kfree_skbmem+0x60/0x70 [ 339.971431] __stack_chk_fail+0x1b/0x20 [ 339.984049] icmp_send+0x525/0x530 [ 339.996205] ? netlbl_skbuff_err+0x36/0x40 [ 340.008997] ? selinux_netlbl_err+0x11/0x20 [ 340.021816] ? selinux_socket_sock_rcv_skb+0x211/0x230 [ 340.035529] ? security_sock_rcv_skb+0x3b/0x50 [ 340.048471] ? sk_filter_trim_cap+0x44/0x1c0 [ 340.061246] ? tcp_v4_inbound_md5_hash+0x69/0x1b0 [ 340.074562] ? tcp_filter+0x2c/0x40 [ 340.086400] ? tcp_v4_rcv+0x820/0xa20 [ 340.098329] ? ip_local_deliver_finish+0x71/0x1a0 [ 340.111279] ? ip_local_deliver+0x6f/0xe0 [ 340.123535] ? ip_rcv_finish+0x3a0/0x3a0 [ 340.135523] ? ip_rcv_finish+0xdb/0x3a0 [ 340.147442] ? ip_rcv+0x27c/0x3c0 [ 340.158668] ? inet_del_offload+0x40/0x40 [ 340.170580] ? __netif_receive_skb_core+0x4ac/0x900 [ 340.183285] ? rcu_accelerate_cbs+0x5b/0x80 [ 340.195282] ? __netif_receive_skb+0x18/0x60 [ 340.207288] ? process_backlog+0x95/0x140 [ 340.218948] ? net_rx_action+0x26c/0x3b0 [ 340.230416] ? __do_softirq+0xc9/0x26a [ 340.241625] ? do_softirq_own_stack+0x2a/0x40 [ 340.253368] </IRQ> [ 340.262673] ? do_softirq+0x50/0x60 [ 340.273450] ? __local_bh_enable_ip+0x57/0x60 [ 340.285045] ? ip_finish_output2+0x175/0x350 [ 340.296403] ? ip_finish_output+0x127/0x1d0 [ 340.307665] ? nf_hook_slow+0x3c/0xb0 [ 340.318230] ? ip_output+0x72/0xe0 [ 340.328524] ? ip_fragment.constprop.54+0x80/0x80 [ 340.340070] ? ip_local_out+0x35/0x40 [ 340.350497] ? ip_queue_xmit+0x15c/0x3f0 [ 340.361060] ? __kmalloc_reserve.isra.40+0x31/0x90 [ 340.372484] ? __skb_clone+0x2e/0x130 [ 340.382633] ? tcp_transmit_skb+0x558/0xa10 [ 340.393262] ? tcp_connect+0x938/0xad0 [ 340.403370] ? ktime_get_with_offset+0x4c/0xb0 [ 340.414206] ? tcp_v4_connect+0x457/0x4e0 [ 340.424471] ? __inet_stream_connect+0xb3/0x300 [ 340.435195] ? inet_stream_connect+0x3b/0x60 [ 340.445607] ? SYSC_connect+0xd9/0x110 [ 340.455455] ? __audit_syscall_entry+0xaf/0x100 [ 340.466112] ? syscall_trace_enter+0x1d0/0x2b0 [ 340.476636] ? __audit_syscall_exit+0x209/0x290 [ 340.487151] ? SyS_connect+0xe/0x10 [ 340.496453] ? do_syscall_64+0x67/0x1b0 [ 340.506078] ? entry_SYSCALL64_slow_path+0x25/0x25 Fixes: 971f10eca186 ("tcp: better TCP_SKB_CB layout to reduce cache line misses") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: James Morris <james.l.morris@oracle.com> Tested-by: James Morris <james.l.morris@oracle.com> Tested-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-15tcp: Namespace-ify sysctl_tcp_default_congestion_controlStephen Hemminger1-0/+9
Make default TCP default congestion control to a per namespace value. This changes default congestion control to a pointer to congestion ops (rather than implicit as first element of available lsit). The congestion control setting of new namespaces is inherited from the current setting of the root namespace. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-10tcp: Namespace-ify sysctl_tcp_rmem and sysctl_tcp_wmemEric Dumazet1-3/+10
Note that when a new netns is created, it inherits its sysctl_tcp_rmem and sysctl_tcp_wmem from initial netns. This change is needed so that we can refine TCP rcvbuf autotuning, to take RTT into consideration. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
Several conflicts here. NFP driver bug fix adding nfp_netdev_is_nfp_repr() check to nfp_fl_output() needed some adjustments because the code block is in an else block now. Parallel additions to net/pkt_cls.h and net/sch_generic.h A bug fix in __tcp_retransmit_skb() conflicted with some of the rbtree changes in net-next. The tc action RCU callback fixes in 'net' had some overlap with some of the recent tcf_block reworking. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-28tcp: Namespace-ify sysctl_tcp_pacing_ca_ratioEric Dumazet1-0/+1
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-28tcp: Namespace-ify sysctl_tcp_pacing_ss_ratioEric Dumazet1-0/+1
Also remove an obsolete comment about TCP pacing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-28tcp: Namespace-ify sysctl_tcp_invalid_ratelimitEric Dumazet1-0/+1
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-28tcp: Namespace-ify sysctl_tcp_autocorkingEric Dumazet1-0/+1
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-28tcp: Namespace-ify sysctl_tcp_min_rtt_wlenEric Dumazet1-0/+1
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-28tcp: Namespace-ify sysctl_tcp_min_tso_segsEric Dumazet1-0/+1
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>