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2018-12-01tcp: do not release socket ownership in tcp_close()Eric Dumazet
commit 8873c064d1de579ea23412a6d3eee972593f142b upstream. syzkaller was able to hit the WARN_ON(sock_owned_by_user(sk)); in tcp_close() While a socket is being closed, it is very possible other threads find it in rtnetlink dump. tcp_get_info() will acquire the socket lock for a short amount of time (slow = lock_sock_fast(sk)/unlock_sock_fast(sk, slow);), enough to trigger the warning. Fixes: 67db3e4bfbc9 ("tcp: no longer hold ehash lock while calling tcp_get_info()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-23inet: frags: better deal with smp racesEric Dumazet
[ Upstream commit 0d5b9311baf27bb545f187f12ecfd558220c607d ] Multiple cpus might attempt to insert a new fragment in rhashtable, if for example RPS is buggy, as reported by 배석진 in https://patchwork.ozlabs.org/patch/994601/ We use rhashtable_lookup_get_insert_key() instead of rhashtable_insert_fast() to let cpus losing the race free their own inet_frag_queue and use the one that was inserted by another cpu. Fixes: 648700f76b03 ("inet: frags: use rhashtables for reassembly units") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: 배석진 <soukjin.bae@samsung.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-23tcp: Fix SOF_TIMESTAMPING_RX_HARDWARE to use the latest timestamp during TCP ↵Stephen Mallon
coalescing [ Upstream commit cadf9df27e7cf40e390e060a1c71bb86ecde798b ] During tcp coalescing ensure that the skb hardware timestamp refers to the highest sequence number data. Previously only the software timestamp was updated during coalescing. Signed-off-by: Stephen Mallon <stephen.mallon@sydney.edu.au> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-23ip_tunnel: don't force DF when MTU is lockedSabrina Dubroca
[ Upstream commit 16f7eb2b77b55da816c4e207f3f9440a8cafc00a ] The various types of tunnels running over IPv4 can ask to set the DF bit to do PMTU discovery. However, PMTU discovery is subject to the threshold set by the net.ipv4.route.min_pmtu sysctl, and is also disabled on routes with "mtu lock". In those cases, we shouldn't set the DF bit. This patch makes setting the DF bit conditional on the route's MTU locking state. This issue seems to be older than git history. Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-13net/ipv4: defensive cipso option parsingStefan Nuernberger
commit 076ed3da0c9b2f88d9157dbe7044a45641ae369e upstream. commit 40413955ee26 ("Cipso: cipso_v4_optptr enter infinite loop") fixed a possible infinite loop in the IP option parsing of CIPSO. The fix assumes that ip_options_compile filtered out all zero length options and that no other one-byte options beside IPOPT_END and IPOPT_NOOP exist. While this assumption currently holds true, add explicit checks for zero length and invalid length options to be safe for the future. Even though ip_options_compile should have validated the options, the introduction of new one-byte options can still confuse this code without the additional checks. Signed-off-by: Stefan Nuernberger <snu@amazon.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Simon Veith <sveith@amazon.de> Cc: stable@vger.kernel.org Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-04net: drop skb on failure in ip_check_defrag()Cong Wang
[ Upstream commit 7de414a9dd91426318df7b63da024b2b07e53df5 ] Most callers of pskb_trim_rcsum() simply drop the skb when it fails, however, ip_check_defrag() still continues to pass the skb up to stack. This is suspicious. In ip_check_defrag(), after we learn the skb is an IP fragment, passing the skb to callers makes no sense, because callers expect fragments are defrag'ed on success. So, dropping the skb when we can't defrag it is reasonable. Note, prior to commit 88078d98d1bb, this is not a big problem as checksum will be fixed up anyway. After it, the checksum is not correct on failure. Found this during code review. Fixes: 88078d98d1bb ("net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends") Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-04Revert "net: simplify sock_poll_wait"Karsten Graul
[ Upstream commit 89ab066d4229acd32e323f1569833302544a4186 ] This reverts commit dd979b4df817e9976f18fb6f9d134d6bc4a3c317. This broke tcp_poll for SMC fallback: An AF_SMC socket establishes an internal TCP socket for the initial handshake with the remote peer. Whenever the SMC connection can not be established this TCP socket is used as a fallback. All socket operations on the SMC socket are then forwarded to the TCP socket. In case of poll, the file->private_data pointer references the SMC socket because the TCP socket has no file assigned. This causes tcp_poll to wait on the wrong socket. Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-04net: udp: fix handling of CHECKSUM_COMPLETE packetsSean Tranchetti
[ Upstream commit db4f1be3ca9b0ef7330763d07bf4ace83ad6f913 ] Current handling of CHECKSUM_COMPLETE packets by the UDP stack is incorrect for any packet that has an incorrect checksum value. udp4/6_csum_init() will both make a call to __skb_checksum_validate_complete() to initialize/validate the csum field when receiving a CHECKSUM_COMPLETE packet. When this packet fails validation, skb->csum will be overwritten with the pseudoheader checksum so the packet can be fully validated by software, but the skb->ip_summed value will be left as CHECKSUM_COMPLETE so that way the stack can later warn the user about their hardware spewing bad checksums. Unfortunately, leaving the SKB in this state can cause problems later on in the checksum calculation. Since the the packet is still marked as CHECKSUM_COMPLETE, udp_csum_pull_header() will SUBTRACT the checksum of the UDP header from skb->csum instead of adding it, leaving us with a garbage value in that field. Once we try to copy the packet to userspace in the udp4/6_recvmsg(), we'll make a call to skb_copy_and_csum_datagram_msg() to checksum the packet data and add it in the garbage skb->csum value to perform our final validation check. Since the value we're validating is not the proper checksum, it's possible that the folded value could come out to 0, causing us not to drop the packet. Instead, we believe that the packet was checksummed incorrectly by hardware since skb->ip_summed is still CHECKSUM_COMPLETE, and we attempt to warn the user with netdev_rx_csum_fault(skb->dev); Unfortunately, since this is the UDP path, skb->dev has been overwritten by skb->dev_scratch and is no longer a valid pointer, so we end up reading invalid memory. This patch addresses this problem in two ways: 1) Do not use the dev pointer when calling netdev_rx_csum_fault() from skb_copy_and_csum_datagram_msg(). Since this gets called from the UDP path where skb->dev has been overwritten, we have no way of knowing if the pointer is still valid. Also for the sake of consistency with the other uses of netdev_rx_csum_fault(), don't attempt to call it if the packet was checksummed by software. 2) Add better CHECKSUM_COMPLETE handling to udp4/6_csum_init(). If we receive a packet that's CHECKSUM_COMPLETE that fails verification (i.e. skb->csum_valid == 0), check who performed the calculation. It's possible that the checksum was done in software by the network stack earlier (such as Netfilter's CONNTRACK module), and if that says the checksum is bad, we can drop the packet immediately instead of waiting until we try and copy it to userspace. Otherwise, we need to mark the SKB as CHECKSUM_NONE, since the skb->csum field no longer contains the full packet checksum after the call to __skb_checksum_validate_complete(). Fixes: e6afc8ace6dd ("udp: remove headers from UDP packets before queueing") Fixes: c84d949057ca ("udp: copy skb->truesize in the first cache line") Cc: Sam Kumar <samanthakumar@google.com> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Sean Tranchetti <stranche@codeaurora.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-17net: ipmr: fix unresolved entry dumpsNikolay Aleksandrov
If the skb space ends in an unresolved entry while dumping we'll miss some unresolved entries. The reason is due to zeroing the entry counter between dumping resolved and unresolved mfc entries. We should just keep counting until the whole table is dumped and zero when we move to the next as we have a separate table counter. Reported-by: Colin Ian King <colin.king@canonical.com> Fixes: 8fb472c09b9d ("ipmr: improve hash scalability") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-10net: ipv4: don't let PMTU updates increase route MTUSabrina Dubroca
When an MTU update with PMTU smaller than net.ipv4.route.min_pmtu is received, we must clamp its value. However, we can receive a PMTU exception with PMTU < old_mtu < ip_rt_min_pmtu, which would lead to an increase in PMTU. To fix this, take the smallest of the old MTU and ip_rt_min_pmtu. Before this patch, in case of an update, the exception's MTU would always change. Now, an exception can have only its lock flag updated, but not the MTU, so we need to add a check on locking to the following "is this exception getting updated, or close to expiring?" test. Fixes: d52e5a7e7ca4 ("ipv4: lock mtu in fnhe when received PMTU < net.ipv4.route.min_pmtu") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-10net: ipv4: update fnhe_pmtu when first hop's MTU changesSabrina Dubroca
Since commit 5aad1de5ea2c ("ipv4: use separate genid for next hop exceptions"), exceptions get deprecated separately from cached routes. In particular, administrative changes don't clear PMTU anymore. As Stefano described in commit e9fa1495d738 ("ipv6: Reflect MTU changes on PMTU of exceptions for MTU-less routes"), the PMTU discovered before the local MTU change can become stale: - if the local MTU is now lower than the PMTU, that PMTU is now incorrect - if the local MTU was the lowest value in the path, and is increased, we might discover a higher PMTU Similarly to what commit e9fa1495d738 did for IPv6, update PMTU in those cases. If the exception was locked, the discovered PMTU was smaller than the minimal accepted PMTU. In that case, if the new local MTU is smaller than the current PMTU, let PMTU discovery figure out if locking of the exception is still needed. To do this, we need to know the old link MTU in the NETDEV_CHANGEMTU notifier. By the time the notifier is called, dev->mtu has been changed. This patch adds the old MTU as additional information in the notifier structure, and a new call_netdevice_notifiers_u32() function. Fixes: 5aad1de5ea2c ("ipv4: use separate genid for next hop exceptions") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-07udp: Unbreak modules that rely on external __skb_recv_udp() availabilityJiri Kosina
Commit 2276f58ac589 ("udp: use a separate rx queue for packet reception") turned static inline __skb_recv_udp() from being a trivial helper around __skb_recv_datagram() into a UDP specific implementaion, making it EXPORT_SYMBOL_GPL() at the same time. There are external modules that got broken by __skb_recv_udp() not being visible to them. Let's unbreak them by making __skb_recv_udp EXPORT_SYMBOL(). Rationale (one of those) why this is actually "technically correct" thing to do: __skb_recv_udp() used to be an inline wrapper around __skb_recv_datagram(), which itself (still, and correctly so, I believe) is EXPORT_SYMBOL(). Cc: Paolo Abeni <pabeni@redhat.com> Cc: Eric Dumazet <edumazet@google.com> Fixes: 2276f58ac589 ("udp: use a separate rx queue for packet reception") Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02ipv4: fix use-after-free in ip_cmsg_recv_dstaddr()Eric Dumazet
Caching ip_hdr(skb) before a call to pskb_may_pull() is buggy, do not do it. Fixes: 2efd4fca703a ("ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02inet: make sure to grab rcu_read_lock before using ireq->ireq_optEric Dumazet
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>
2018-10-01Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec Steffen Klassert says: ==================== pull request (net): ipsec 2018-10-01 1) Validate address prefix lengths in the xfrm selector, otherwise we may hit undefined behaviour in the address matching functions if the prefix is too big for the given address family. 2) Fix skb leak on local message size errors. From Thadeu Lima de Souza Cascardo. 3) We currently reset the transport header back to the network header after a transport mode transformation is applied. This leads to an incorrect transport header when multiple transport mode transformations are applied. Reset the transport header only after all transformations are already applied to fix this. From Sowmini Varadhan. 4) We only support one offloaded xfrm, so reset crypto_done after the first transformation in xfrm_input(). Otherwise we may call the wrong input method for subsequent transformations. From Sowmini Varadhan. 5) Fix NULL pointer dereference when skb_dst_force clears the dst_entry. skb_dst_force does not really force a dst refcount anymore, it might clear it instead. xfrm code did not expect this, add a check to not dereference skb_dst() if it was cleared by skb_dst_force. 6) Validate xfrm template mode, otherwise we can get a stack-out-of-bounds read in xfrm_state_find. From Sean Tranchetti. Please pull or let me know if there are problems. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-01tcp/dccp: fix lockdep issue when SYN is backloggedEric Dumazet
In normal SYN processing, packets are handled without listener lock and in RCU protected ingress path. But syzkaller is known to be able to trick us and SYN packets might be processed in process context, after being queued into socket backlog. In commit 06f877d613be ("tcp/dccp: fix other lockdep splats accessing ireq_opt") I made a very stupid fix, that happened to work mostly because of the regular path being RCU protected. Really the thing protecting ireq->ireq_opt is RCU read lock, and the pseudo request refcnt is not relevant. This patch extends what I did in commit 449809a66c1d ("tcp/dccp: block BH for SYN processing") by adding an extra rcu_read_{lock|unlock} pair in the paths that might be taken when processing SYN from socket backlog (thus possibly in process context) Fixes: 06f877d613be ("tcp/dccp: fix other lockdep splats accessing ireq_opt") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26net-tcp: /proc/sys/net/ipv4/tcp_probe_interval is a u32 not intMaciej Żenczykowski
(fix documentation and sysctl access to treat it as such) Tested: # zcat /proc/config.gz | egrep ^CONFIG_HZ CONFIG_HZ_1000=y CONFIG_HZ=1000 # echo $[(1<<32)/1000 + 1] | tee /proc/sys/net/ipv4/tcp_probe_interval 4294968 tee: /proc/sys/net/ipv4/tcp_probe_interval: Invalid argument # echo $[(1<<32)/1000] | tee /proc/sys/net/ipv4/tcp_probe_interval 4294967 # echo 0 | tee /proc/sys/net/ipv4/tcp_probe_interval # echo -1 | tee /proc/sys/net/ipv4/tcp_probe_interval -1 tee: /proc/sys/net/ipv4/tcp_probe_interval: Invalid argument Signed-off-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-24ip_tunnel: be careful when accessing the inner headerPaolo Abeni
Cong noted that we need the same checks introduced by commit 76c0ddd8c3a6 ("ip6_tunnel: be careful when accessing the inner header") even for ipv4 tunnels. Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.") Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-16udp4: fix IP_CMSG_CHECKSUM for connected socketsPaolo Abeni
commit 2abb7cdc0dc8 ("udp: Add support for doing checksum unnecessary conversion") left out the early demux path for connected sockets. As a result IP_CMSG_CHECKSUM gives wrong values for such socket when GRO is not enabled/available. This change addresses the issue by moving the csum conversion to a common helper and using such helper in both the default and the early demux rx path. Fixes: 2abb7cdc0dc8 ("udp: Add support for doing checksum unnecessary conversion") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-13gso_segment: Reset skb->mac_len after modifying network headerToke Høiland-Jørgensen
When splitting a GSO segment that consists of encapsulated packets, the skb->mac_len of the segments can end up being set wrong, causing packet drops in particular when using act_mirred and ifb interfaces in combination with a qdisc that splits GSO packets. This happens because at the time skb_segment() is called, network_header will point to the inner header, throwing off the calculation in skb_reset_mac_len(). The network_header is subsequently adjust by the outer IP gso_segment handlers, but they don't set the mac_len. Fix this by adding skb_reset_mac_len() calls to both the IPv4 and IPv6 gso_segment handlers, after they modify the network_header. Many thanks to Eric Dumazet for his help in identifying the cause of the bug. Acked-by: Dave Taht <dave.taht@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-11erspan: fix error handling for erspan tunnelHaishuang Yan
When processing icmp unreachable message for erspan tunnel, tunnel id should be erspan_net_id instead of ipgre_net_id. Fixes: 84e54fe0a5ea ("gre: introduce native tunnel support for ERSPAN") Cc: William Tu <u9012063@gmail.com> Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Acked-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-11erspan: return PACKET_REJECT when the appropriate tunnel is not foundHaishuang Yan
If erspan tunnel hasn't been established, we'd better send icmp port unreachable message after receive erspan packets. Fixes: 84e54fe0a5ea ("gre: introduce native tunnel support for ERSPAN") Cc: William Tu <u9012063@gmail.com> Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Acked-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-11tcp: rate limit synflood warnings furtherWillem de Bruijn
Convert pr_info to net_info_ratelimited to limit the total number of synflood warnings. Commit 946cedccbd73 ("tcp: Change possible SYN flooding messages") rate limits synflood warnings to one per listener. Workloads that open many listener sockets can still see a high rate of log messages. Syzkaller is one frequent example. Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nfDavid S. Miller
Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for you net tree: 1) Remove duplicated include at the end of UDP conntrack, from Yue Haibing. 2) Restore conntrack dependency on xt_cluster, from Martin Willi. 3) Fix splat with GSO skbs from the checksum target, from Florian Westphal. 4) Rework ct timeout support, the template strategy to attach custom timeouts is not correct since it will not work in conjunction with conntrack zones and we have a possible free after use when removing the rule due to missing refcounting. To fix these problems, do not use conntrack template at all and set custom timeout on the already valid conntrack object. This fix comes with a preparation patch to simplify timeout adjustment by initializating the first position of the timeout array for all of the existing trackers. Patchset from Florian Westphal. 5) Fix missing dependency on from IPv4 chain NAT type, from Florian. 6) Release chain reference counter from the flush path, from Taehee Yoo. 7) After flushing an iptables ruleset, conntrack hooks are unregistered and entries are left stale to be cleaned up by the timeout garbage collector. No TCP tracking is done on established flows by this time. If ruleset is reloaded, then hooks are registered again and TCP tracking is restored, which considers packets to be invalid. Clear window tracking to exercise TCP flow pickup from the middle given that history is lost for us. Again from Florian. 8) Fix crash from netlink interface with CONFIG_NF_CONNTRACK_TIMEOUT=y and CONFIG_NF_CT_NETLINK_TIMEOUT=n. 9) Broken CT target due to returning incorrect type from ctnl_timeout_find_get(). 10) Solve conntrack clash on NF_REPEAT verdicts too, from Michal Vaner. 11) Missing conversion of hashlimit sysctl interface to new API, from Cong Wang. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-09ip: frags: fix crash in ip_do_fragment()Taehee Yoo
A kernel crash occurrs when defragmented packet is fragmented in ip_do_fragment(). In defragment routine, skb_orphan() is called and skb->ip_defrag_offset is set. but skb->sk and skb->ip_defrag_offset are same union member. so that frag->sk is not NULL. Hence crash occurrs in skb->sk check routine in ip_do_fragment() when defragmented packet is fragmented. test commands: %iptables -t nat -I POSTROUTING -j MASQUERADE %hping3 192.168.4.2 -s 1000 -p 2000 -d 60000 splat looks like: [ 261.069429] kernel BUG at net/ipv4/ip_output.c:636! [ 261.075753] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 261.083854] CPU: 1 PID: 1349 Comm: hping3 Not tainted 4.19.0-rc2+ #3 [ 261.100977] RIP: 0010:ip_do_fragment+0x1613/0x2600 [ 261.106945] Code: e8 e2 38 e3 fe 4c 8b 44 24 18 48 8b 74 24 08 e9 92 f6 ff ff 80 3c 02 00 0f 85 da 07 00 00 48 8b b5 d0 00 00 00 e9 25 f6 ff ff <0f> 0b 0f 0b 44 8b 54 24 58 4c 8b 4c 24 18 4c 8b 5c 24 60 4c 8b 6c [ 261.127015] RSP: 0018:ffff8801031cf2c0 EFLAGS: 00010202 [ 261.134156] RAX: 1ffff1002297537b RBX: ffffed0020639e6e RCX: 0000000000000004 [ 261.142156] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880114ba9bd8 [ 261.150157] RBP: ffff880114ba8a40 R08: ffffed0022975395 R09: ffffed0022975395 [ 261.158157] R10: 0000000000000001 R11: ffffed0022975394 R12: ffff880114ba9ca4 [ 261.166159] R13: 0000000000000010 R14: ffff880114ba9bc0 R15: dffffc0000000000 [ 261.174169] FS: 00007fbae2199700(0000) GS:ffff88011b400000(0000) knlGS:0000000000000000 [ 261.183012] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 261.189013] CR2: 00005579244fe000 CR3: 0000000119bf4000 CR4: 00000000001006e0 [ 261.198158] Call Trace: [ 261.199018] ? dst_output+0x180/0x180 [ 261.205011] ? save_trace+0x300/0x300 [ 261.209018] ? ip_copy_metadata+0xb00/0xb00 [ 261.213034] ? sched_clock_local+0xd4/0x140 [ 261.218158] ? kill_l4proto+0x120/0x120 [nf_conntrack] [ 261.223014] ? rt_cpu_seq_stop+0x10/0x10 [ 261.227014] ? find_held_lock+0x39/0x1c0 [ 261.233008] ip_finish_output+0x51d/0xb50 [ 261.237006] ? ip_fragment.constprop.56+0x220/0x220 [ 261.243011] ? nf_ct_l4proto_register_one+0x5b0/0x5b0 [nf_conntrack] [ 261.250152] ? rcu_is_watching+0x77/0x120 [ 261.255010] ? nf_nat_ipv4_out+0x1e/0x2b0 [nf_nat_ipv4] [ 261.261033] ? nf_hook_slow+0xb1/0x160 [ 261.265007] ip_output+0x1c7/0x710 [ 261.269005] ? ip_mc_output+0x13f0/0x13f0 [ 261.273002] ? __local_bh_enable_ip+0xe9/0x1b0 [ 261.278152] ? ip_fragment.constprop.56+0x220/0x220 [ 261.282996] ? nf_hook_slow+0xb1/0x160 [ 261.287007] raw_sendmsg+0x21f9/0x4420 [ 261.291008] ? dst_output+0x180/0x180 [ 261.297003] ? sched_clock_cpu+0x126/0x170 [ 261.301003] ? find_held_lock+0x39/0x1c0 [ 261.306155] ? stop_critical_timings+0x420/0x420 [ 261.311004] ? check_flags.part.36+0x450/0x450 [ 261.315005] ? _raw_spin_unlock_irq+0x29/0x40 [ 261.320995] ? _raw_spin_unlock_irq+0x29/0x40 [ 261.326142] ? cyc2ns_read_end+0x10/0x10 [ 261.330139] ? raw_bind+0x280/0x280 [ 261.334138] ? sched_clock_cpu+0x126/0x170 [ 261.338995] ? check_flags.part.36+0x450/0x450 [ 261.342991] ? __lock_acquire+0x4500/0x4500 [ 261.348994] ? inet_sendmsg+0x11c/0x500 [ 261.352989] ? dst_output+0x180/0x180 [ 261.357012] inet_sendmsg+0x11c/0x500 [ ... ] v2: - clear skb->sk at reassembly routine.(Eric Dumarzet) Fixes: fa0f527358bd ("ip: use rb trees for IP frag queue.") Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Taehee Yoo <ap420073@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-07tcp: really ignore MSG_ZEROCOPY if no SO_ZEROCOPYVincent Whitchurch
According to the documentation in msg_zerocopy.rst, the SO_ZEROCOPY flag was introduced because send(2) ignores unknown message flags and any legacy application which was accidentally passing the equivalent of MSG_ZEROCOPY earlier should not see any new behaviour. Before commit f214f915e7db ("tcp: enable MSG_ZEROCOPY"), a send(2) call which passed the equivalent of MSG_ZEROCOPY without setting SO_ZEROCOPY would succeed. However, after that commit, it fails with -ENOBUFS. So it appears that the SO_ZEROCOPY flag fails to fulfill its intended purpose. Fix it. Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-04xfrm: reset transport header back to network header after all input ↵Sowmini Varadhan
transforms ahave been applied A policy may have been set up with multiple transforms (e.g., ESP and ipcomp). In this situation, the ingress IPsec processing iterates in xfrm_input() and applies each transform in turn, processing the nexthdr to find any additional xfrm that may apply. This patch resets the transport header back to network header only after the last transformation so that subsequent xfrms can find the correct transport header. Fixes: 7785bba299a8 ("esp: Add a software GRO codepath") Suggested-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2018-09-02igmp: fix incorrect unsolicit report count after link down and upHangbin Liu
After link down and up, i.e. when call ip_mc_up(), we doesn't init im->unsolicit_count. So after igmp_timer_expire(), we will not start timer again and only send one unsolicit report at last. Fix it by initializing im->unsolicit_count in igmp_group_added(), so we can respect igmp robustness value. Fixes: 24803f38a5c0b ("igmp: do not remove igmp souce list info when set link down") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-02igmp: fix incorrect unsolicit report count when join groupHangbin Liu
We should not start timer if im->unsolicit_count equal to 0 after decrease. Or we will send one more unsolicit report message. i.e. 3 instead of 2 by default. Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-31tcp: do not restart timewait timer on rst receptionFlorian Westphal
RFC 1337 says: ''Ignore RST segments in TIME-WAIT state. If the 2 minute MSL is enforced, this fix avoids all three hazards.'' So with net.ipv4.tcp_rfc1337=1, expected behaviour is to have TIME-WAIT sk expire rather than removing it instantly when a reset is received. However, Linux will also re-start the TIME-WAIT timer. This causes connect to fail when tying to re-use ports or very long delays (until syn retry interval exceeds MSL). packetdrill test case: // Demonstrate bogus rearming of TIME-WAIT timer in rfc1337 mode. `sysctl net.ipv4.tcp_rfc1337=1` 0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 0.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 0.000 bind(3, ..., ...) = 0 0.000 listen(3, 1) = 0 0.100 < S 0:0(0) win 29200 <mss 1460,nop,nop,sackOK,nop,wscale 7> 0.100 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 7> 0.200 < . 1:1(0) ack 1 win 257 0.200 accept(3, ..., ...) = 4 // Receive first segment 0.310 < P. 1:1001(1000) ack 1 win 46 // Send one ACK 0.310 > . 1:1(0) ack 1001 // read 1000 byte 0.310 read(4, ..., 1000) = 1000 // Application writes 100 bytes 0.350 write(4, ..., 100) = 100 0.350 > P. 1:101(100) ack 1001 // ACK 0.500 < . 1001:1001(0) ack 101 win 257 // close the connection 0.600 close(4) = 0 0.600 > F. 101:101(0) ack 1001 win 244 // Our side is in FIN_WAIT_1 & waits for ack to fin 0.7 < . 1001:1001(0) ack 102 win 244 // Our side is in FIN_WAIT_2 with no outstanding data. 0.8 < F. 1001:1001(0) ack 102 win 244 0.8 > . 102:102(0) ack 1002 win 244 // Our side is now in TIME_WAIT state, send ack for fin. 0.9 < F. 1002:1002(0) ack 102 win 244 0.9 > . 102:102(0) ack 1002 win 244 // Peer reopens with in-window SYN: 1.000 < S 1000:1000(0) win 9200 <mss 1460,nop,nop,sackOK,nop,wscale 7> // Therefore, reply with ACK. 1.000 > . 102:102(0) ack 1002 win 244 // Peer sends RST for this ACK. Normally this RST results // in tw socket removal, but rfc1337=1 setting prevents this. 1.100 < R 1002:1002(0) win 244 // second syn. Due to rfc1337=1 expect another pure ACK. 31.0 < S 1000:1000(0) win 9200 <mss 1460,nop,nop,sackOK,nop,wscale 7> 31.0 > . 102:102(0) ack 1002 win 244 // .. and another RST from peer. 31.1 < R 1002:1002(0) win 244 31.2 `echo no timer restart;ss -m -e -a -i -n -t -o state TIME-WAIT` // third syn after one minute. Time-Wait socket should have expired by now. 63.0 < S 1000:1000(0) win 9200 <mss 1460,nop,nop,sackOK,nop,wscale 7> // so we expect a syn-ack & 3whs to proceed from here on. 63.0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 7> Without this patch, 'ss' shows restarts of tw timer and last packet is thus just another pure ack, more than one minute later. This restores the original code from commit 283fd6cf0be690a83 ("Merge in ANK networking jumbo patch") in netdev-vger-cvs.git . For some reason the else branch was removed/lost in 1f28b683339f7 ("Merge in TCP/UDP optimizations and [..]") and timer restart became unconditional. Reported-by: Michal Tesar <mtesar@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-31netfilter: kconfig: nat related expression depend on nftables coreFlorian Westphal
NF_TABLES_IPV4 is now boolean so it is possible to set NF_TABLES=m NF_TABLES_IPV4=y NFT_CHAIN_NAT_IPV4=y which causes: nft_chain_nat_ipv4.c:(.text+0x6d): undefined reference to `nft_do_chain' Wrap NFT_CHAIN_NAT_IPV4 and related nat expressions with NF_TABLES to restore the dependency. Reported-by: Randy Dunlap <rdunlap@infradead.org> Fixes: 02c7b25e5f54 ("netfilter: nf_tables: build-in filter chain type") Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-08-27erspan: set erspan_ver to 1 by default when adding an erspan devXin Long
After erspan_ver is introudced, if erspan_ver is not set in iproute, its value will be left 0 by default. Since Commit 02f99df1875c ("erspan: fix invalid erspan version."), it has broken the traffic due to the version check in erspan_xmit if users are not aware of 'erspan_ver' param, like using an old version of iproute. To fix this compatibility problem, it sets erspan_ver to 1 by default when adding an erspan dev in erspan_setup. Note that we can't do it in ipgre_netlink_parms, as this function is also used by ipgre_changelink. Fixes: 02f99df1875c ("erspan: fix invalid erspan version.") Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-22tcp_bbr: apply PROBE_RTT cwnd cap even if acked==0Kevin Yang
This commit fixes a corner case where TCP BBR would enter PROBE_RTT mode but not reduce its cwnd. If a TCP receiver ACKed less than one full segment, the number of delivered/acked packets was 0, so that bbr_set_cwnd() would short-circuit and exit early, without cutting cwnd to the value we want for PROBE_RTT. The fix is to instead make sure that even when 0 full packets are ACKed, we do apply all the appropriate caps, including the cap that applies in PROBE_RTT mode. Fixes: 0f8782ea1497 ("tcp_bbr: add BBR congestion control") Signed-off-by: Kevin Yang <yyd@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-22tcp_bbr: in restart from idle, see if we should exit PROBE_RTTKevin Yang
This patch fix the case where BBR does not exit PROBE_RTT mode when it restarts from idle. When BBR restarts from idle and if BBR is in PROBE_RTT mode, BBR should check if it's time to exit PROBE_RTT. If yes, then BBR should exit PROBE_RTT mode and restore the cwnd to its full value. Fixes: 0f8782ea1497 ("tcp_bbr: add BBR congestion control") Signed-off-by: Kevin Yang <yyd@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-22tcp_bbr: add bbr_check_probe_rtt_done() helperKevin Yang
This patch add a helper function bbr_check_probe_rtt_done() to 1. check the condition to see if bbr should exit probe_rtt mode; 2. process the logic of exiting probe_rtt mode. Fixes: 0f8782ea1497 ("tcp_bbr: add BBR congestion control") Signed-off-by: Kevin Yang <yyd@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.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 Dumazet
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>
2018-08-19ip_vti: fix a null pointer deferrence when create vti fallback tunnelHaishuang Yan
After set fb_tunnels_only_for_init_net to 1, the itn->fb_tunnel_dev will be NULL and will cause following crash: [ 2742.849298] BUG: unable to handle kernel NULL pointer dereference at 0000000000000941 [ 2742.851380] PGD 800000042c21a067 P4D 800000042c21a067 PUD 42aaed067 PMD 0 [ 2742.852818] Oops: 0002 [#1] SMP PTI [ 2742.853570] CPU: 7 PID: 2484 Comm: unshare Kdump: loaded Not tainted 4.18.0-rc8+ #2 [ 2742.855163] Hardware name: Fedora Project OpenStack Nova, BIOS seabios-1.7.5-11.el7 04/01/2014 [ 2742.856970] RIP: 0010:vti_init_net+0x3a/0x50 [ip_vti] [ 2742.858034] Code: 90 83 c0 48 c7 c2 20 a1 83 c0 48 89 fb e8 6e 3b f6 ff 85 c0 75 22 8b 0d f4 19 00 00 48 8b 93 00 14 00 00 48 8b 14 ca 48 8b 12 <c6> 82 41 09 00 00 04 c6 82 38 09 00 00 45 5b c3 66 0f 1f 44 00 00 [ 2742.861940] RSP: 0018:ffff9be28207fde0 EFLAGS: 00010246 [ 2742.863044] RAX: 0000000000000000 RBX: ffff8a71ebed4980 RCX: 0000000000000013 [ 2742.864540] RDX: 0000000000000000 RSI: 0000000000000013 RDI: ffff8a71ebed4980 [ 2742.866020] RBP: ffff8a71ea717000 R08: ffffffffc083903c R09: ffff8a71ea717000 [ 2742.867505] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8a71ebed4980 [ 2742.868987] R13: 0000000000000013 R14: ffff8a71ea5b49c0 R15: 0000000000000000 [ 2742.870473] FS: 00007f02266c9740(0000) GS:ffff8a71ffdc0000(0000) knlGS:0000000000000000 [ 2742.872143] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2742.873340] CR2: 0000000000000941 CR3: 000000042bc20006 CR4: 00000000001606e0 [ 2742.874821] Call Trace: [ 2742.875358] ops_init+0x38/0xf0 [ 2742.876078] setup_net+0xd9/0x1f0 [ 2742.876789] copy_net_ns+0xb7/0x130 [ 2742.877538] create_new_namespaces+0x11a/0x1d0 [ 2742.878525] unshare_nsproxy_namespaces+0x55/0xa0 [ 2742.879526] ksys_unshare+0x1a7/0x330 [ 2742.880313] __x64_sys_unshare+0xe/0x20 [ 2742.881131] do_syscall_64+0x5b/0x180 [ 2742.881933] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reproduce: echo 1 > /proc/sys/net/core/fb_tunnels_only_for_init_net modprobe ip_vti unshare -n Fixes: 79134e6ce2c9 ("net: do not create fallback tunnels for non-default namespaces") Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-16tcp, ulp: fix leftover icsk_ulp_ops preventing sock from reattachDaniel Borkmann
I found that in BPF sockmap programs once we either delete a socket from the map or we updated a map slot and the old socket was purged from the map that these socket can never get reattached into a map even though their related psock has been dropped entirely at that point. Reason is that tcp_cleanup_ulp() leaves the old icsk->icsk_ulp_ops intact, so that on the next tcp_set_ulp_id() the kernel returns an -EEXIST thinking there is still some active ULP attached. BPF sockmap is the only one that has this issue as the other user, kTLS, only calls tcp_cleanup_ulp() from tcp_v4_destroy_sock() whereas sockmap semantics allow dropping the socket from the map with all related psock state being cleaned up. Fixes: 1aa12bdf1bfb ("bpf: sockmap, add sock close() hook to remove socks") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-16tcp, ulp: add alias for all ulp modulesDaniel Borkmann
Lets not turn the TCP ULP lookup into an arbitrary module loader as we only intend to load ULP modules through this mechanism, not other unrelated kernel modules: [root@bar]# cat foo.c #include <sys/types.h> #include <sys/socket.h> #include <linux/tcp.h> #include <linux/in.h> int main(void) { int sock = socket(PF_INET, SOCK_STREAM, 0); setsockopt(sock, IPPROTO_TCP, TCP_ULP, "sctp", sizeof("sctp")); return 0; } [root@bar]# gcc foo.c -O2 -Wall [root@bar]# lsmod | grep sctp [root@bar]# ./a.out [root@bar]# lsmod | grep sctp sctp 1077248 4 libcrc32c 16384 3 nf_conntrack,nf_nat,sctp [root@bar]# Fix it by adding module alias to TCP ULP modules, so probing module via request_module() will be limited to tcp-ulp-[name]. The existing modules like kTLS will load fine given tcp-ulp-tls alias, but others will fail to load: [root@bar]# lsmod | grep sctp [root@bar]# ./a.out [root@bar]# lsmod | grep sctp [root@bar]# Sockmap is not affected from this since it's either built-in or not. Fixes: 734942cc4ea6 ("tcp: ULP infrastructure") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf-next 2018-08-13 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Add driver XDP support for veth. This can be used in conjunction with redirect of another XDP program e.g. sitting on NIC so the xdp_frame can be forwarded to the peer veth directly without modification, from Toshiaki. 2) Add a new BPF map type REUSEPORT_SOCKARRAY and prog type SK_REUSEPORT in order to provide more control and visibility on where a SO_REUSEPORT sk should be located, and the latter enables to directly select a sk from the bpf map. This also enables map-in-map for application migration use cases, from Martin. 3) Add a new BPF helper bpf_skb_ancestor_cgroup_id() that returns the id of cgroup v2 that is the ancestor of the cgroup associated with the skb at the ancestor_level, from Andrey. 4) Implement BPF fs map pretty-print support based on BTF data for regular hash table and LRU map, from Yonghong. 5) Decouple the ability to attach BTF for a map from the key and value pretty-printer in BPF fs, and enable further support of BTF for maps for percpu and LPM trie, from Daniel. 6) Implement a better BPF sample of using XDP's CPU redirect feature for load balancing SKB processing to remote CPU. The sample implements the same XDP load balancing as Suricata does which is symmetric hash based on IP and L4 protocol, from Jesper. 7) Revert adding NULL pointer check with WARN_ON_ONCE() in __xdp_return()'s critical path as it is ensured that the allocator is present, from Björn. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11ip: process in-order fragments efficientlyPeter Oskolkov
This patch changes the runtime behavior of IP defrag queue: incoming in-order fragments are added to the end of the current list/"run" of in-order fragments at the tail. On some workloads, UDP stream performance is substantially improved: RX: ./udp_stream -F 10 -T 2 -l 60 TX: ./udp_stream -c -H <host> -F 10 -T 5 -l 60 with this patchset applied on a 10Gbps receiver: throughput=9524.18 throughput_units=Mbit/s upstream (net-next): throughput=4608.93 throughput_units=Mbit/s Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Peter Oskolkov <posk@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11ip: add helpers to process in-order fragments faster.Peter Oskolkov
This patch introduces several helper functions/macros that will be used in the follow-up patch. No runtime changes yet. The new logic (fully implemented in the second patch) is as follows: * Nodes in the rb-tree will now contain not single fragments, but lists of consecutive fragments ("runs"). * At each point in time, the current "active" run at the tail is maintained/tracked. Fragments that arrive in-order, adjacent to the previous tail fragment, are added to this tail run without triggering the re-balancing of the rb-tree. * If a fragment arrives out of order with the offset _before_ the tail run, it is inserted into the rb-tree as a single fragment. * If a fragment arrives after the current tail fragment (with a gap), it starts a new "tail" run, as is inserted into the rb-tree at the end as the head of the new run. skb->cb is used to store additional information needed here (suggested by Eric Dumazet). Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Peter Oskolkov <posk@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11tcp: avoid resetting ACK timer upon receiving packet with ECN CWR flagYuchung Cheng
Previously commit 9aee40006190 ("tcp: ack immediately when a cwr packet arrives") calls tcp_enter_quickack_mode to force sending two immediate ACKs upon receiving a packet w/ CWR flag. The side effect is it'll also reset the delayed ACK timer and interactive session tracking. This patch removes that side effect by using the new ACK_NOW flag to force an immmediate ACK. Packetdrill to demonstrate: 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 setsockopt(3, SOL_TCP, TCP_CONGESTION, "dctcp", 5) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1) = 0 +0 < [ect0] SEW 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7> +0 > SE. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8> +.1 < [ect0] . 1:1(0) ack 1 win 257 +0 accept(3, ..., ...) = 4 +0 < [ect0] . 1:1001(1000) ack 1 win 257 +0 > [ect01] . 1:1(0) ack 1001 +0 write(4, ..., 1) = 1 +0 > [ect01] P. 1:2(1) ack 1001 +0 < [ect0] . 1001:2001(1000) ack 2 win 257 +0 write(4, ..., 1) = 1 +0 > [ect01] P. 2:3(1) ack 2001 +0 < [ect0] . 2001:3001(1000) ack 3 win 257 +0 < [ect0] . 3001:4001(1000) ack 3 win 257 // Ack delayed ... +.01 < [ce] P. 4001:4501(500) ack 3 win 257 +0 > [ect01] . 3:3(0) ack 4001 +0 > [ect01] E. 3:3(0) ack 4501 +.001 read(4, ..., 4500) = 4500 +0 write(4, ..., 1) = 1 +0 > [ect01] PE. 3:4(1) ack 4501 win 100 +.01 < [ect0] W. 4501:5501(1000) ack 4 win 257 // No delayed ACK on CWR flag +0 > [ect01] . 4:4(0) ack 5501 +.31 < [ect0] . 5501:6501(1000) ack 4 win 257 +0 > [ect01] . 4:4(0) ack 6501 Fixes: 9aee40006190 ("tcp: ack immediately when a cwr packet arrives") Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11tcp: always ACK immediately on hole repairsYuchung Cheng
RFC 5681 sec 4.2: To provide feedback to senders recovering from losses, the receiver SHOULD send an immediate ACK when it receives a data segment that fills in all or part of a gap in the sequence space. When a gap is partially filled, __tcp_ack_snd_check already checks the out-of-order queue and correctly send an immediate ACK. However when a gap is fully filled, the previous implementation only resets pingpong mode which does not guarantee an immediate ACK because the quick ACK counter may be zero. This patch addresses this issue by marking the one-time immediate ACK flag instead. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11tcp: avoid resetting ACK timer in DCTCPYuchung Cheng
The recent fix of acking immediately in DCTCP on CE status change has an undesirable side-effect: it also resets TCP ack timer and disables pingpong mode (interactive session). But the CE status change has nothing to do with them. This patch addresses that by using the new one-time immediate ACK flag instead of calling tcp_enter_quickack_mode(). Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11tcp: mandate a one-time immediate ACKYuchung Cheng
Add a new flag to indicate a one-time immediate ACK. This flag is occasionaly set under specific TCP protocol states in addition to the more common quickack mechanism for interactive application. In several cases in the TCP code we want to force an immediate ACK but do not want to call tcp_enter_quickack_mode() because we do not want to forget the icsk_ack.pingpong or icsk_ack.ato state. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11bpf: Enable BPF_PROG_TYPE_SK_REUSEPORT bpf prog in reuseport selectionMartin KaFai Lau
This patch allows a BPF_PROG_TYPE_SK_REUSEPORT bpf prog to select a SO_REUSEPORT sk from a BPF_MAP_TYPE_REUSEPORT_ARRAY introduced in the earlier patch. "bpf_run_sk_reuseport()" will return -ECONNREFUSED when the BPF_PROG_TYPE_SK_REUSEPORT prog returns SK_DROP. The callers, in inet[6]_hashtable.c and ipv[46]/udp.c, are modified to handle this case and return NULL immediately instead of continuing the sk search from its hashtable. It re-uses the existing SO_ATTACH_REUSEPORT_EBPF setsockopt to attach BPF_PROG_TYPE_SK_REUSEPORT. The "sk_reuseport_attach_bpf()" will check if the attaching bpf prog is in the new SK_REUSEPORT or the existing SOCKET_FILTER type and then check different things accordingly. One level of "__reuseport_attach_prog()" call is removed. The "sk_unhashed() && ..." and "sk->sk_reuseport_cb" tests are pushed back to "reuseport_attach_prog()" in sock_reuseport.c. sock_reuseport.c seems to have more knowledge on those test requirements than filter.c. In "reuseport_attach_prog()", after new_prog is attached to reuse->prog, the old_prog (if any) is also directly freed instead of returning the old_prog to the caller and asking the caller to free. The sysctl_optmem_max check is moved back to the "sk_reuseport_attach_filter()" and "sk_reuseport_attach_bpf()". As of other bpf prog types, the new BPF_PROG_TYPE_SK_REUSEPORT is only bounded by the usual "bpf_prog_charge_memlock()" during load time instead of bounded by both bpf_prog_charge_memlock and sysctl_optmem_max. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-11bpf: Introduce BPF_PROG_TYPE_SK_REUSEPORTMartin KaFai Lau
This patch adds a BPF_PROG_TYPE_SK_REUSEPORT which can select a SO_REUSEPORT sk from a BPF_MAP_TYPE_REUSEPORT_ARRAY. Like other non SK_FILTER/CGROUP_SKB program, it requires CAP_SYS_ADMIN. BPF_PROG_TYPE_SK_REUSEPORT introduces "struct sk_reuseport_kern" to store the bpf context instead of using the skb->cb[48]. At the SO_REUSEPORT sk lookup time, it is in the middle of transiting from a lower layer (ipv4/ipv6) to a upper layer (udp/tcp). At this point, it is not always clear where the bpf context can be appended in the skb->cb[48] to avoid saving-and-restoring cb[]. Even putting aside the difference between ipv4-vs-ipv6 and udp-vs-tcp. It is not clear if the lower layer is only ipv4 and ipv6 in the future and will it not touch the cb[] again before transiting to the upper layer. For example, in udp_gro_receive(), it uses the 48 byte NAPI_GRO_CB instead of IP[6]CB and it may still modify the cb[] after calling the udp[46]_lib_lookup_skb(). Because of the above reason, if sk->cb is used for the bpf ctx, saving-and-restoring is needed and likely the whole 48 bytes cb[] has to be saved and restored. Instead of saving, setting and restoring the cb[], this patch opts to create a new "struct sk_reuseport_kern" and setting the needed values in there. The new BPF_PROG_TYPE_SK_REUSEPORT and "struct sk_reuseport_(kern|md)" will serve all ipv4/ipv6 + udp/tcp combinations. There is no protocol specific usage at this point and it is also inline with the current sock_reuseport.c implementation (i.e. no protocol specific requirement). In "struct sk_reuseport_md", this patch exposes data/data_end/len with semantic similar to other existing usages. Together with "bpf_skb_load_bytes()" and "bpf_skb_load_bytes_relative()", the bpf prog can peek anywhere in the skb. The "bind_inany" tells the bpf prog that the reuseport group is bind-ed to a local INANY address which cannot be learned from skb. The new "bind_inany" is added to "struct sock_reuseport" which will be used when running the new "BPF_PROG_TYPE_SK_REUSEPORT" bpf prog in order to avoid repeating the "bind INANY" test on "sk_v6_rcv_saddr/sk->sk_rcv_saddr" every time a bpf prog is run. It can only be properly initialized when a "sk->sk_reuseport" enabled sk is adding to a hashtable (i.e. during "reuseport_alloc()" and "reuseport_add_sock()"). The new "sk_select_reuseport()" is the main helper that the bpf prog will use to select a SO_REUSEPORT sk. It is the only function that can use the new BPF_MAP_TYPE_REUSEPORT_ARRAY. As mentioned in the earlier patch, the validity of a selected sk is checked in run time in "sk_select_reuseport()". Doing the check in verification time is difficult and inflexible (consider the map-in-map use case). The runtime check is to compare the selected sk's reuseport_id with the reuseport_id that we want. This helper will return -EXXX if the selected sk cannot serve the incoming request (e.g. reuseport_id not match). The bpf prog can decide if it wants to do SK_DROP as its discretion. When the bpf prog returns SK_PASS, the kernel will check if a valid sk has been selected (i.e. "reuse_kern->selected_sk != NULL"). If it does , it will use the selected sk. If not, the kernel will select one from "reuse->socks[]" (as before this patch). The SK_DROP and SK_PASS handling logic will be in the next patch. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-06ipv4: frags: precedence bug in ip_expire()Dan Carpenter
We accidentally removed the parentheses here, but they are required because '!' has higher precedence than '&'. Fixes: fa0f527358bd ("ip: use rb trees for IP frag queue.") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-05ip: use rb trees for IP frag queue.Peter Oskolkov
Similar to TCP OOO RX queue, it makes sense to use rb trees to store IP fragments, so that OOO fragments are inserted faster. Tested: - a follow-up patch contains a rather comprehensive ip defrag self-test (functional) - ran neper `udp_stream -c -H <host> -F 100 -l 300 -T 20`: netstat --statistics Ip: 282078937 total packets received 0 forwarded 0 incoming packets discarded 946760 incoming packets delivered 18743456 requests sent out 101 fragments dropped after timeout 282077129 reassemblies required 944952 packets reassembled ok 262734239 packet reassembles failed (The numbers/stats above are somewhat better re: reassemblies vs a kernel without this patchset. More comprehensive performance testing TBD). Reported-by: Jann Horn <jannh@google.com> Reported-by: Juha-Matti Tilli <juha-matti.tilli@iki.fi> Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Peter Oskolkov <posk@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>