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2017-11-15tcp: Namespace-ify sysctl_tcp_default_congestion_controlStephen Hemminger5-51/+60
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>
2017-11-15net: Protect iterations over net::fib_notifier_ops in fib_seq_sum()Kirill Tkhai1-1/+3
There is at least unlocked deletion of net->ipv4.fib_notifier_ops from net::fib_notifier_ops: ip_fib_net_exit() rtnl_unlock() fib4_notifier_exit() fib_notifier_ops_unregister(net->ipv4.notifier_ops) list_del_rcu(&ops->list) So fib_seq_sum() can't use rtnl_lock() only for protection. The possible solution could be to use rtnl_lock() in fib_notifier_ops_unregister(), but this adds a possible delay during net namespace creation, so we better use rcu_read_lock() till someone really needs the mutex (if that happens). Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-15ipv6: set all.accept_dad to 0 by defaultNicolas Dichtel1-1/+1
With commits 35e015e1f577 and a2d3f3e33853, the global 'accept_dad' flag is also taken into account (default value is 1). If either global or per-interface flag is non-zero, DAD will be enabled on a given interface. This is not backward compatible: before those patches, the user could disable DAD just by setting the per-interface flag to 0. Now, the user instead needs to set both flags to 0 to actually disable DAD. Restore the previous behaviour by setting the default for the global 'accept_dad' flag to 0. This way, DAD is still enabled by default, as per-interface flags are set to 1 on device creation, but setting them to 0 is enough to disable DAD on a given interface. - Before 35e015e1f57a7 and a2d3f3e33853: global per-interface DAD enabled [default] 1 1 yes X 0 no X 1 yes - After 35e015e1f577 and a2d3f3e33853: global per-interface DAD enabled [default] 1 1 yes 0 0 no 0 1 yes 1 0 yes - After this fix: global per-interface DAD enabled 1 1 yes 0 0 no [default] 0 1 yes 1 0 yes Fixes: 35e015e1f577 ("ipv6: fix net.ipv6.conf.all interface DAD handlers") Fixes: a2d3f3e33853 ("ipv6: fix net.ipv6.conf.all.accept_dad behaviour for real") CC: Stefano Brivio <sbrivio@redhat.com> CC: Matteo Croce <mcroce@redhat.com> CC: Erik Kline <ek@google.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net-sysfs: trigger netlink notification on ifalias change via sysfsRoopa Prabhu1-3/+14
This patch adds netlink notifications on iflias changes via sysfs. makes it consistent with the netlink path which also calls netdev_state_change. Also makes it consistent with other sysfs netdev_store operations. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14openvswitch: Using kfree_rcu() to simplify the codeWei Yongjun1-8/+1
The callback function of call_rcu() just calls a kfree(), so we can use kfree_rcu() instead of call_rcu() + callback function. Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14openvswitch: Make local function ovs_nsh_key_attr_size() staticWei Yongjun1-1/+1
Fixes the following sparse warnings: net/openvswitch/flow_netlink.c:340:8: warning: symbol 'ovs_nsh_key_attr_size' was not declared. Should it be static? Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14openvswitch: Fix return value check in ovs_meter_cmd_features()Wei Yongjun1-1/+1
In case of error, the function ovs_meter_cmd_reply_start() returns ERR_PTR() not NULL. The NULL test in the return value check should be replaced with IS_ERR(). Fixes: 96fbc13d7e77 ("openvswitch: Add meter infrastructure") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net: bridge: add vlan_tunnel to bridge port policiesNikolay Aleksandrov1-0/+1
Found another missing port flag policy entry for IFLA_BRPORT_VLAN_TUNNEL so add it now. CC: Roopa Prabhu <roopa@cumulusnetworks.com> Fixes: efa5356b0d97 ("bridge: per vlan dst_metadata netlink support") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14netlink: remove unnecessary forward declarationJohannes Berg1-1/+0
netlink_skb_destructor() is actually defined before the first usage in the file, so remove the unnecessary forward declaration. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net: dsa: lan9303: calculate offload_fwd_mark from tagEgil Hjelmeland1-16/+8
The lan9303 set bits in the host CPU tag indicating if a ingress frame is a trapped IGMP or STP frame. Use these bits to calculate skb->offload_fwd_mark more efficiently. Signed-off-by: Egil Hjelmeland <privat@egil-hjelmeland.no> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net: core: dev_get_valid_name is now the same as dev_alloc_name_nsRasmus Villemoes1-13/+1
If name contains a %, it's easy to see that this patch doesn't change anything (other than eliminate the duplicate dev_valid_name call). Otherwise, we'll now just spend a little time in snprintf() copying name to the stack buffer allocated in dev_alloc_name_ns, and do the __dev_get_by_name using that buffer rather than name. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net: core: maybe return -EEXIST in __dev_alloc_nameRasmus Villemoes1-1/+1
If we're given format string with no %d, -EEXIST is a saner error code. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net: core: check dev_valid_name in __dev_alloc_nameRasmus Villemoes1-0/+3
We currently only exclude non-sysfs-friendly names via dev_get_valid_name; there doesn't seem to be a reason to allow such names when we're called via dev_alloc_name. This does duplicate the dev_valid_name check in the dev_get_valid_name() case; we'll fix that shortly. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net: core: drop pointless check in __dev_alloc_nameRasmus Villemoes1-2/+1
The only caller passes a stack buffer as buf, so it won't equal the passed-in name. Moreover, we're already using buf as a scratch buffer inside the if (p) {} block, so if buf and name were the same, that snprintf() call would be overwriting its own format string. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net: core: eliminate dev_alloc_name{,_ns} code duplicationRasmus Villemoes1-10/+2
dev_alloc_name contained a BUG_ON(), which I moved to dev_alloc_name_ns; the only other caller of that already has the same BUG_ON. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net: core: move dev_alloc_name_ns a little higherRasmus Villemoes1-13/+13
No functional change. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net: core: improve sanity checking in __dev_alloc_nameRasmus Villemoes1-1/+1
__dev_alloc_name is called from the public (and exported) dev_alloc_name(), so we don't have a guarantee that strlen(name) is at most IFNAMSIZ. If somebody manages to get __dev_alloc_name called with a % char beyond the 31st character, we'd be making a snprintf() call that will very easily crash the kernel (using an appropriate %p extension, we'll likely dereference some completely bogus pointer). In the normal case where strlen() is sane, we don't even save anything by limiting to IFNAMSIZ, so just use strchr(). Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14tls: don't override sk_write_space if tls_set_sw_offload fails.Ilya Lesokhin1-3/+2
If we fail to enable tls in the kernel we shouldn't override the sk_write_space callback Fixes: 3c4d7559159b ('tls: kernel TLS support') Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14tls: Avoid copying crypto_info again after cipher_type check.Ilya Lesokhin1-17/+12
Avoid copying crypto_info again after cipher_type check to avoid a TOCTOU exploits. The temporary array on the stack is removed as we don't really need it Fixes: 3c4d7559159b ('tls: kernel TLS support') Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14tls: Move tls_make_aad to header to allow sharingIlya Lesokhin1-17/+1
move tls_make_aad as it is going to be reused by the device offload code and rx path. Remove unused recv parameter. Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14tls: Fix TLS ulp context leak, when TLS_TX setsockopt is not used.Ilya Lesokhin2-10/+16
Previously the TLS ulp context would leak if we attached a TLS ulp to a socket but did not use the TLS_TX setsockopt, or did use it but it failed. This patch solves the issue by overriding prot[TLS_BASE_TX].close and fixing tls_sk_proto_close to work properly when its called with ctx->tx_conf == TLS_BASE_TX. This patch also removes ctx->free_resources as we can use ctx->tx_conf to obtain the relevant information. Fixes: 3c4d7559159b ('tls: kernel TLS support') Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14tls: Add function to update the TLS socket configurationIlya Lesokhin1-14/+32
The tx configuration is now stored in ctx->tx_conf. And sk->sk_prot is updated trough a function This will simplify things when we add rx and support for different possible tx and rx cross configurations. Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14tls: Use kzalloc for aead_request allocationIlya Lesokhin1-1/+1
Use kzalloc for aead_request allocation as we don't set all the bits in the request. Fixes: 3c4d7559159b ('tls: kernel TLS support') Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14tcp: allow drivers to tweak TSQ logicEric Dumazet2-2/+3
I had many reports that TSQ logic breaks wifi aggregation. Current logic is to allow up to 1 ms of bytes to be queued into qdisc and drivers queues. But Wifi aggregation needs a bigger budget to allow bigger rates to be discovered by various TCP Congestion Controls algorithms. This patch adds an extra socket field, allowing wifi drivers to select another log scale to derive TCP Small Queue credit from current pacing rate. Initial value is 10, meaning that this patch does not change current behavior. We expect wifi drivers to set this field to smaller values (tests have been done with values from 6 to 9) They would have to use following template : if (skb->sk && skb->sk->sk_pacing_shift != MY_PACING_SHIFT) skb->sk->sk_pacing_shift = MY_PACING_SHIFT; Ref: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1670041 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Johannes Berg <johannes.berg@intel.com> Cc: Toke Høiland-Jørgensen <toke@toke.dk> Cc: Kir Kolyshkin <kir@openvz.org> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14Merge tag 'rxrpc-next-20171111' of ↵David S. Miller7-7/+36
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs David Howells says: ==================== rxrpc: Fixes Here are some patches that fix some things in AF_RXRPC: (1) Prevent notifications from being passed to a kernel service for a call that it has ended. (2) Fix a null pointer deference that occurs under some circumstances when an ACK is generated. (3) Fix a number of things to do with call expiration. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14xfrm6_tunnel: exit_net cleanup check addedVasily Averin1-0/+8
Be sure that spi_byaddr and spi_byspi arrays initialized in net_init hook were return to initial state Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14phonet: exit_net cleanup check addedVasily Averin1-0/+3
Be sure that pndevs.list initialized in net_init hook was return to initial state. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14l2tp: exit_net cleanup check addedVasily Averin1-0/+4
Be sure that l2tp_session_hlist array initialized in net_init hook was return to initial state. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14fib_rules: exit_net cleanup check addedVasily Averin1-0/+6
Be sure that rules_ops list initialized in net_init hook was return to initial state. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14fib_notifier: exit_net cleanup check addedVasily Averin1-0/+6
Be sure that fib_notifier_ops list initilized in net_init hook was return to initial state. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14netdev: exit_net cleanup check addedVasily Averin1-0/+2
Be sure that dev_base_head list initialized in net_init hook was return to initial state Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14packet: exit_net cleanup check addedVasily Averin1-0/+1
Be sure that packet.sklist initialized in net_init hook was return to initial state. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14af_key: replace BUG_ON on WARN_ON in net_exit hookVasily Averin1-1/+1
Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14net: dsa: Fix dependencies on bridgeAndrew Lunn1-0/+1
DSA now uses one of the symbols exported by the bridge, br_vlan_enabled(). This has a stub, if the bridge is not enabled. However, if the bridge is enabled, we cannot have DSA built in and the bridge as a module, otherwise we get undefined symbols at link time: net/dsa/port.o: In function `dsa_port_vlan_add': net/dsa/port.c:255: undefined reference to `br_vlan_enabled' net/dsa/port.o: In function `dsa_port_vlan_del': net/dsa/port.c:270: undefined reference to `br_vlan_enabled' Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13ip6_tunnel: clean up ip4ip6 and ip6ip6's err_handlersXin Long1-28/+14
This patch is to remove some useless codes of redirect and fix some indents on ip4ip6 and ip6ip6's err_handlers. Note that redirect icmp packet is already processed in ip6_tnl_err, the old redirect codes in ip4ip6_err actually never worked even before this patch. Besides, there's no need to send redirect to user's sk, it's for lower dst, so just remove it in this patch. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13ip6_tunnel: process toobig in a better wayXin Long1-4/+3
The same improvement in "ip6_gre: process toobig in a better way" is needed by ip4ip6 and ip6ip6 as well. Note that ip4ip6 and ip6ip6 will also update sk dst pmtu in their err_handlers. Like I said before, gre6 could not do this as it's inner proto is not certain. But for all of them, sk dst pmtu will be updated in tx path if in need. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13ip6_tunnel: add the process for redirect in ip6_tnl_errXin Long1-5/+10
The same process for redirect in "ip6_gre: add the process for redirect in ip6gre_err" is needed by ip4ip6 and ip6ip6 as well. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13ip6_gre: process toobig in a better wayXin Long1-13/+2
Now ip6gre processes toobig icmp packet by setting gre dev's mtu in ip6gre_err, which would cause few things not good: - It couldn't set mtu with dev_set_mtu due to it's not in user context, which causes route cache and idev->cnf.mtu6 not to be updated. - It has to update sk dst pmtu in tx path according to gredev->mtu for ip6gre, while it updates pmtu again according to lower dst pmtu in ip6_tnl_xmit. - To change dev->mtu by toobig icmp packet is not a good idea, it should only work on pmtu. This patch is to process toobig by updating the lower dst's pmtu, as later sk dst pmtu will be updated in ip6_tnl_xmit, the same way as in ip4gre. Note that gre dev's mtu will not be updated any more, it doesn't make any sense to change dev's mtu after receiving a toobig packet. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13ip6_gre: add the process for redirect in ip6gre_errXin Long1-0/+5
This patch is to add redirect icmp packet process for ip6gre by calling ip6_redirect() in ip6gre_err(), as in vti6_err. Prior to this patch, there's even no route cache generated after receiving redirect. 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>
2017-11-13Merge tag 'nfc-next-4.15-1' of ↵David S. Miller6-32/+52
git://git.kernel.org/pub/scm/linux/kernel/git/sameo/nfc-next Samuel Ortiz says: ==================== NFC 4.15 pull request This is the NFC pull request for 4.15. We have: - A new netlink command for explicitly deactivating NFC targets - i2c constification for all NFC drivers - One NFC device allocation error path fix ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13openvswitch: Add meter action supportAndy Zhou3-0/+13
Implements OVS kernel meter action support. Signed-off-by: Andy Zhou <azhou@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13openvswitch: Add meter infrastructureAndy Zhou5-2/+674
OVS kernel datapath so far does not support Openflow meter action. This is the first stab at adding kernel datapath meter support. This implementation supports only drop band type. Signed-off-by: Andy Zhou <azhou@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13openvswitch: export get_dp() API.Andy Zhou2-29/+31
Later patches will invoke get_dp() outside of datapath.c. Export it. Signed-off-by: Andy Zhou <azhou@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13net: dsa: Support prepended Broadcom tagFlorian Fainelli5-7/+40
Add a new type: DSA_TAG_PROTO_PREPEND which allows us to support for the 4-bytes Broadcom tag that we already support, but in a format where it is pre-pended to the packet instead of located between the MAC SA and the Ethertyper (DSA_TAG_PROTO_BRCM). Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13net: dsa: tag_brcm: Prepare for supporting prepended tagFlorian Fainelli1-11/+34
In preparation for supporting the same Broadcom tag format, but instead of inserted between the MAC SA and EtherType, prepended to the Ethernet frame, restructure the code a little bit to make that possible and take an offset parameter. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13net: dsa: Pass a port to get_tag_protocol()Florian Fainelli2-2/+2
A number of drivers want to check whether the configured CPU port is a possible configuration for enabling tagging, pass down the CPU port number so they verify that. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13net/sched/sch_red.c: work around gcc-4.4.4 anon union initializer issueAndrew Morton1-5/+9
gcc-4.4.4 (at lest) has issues with initializers and anonymous unions: net/sched/sch_red.c: In function 'red_dump_offload': net/sched/sch_red.c:282: error: unknown field 'stats' specified in initializer net/sched/sch_red.c:282: warning: initialization makes integer from pointer without a cast net/sched/sch_red.c:283: error: unknown field 'stats' specified in initializer net/sched/sch_red.c:283: warning: initialization makes integer from pointer without a cast net/sched/sch_red.c: In function 'red_dump_stats': net/sched/sch_red.c:352: error: unknown field 'xstats' specified in initializer net/sched/sch_red.c:352: warning: initialization makes integer from pointer without a cast Work around this. Fixes: 602f3baf2218 ("net_sch: red: Add offload ability to RED qdisc") Cc: Nogah Frankel <nogahf@mellanox.com> Cc: Jiri Pirko <jiri@mellanox.com> Cc: Simon Horman <simon.horman@netronome.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13af_netlink: ensure that NLMSG_DONE never fails in dumpsJason A. Donenfeld2-6/+12
The way people generally use netlink_dump is that they fill in the skb as much as possible, breaking when nla_put returns an error. Then, they get called again and start filling out the next skb, and again, and so forth. The mechanism at work here is the ability for the iterative dumping function to detect when the skb is filled up and not fill it past the brim, waiting for a fresh skb for the rest of the data. However, if the attributes are small and nicely packed, it is possible that a dump callback function successfully fills in attributes until the skb is of size 4080 (libmnl's default page-sized receive buffer size). The dump function completes, satisfied, and then, if it happens to be that this is actually the last skb, and no further ones are to be sent, then netlink_dump will add on the NLMSG_DONE part: nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI); It is very important that netlink_dump does this, of course. However, in this example, that call to nlmsg_put_answer will fail, because the previous filling by the dump function did not leave it enough room. And how could it possibly have done so? All of the nla_put variety of functions simply check to see if the skb has enough tailroom, independent of the context it is in. In order to keep the important assumptions of all netlink dump users, it is therefore important to give them an skb that has this end part of the tail already reserved, so that the call to nlmsg_put_answer does not fail. Otherwise, library authors are forced to find some bizarre sized receive buffer that has a large modulo relative to the common sizes of messages received, which is ugly and buggy. This patch thus saves the NLMSG_DONE for an additional message, for the case that things are dangerously close to the brim. This requires keeping track of the errno from ->dump() across calls. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13netem: support delivering packets in delayed time slotsDave Taht1-3/+71
Slotting is a crude approximation of the behaviors of shared media such as cable, wifi, and LTE, which gather up a bunch of packets within a varying delay window and deliver them, relative to that, nearly all at once. It works within the existing loss, duplication, jitter and delay parameters of netem. Some amount of inherent latency must be specified, regardless. The new "slot" parameter specifies a minimum and maximum delay between transmission attempts. The "bytes" and "packets" parameters can be used to limit the amount of information transferred per slot. Examples of use: tc qdisc add dev eth0 root netem delay 200us \ slot 800us 10ms bytes 64k packets 42 A more correct example, using stacked netem instances and a packet limit to emulate a tail drop wifi queue with slots and variable packet delivery, with a 200Mbit isochronous underlying rate, and 20ms path delay: tc qdisc add dev eth0 root handle 1: netem delay 20ms rate 200mbit \ limit 10000 tc qdisc add dev eth0 parent 1:1 handle 10:1 netem delay 200us \ slot 800us 10ms bytes 64k packets 42 limit 512 Signed-off-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13netem: add uapi to express delay and jitter in nanosecondsDave Taht1-0/+14
netem userspace has long relied on a horrible /proc/net/psched hack to translate the current notion of "ticks" to nanoseconds. Expressing latency and jitter instead, in well defined nanoseconds, increases the dynamic range of emulated delays and jitter in netem. It will also ease a transition where reducing a tick to nsec equivalence would constrain the max delay in prior versions of netem to only 4.3 seconds. Signed-off-by: Dave Taht <dave.taht@gmail.com> Suggested-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>