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* Merge branch 'master' of ↵Pablo Neira Ayuso2015-10-17178-1983/+5237
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next This merge resolves conflicts with 75aec9df3a78 ("bridge: Remove br_nf_push_frag_xmit_sk") as part of Eric Biederman's effort to improve netns support in the network stack that reached upstream via David's net-next tree. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Conflicts: net/bridge/br_netfilter_hooks.c
| * net: introduce pre-change upper device notifierJiri Pirko2015-10-161-0/+9
| | | | | | | | | | | | | | | | | | | | | | This newly introduced netdevice notifier is called before actual change upper happens. That provides a possibility for notifier handlers to know upper change will happen and react to it, including possibility to forbid the change. That is valuable for drivers which can check if the upper device linkage is supported and forbid that in case it is not. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: Fix suspicious RCU usage in fib_rebalanceDavid Ahern2015-10-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This command: ip route add 192.168.1.0/24 nexthop via 10.2.1.5 dev eth1 nexthop via 10.2.2.5 dev eth2 generated this suspicious RCU usage message: [ 63.249262] [ 63.249939] =============================== [ 63.251571] [ INFO: suspicious RCU usage. ] [ 63.253250] 4.3.0-rc3+ #298 Not tainted [ 63.254724] ------------------------------- [ 63.256401] ../include/linux/inetdevice.h:205 suspicious rcu_dereference_check() usage! [ 63.259450] [ 63.259450] other info that might help us debug this: [ 63.259450] [ 63.262297] [ 63.262297] rcu_scheduler_active = 1, debug_locks = 1 [ 63.264647] 1 lock held by ip/2870: [ 63.265896] #0: (rtnl_mutex){+.+.+.}, at: [<ffffffff813ebfb7>] rtnl_lock+0x12/0x14 [ 63.268858] [ 63.268858] stack backtrace: [ 63.270409] CPU: 4 PID: 2870 Comm: ip Not tainted 4.3.0-rc3+ #298 [ 63.272478] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 63.275745] 0000000000000001 ffff8800b8c9f8b8 ffffffff8125f73c ffff88013afcf301 [ 63.278185] ffff8800bab7a380 ffff8800b8c9f8e8 ffffffff8107bf30 ffff8800bb728000 [ 63.280634] ffff880139fe9a60 0000000000000000 ffff880139fe9a00 ffff8800b8c9f908 [ 63.283177] Call Trace: [ 63.283959] [<ffffffff8125f73c>] dump_stack+0x4c/0x68 [ 63.285593] [<ffffffff8107bf30>] lockdep_rcu_suspicious+0xfa/0x103 [ 63.287500] [<ffffffff8144d752>] __in_dev_get_rcu+0x48/0x4f [ 63.289169] [<ffffffff8144d797>] fib_rebalance+0x3e/0x127 [ 63.290753] [<ffffffff8144d986>] ? rcu_read_unlock+0x3e/0x5f [ 63.292442] [<ffffffff8144ea45>] fib_create_info+0xaf9/0xdcc [ 63.294093] [<ffffffff8106c12f>] ? sched_clock_local+0x12/0x75 [ 63.295791] [<ffffffff8145236a>] fib_table_insert+0x8c/0x451 [ 63.297493] [<ffffffff8144bf9c>] ? fib_get_table+0x36/0x43 [ 63.299109] [<ffffffff8144c3ca>] inet_rtm_newroute+0x43/0x51 [ 63.300709] [<ffffffff813ef684>] rtnetlink_rcv_msg+0x182/0x195 [ 63.302334] [<ffffffff8107d04c>] ? trace_hardirqs_on+0xd/0xf [ 63.303888] [<ffffffff813ebfb7>] ? rtnl_lock+0x12/0x14 [ 63.305346] [<ffffffff813ef502>] ? __rtnl_unlock+0x12/0x12 [ 63.306878] [<ffffffff81407c4c>] netlink_rcv_skb+0x3d/0x90 [ 63.308437] [<ffffffff813ec00e>] rtnetlink_rcv+0x21/0x28 [ 63.309916] [<ffffffff81407742>] netlink_unicast+0xfa/0x17f [ 63.311447] [<ffffffff81407a5e>] netlink_sendmsg+0x297/0x2dc [ 63.313029] [<ffffffff813c6cd4>] sock_sendmsg_nosec+0x12/0x1d [ 63.314597] [<ffffffff813c835b>] ___sys_sendmsg+0x196/0x21b [ 63.316125] [<ffffffff8100bf9f>] ? native_sched_clock+0x1f/0x3c [ 63.317671] [<ffffffff8106c12f>] ? sched_clock_local+0x12/0x75 [ 63.319185] [<ffffffff8106c397>] ? sched_clock_cpu+0x9d/0xb6 [ 63.320693] [<ffffffff8107e2d7>] ? __lock_is_held+0x32/0x54 [ 63.322145] [<ffffffff81159fcb>] ? __fget_light+0x4b/0x77 [ 63.323541] [<ffffffff813c8726>] __sys_sendmsg+0x3d/0x5b [ 63.324947] [<ffffffff813c8751>] SyS_sendmsg+0xd/0x19 [ 63.326274] [<ffffffff814c8f57>] entry_SYSCALL_64_fastpath+0x12/0x6f It looks like all of the code paths to fib_rebalance are under rtnl. Fixes: 0e884c78ee19 ("ipv4: L3 hash-based multipath") Cc: Peter Nørlund <pch@ordbogen.com> Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tcp/dccp: fix race at listener dismantle phaseEric Dumazet2015-10-161-22/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Under stress, a close() on a listener can trigger the WARN_ON(sk->sk_ack_backlog) in inet_csk_listen_stop() We need to test if listener is still active before queueing a child in inet_csk_reqsk_queue_add() Create a common inet_child_forget() helper, and use it from inet_csk_reqsk_queue_add() and inet_csk_listen_stop() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tcp/dccp: add inet_csk_reqsk_queue_drop_and_put() helperEric Dumazet2015-10-165-6/+12
| | | | | | | | | | | | | | | | | | | | Let's reduce the confusion about inet_csk_reqsk_queue_drop() : In many cases we also need to release reference on request socket, so add a helper to do this, reducing code size and complexity. Fixes: 4bdc3d66147b ("tcp/dccp: fix behavior of stale SYN_RECV request sockets") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * Revert "inet: fix double request socket freeing"Eric Dumazet2015-10-162-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit c69736696cf3742b37d850289dc0d7ead177bb14. At the time of above commit, tcp_req_err() and dccp_req_err() were dead code, as SYN_RECV request sockets were not yet in ehash table. Real bug was fixed later in a different commit. We need to revert to not leak a refcount on request socket. inet_csk_reqsk_queue_drop_and_put() will be added in following commit to make clean inet_csk_reqsk_queue_drop() does not release the reference owned by caller. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tipc: update node FSM when peer RESET message is receivedJon Paul Maloy2015-10-163-6/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The change made in the previous commit revealed a small flaw in the way the node FSM is updated. When the function tipc_node_link_down() is called for the last link to a node, we should check whether this was caused by a local reset or by a received RESET message from the peer. In the latter case, we can directly issue a PEER_LOST_CONTACT_EVT to the node FSM, so that it is ready to re-establish contact. If this is not done, the peer node will sometimes have to go through a second establish cycle before the link becomes stable. We fix this in this commit by conditionally issuing the mentioned event in the function tipc_node_link_down(). We also move LINK_RESET FSM even away from the link_reset() function and into the caller function, partially because it is easier to follow the code when state changes are gathered at a limited number of locations, partially because there will be cases in future commits where we don't want the link to go RESET mode when link_reset() is called. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tipc: send out RESET immediately when link goes downJon Paul Maloy2015-10-165-8/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a link is taken down because of a node local event, such as disabling of a bearer or an interface, we currently leave it to the peer node to discover the broken communication. The default time for such failure discovery is 1.5-2 seconds. If we instead allow the terminating link endpoint to send out a RESET message at the moment it is reset, we can achieve the impression that both endpoints are going down instantly. Since this is a very common scenario, we find it worthwhile to make this small modification. Apart from letting the link produce the said message, we also have to ensure that the interface is able to transmit it before TIPC is detached. We do this by performing the disabling of a bearer in three steps: 1) Disable reception of TIPC packets from the interface in question. 2) Take down the links, while allowing them so send out a RESET message. 3) Disable transmission of TIPC packets on the interface. Apart from this, we now have to react on the NETDEV_GOING_DOWN event, instead of as currently the NEDEV_DOWN event, to ensure that such transmission is possible during the teardown phase. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tipc: delay ESTABLISH state event when link is establishedJon Paul Maloy2015-10-163-23/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Link establishing, just like link teardown, is a non-atomic action, in the sense that discovering that conditions are right to establish a link, and the actual adding of the link to one of the node's send slots is done in two different lock contexts. The link FSM is designed to help bridging the gap between the two contexts in a safe manner. We have now discovered a weakness in the implementaton of this FSM. Because we directly let the link go from state LINK_ESTABLISHING to state LINK_ESTABLISHED already in the first lock context, we are unable to distinguish between a fully established link, i.e., a link that has been added to its slot, and a link that has not yet reached the second lock context. It may hence happen that a manual intervention, e.g., when disabling an interface, causes the function tipc_node_link_down() to try removing the link from the node slots, decrementing its active link counter etc, although the link was never added there in the first place. We solve this by delaying the actual state change until we reach the second lock context, inside the function tipc_node_link_up(). This makes it possible for potentail callers of __tipc_node_link_down() to know if they should proceed or not, and the problem is solved. Unforunately, the situation described above also has a second problem. Since there by necessity is a tipc_node_link_up() call pending once the node lock has been released, we must defuse that call by setting the link back from LINK_ESTABLISHING to LINK_RESET state. This forces us to make a slight modification to the link FSM, which will now look as follows. +------------------------------------+ |RESET_EVT | | | | +--------------+ | +-----------------| SYNCHING |-----------------+ | |FAILURE_EVT +--------------+ PEER_RESET_EVT| | | A | | | | | | | | | | | | | | |SYNCH_ |SYNCH_ | | | |BEGIN_EVT |END_EVT | | | | | | | V | V V | +-------------+ +--------------+ +------------+ | | RESETTING |<---------| ESTABLISHED |--------->| PEER_RESET | | +-------------+ FAILURE_ +--------------+ PEER_ +------------+ | | EVT | A RESET_EVT | | | | | | | | +----------------+ | | | RESET_EVT| |RESET_EVT | | | | | | | | | | |ESTABLISH_EVT | | | | +-------------+ | | | | | | RESET_EVT | | | | | | | | | | | V V V | | | | +-------------+ +--------------+ RESET_EVT| +--->| RESET |--------->| ESTABLISHING |<----------------+ +-------------+ PEER_ +--------------+ | A RESET_EVT | | | | | | | |FAILOVER_ |FAILOVER_ |FAILOVER_ |BEGIN_EVT |END_EVT |BEGIN_EVT | | | V | | +-------------+ | | FAILINGOVER |<----------------+ +-------------+ Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tipc: disallow packet duplicates in link deferred queueJon Paul Maloy2015-10-163-33/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After the previous commits, we are guaranteed that no packets of type LINK_PROTOCOL or with illegal sequence numbers will be attempted added to the link deferred queue. This makes it possible to make some simplifications to the sorting algorithm in the function tipc_skb_queue_sorted(). We also alter the function so that it will drop packets if one with the same seqeunce number is already present in the queue. This is necessary because we have identified weird packet sequences, involving duplicate packets, where a legitimate in-sequence packet may advance to the head of the queue without being detected and de-queued. Finally, we make this function outline, since it will now be called only in exceptional cases. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tipc: improve sequence number checkingJon Paul Maloy2015-10-162-15/+13Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sequence number of an incoming packet is currently only checked for less than, equality to, or bigger than the next expected number, meaning that the receive window in practice becomes one half sequence number cycle, or U16_MAX/2. This does not make sense, and may not even be safe if there are extreme delays in the network. Any packet sent by the peer during the ongoing cycle must belong inside his current send window, or should otherwise be dropped if possible. Since a link endpoint cannot know its peer's current send window, it has to base this sanity check on a worst-case assumption, i.e., that the peer is using a maximum sized window of 8191 packets. Using this assumption, we now add a check that the sequence number is not bigger than next_expected + TIPC_MAX_LINK_WIN. We also re-order the checks done, so that the receive window test is performed before the gap test. This way, we are guaranteed that no packet with illegal sequence numbers are ever added to the deferred queue. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tipc: simplify tipc_link_rcv() reception loopJon Paul Maloy2015-10-161-37/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, all packets received in tipc_link_rcv() are unconditionally added to the packet deferred queue, whereafter that queue is walked and all its buffers evaluated for delivery. This is both non-optimal and and makes the queue sorting function unnecessary complex. This commit changes the loop so that an arrived packet is evaluated first, and added to the deferred queue only when a sequence number gap is discovered. A non-empty deferred queue is walked until it is empty or until its head's sequence number doesn't fit. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tipc: limit usage of temporary skb list during packet receptionJon Paul Maloy2015-10-161-8/+7Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During packet reception, the function tipc_link_rcv() adds its accepted packets to a temporary buffer queue, before finally splicing this queue into the lock protected input queue that will be delivered up to the socket layer. The purpose is to reduce potential contention on the input queue lock. However, since the vast majority of packets arrive in sequence, they will anyway be added one by one to the input queue, and the use of the temporary queue becomes a sub-optimization. The only case where this queue makes sense is when unpacking buffers from a bundle packet; here we want to avoid dozens of small buffers to be added individually to the lock-protected input queue in a tight loop. In this commit, we remove the general usage of the temporary queue, and keep it only for the packet unbundling case. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * switchdev: assert rtnl mutex when going over lower netdevsJiri Pirko2015-10-151-4/+11
| | | | | | | | | | | | | | | | netdev_for_each_lower_dev has to be called with rtnl mutex held. So better enforce it in switchdev functions. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * bridge: defer switchdev fdb del call in fdb_del_external_learnJiri Pirko2015-10-152-1/+7
| | | | | | | | | | | | | | | | | | Since spinlock is held here, defer the switchdev operation. Also, ensure that defered switchdev ops are processed before port master device is unlinked. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * switchdev: introduce possibility to defer obj_add/delJiri Pirko2015-10-151-20/+80
| | | | | | | | | | | | | | | | | | | | | | | | Similar to the attr usecase, the caller knows if he is holding RTNL and is in atomic section. So let the called to decide the correct call variant. This allows drivers to sleep inside their ops and wait for hw to get the operation status. Then the status is propagated into switchdev core. This avoids silent errors in drivers. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * switchdev: remove pointers from switchdev objectsJiri Pirko2015-10-153-6/+9
| | | | | | | | | | | | | | | | | | | | | | When object is used in deferred work, we cannot use pointers in switchdev object structures because the memory they point at may be already used by someone else. So rather do local copy of the value. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Scott Feldman <sfeldma@gmail.com> Reviewed-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * switchdev: allow caller to explicitly request attr_set as deferredJiri Pirko2015-10-152-66/+45Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Caller should know if he can call attr_set directly (when holding RTNL) or if he has to defer the att_set processing for later. This also allows drivers to sleep inside attr_set and report operation status back to switchdev core. Switchdev core then warns if status is not ok, instead of silent errors happening in drivers. Benefit from newly introduced switchdev deferred ops infrastructure. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * switchdev: make struct switchdev_attr parameter const for attr_set callsJiri Pirko2015-10-152-4/+5
| | | | | | | | | | | | Signed-off-by: Jiri Pirko <jiri@mellanox.com> Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * switchdev: introduce switchdev deferred ops infrastructureJiri Pirko2015-10-151-0/+80
| | | | | | | | | | | | | | | | | | Introduce infrastructure which will be used internally to defer ops. Note that the deferred ops are queued up and either are processed by scheduled work or explicitly by user calling deferred_process function. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tcp: avoid spurious SYN flood detection at listen() timeEric Dumazet2015-10-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | At listen() time, there is a small window where listener is visible with a zero backlog, triggering a spurious "Possible SYN flooding on port" message. Nothing prevents us from setting the correct backlog. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tcp/dccp: fix potential NULL deref in __inet_inherit_port()Eric Dumazet2015-10-151-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | As we no longer hold listener lock in fast path, it is possible that a child is created right after listener freed its bound port, if a close() is done while incoming packets are processed. __inet_inherit_port() must detect this and return an error, so that caller can free the child earlier. Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets") Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * Merge tag 'linux-can-next-for-4.4-20151013' of ↵David S. Miller2015-10-151-5/+10
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next Marc Kleine-Budde says: ==================== pull-request: can-next 2015-09-17 this is a pull request of 4 patches for net-next/master. Two patches are by Gerhard Bertelsmann, fixing some problems in the sun4i driver. The patch by Arnd Bergmann stops using timeval for the CAN broadcast manager. The last patch by Alexandre Belloni removes the otherwise unused struct at91_can_data from the driver. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| | * can: avoid using timeval for uapiArnd Bergmann2015-10-131-5/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The can subsystem communicates with user space using a bcm_msg_head header, which contains two timestamps. This is problematic for multiple reasons: a) The structure layout is currently incompatible between 64-bit user space and 32-bit user space, and cannot work in compat mode (other than x32). b) The timeval structure layout will change in 32-bit user space when we fix the y2038 overflow problem by redefining time_t to 64-bit, making new 32-bit user space incompatible with the current kernel interface. Cars last a long time and often use old kernels, so the actual users of this code are the most likely ones to migrate to y2038 safe user space. This tries to work around part of the problem by changing the publicly visible user interface in the header, but not the binary interface. Fortunately, the values passed around in the structure are relative times and do not actually suffer from the y2038 overflow, so 32-bit is enough here. We replace the use of 'struct timeval' with a newly defined 'struct bcm_timeval' that uses the exact same binary layout as before and that still suffers from problem a) but not problem b). The downside of this approach is that any user space program that currently assigns a timeval structure to these members rather than writing the tv_sec/tv_usec portions individually will suffer a compile-time error when built with an updated kernel header. Fixing this error makes it work fine with old and new headers though. We could address problem a) by using '__u32' or 'int' members rather than 'long', but that would have a more significant downside in also breaking support for all existing 64-bit user binaries that might be using this interface, which is likely not acceptable. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Cc: linux-can@vger.kernel.org Cc: linux-api@vger.kernel.org Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| * | Revert "ipv4/icmp: redirect messages can use the ingress daddr as source"Paolo Abeni2015-10-142-15/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Revert the commit e2ca690b657f ("ipv4/icmp: redirect messages can use the ingress daddr as source"), which tried to introduce a more suitable behaviour for ICMP redirect messages generated by VRRP routers. However RFC 5798 section 8.1.1 states: The IPv4 source address of an ICMP redirect should be the address that the end-host used when making its next-hop routing decision. while said commit used the generating packet destination address, which do not match the above and in most cases leads to no redirect packets to be generated. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | tcp/dccp: fix behavior of stale SYN_RECV request socketsEric Dumazet2015-10-144-18/+26
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a TCP/DCCP listener is closed, its pending SYN_RECV request sockets become stale, meaning 3WHS can not complete. But current behavior is wrong : incoming packets finding such stale sockets are dropped. We need instead to cleanup the request socket and perform another lookup : - Incoming ACK will give a RST answer, - SYN rtx might find another listener if available. - We expedite cleanup of request sockets and old listener socket. Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * bridge: vlan: move back vlan_flushNikolay Aleksandrov2015-10-133-10/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Ido Schimmel reported a problem with switchdev devices because of the order change of del_nbp operations, more specifically the move of nbp_vlan_flush() which deletes all vlans and frees vlgrp after the rx_handler has been unregistered. So in order to fix this move vlan_flush back where it was and make it destroy the rhtable after NULLing vlgrp and waiting a grace period to make sure noone can see it. Reported-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * bridge: vlan: drop unnecessary flush codeNikolay Aleksandrov2015-10-131-8/+1Star
| | | | | | | | | | | | | | | | | | | | As Ido Schimmel pointed out the vlan_vid_del() code in nbp_vlan_flush is unnecessary (and is actually a remnant of the old vlan code) so we can remove it. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * bridge: vlan: use rcu for vlan_list traversal in br_fill_ifinfoNikolay Aleksandrov2015-10-131-8/+13
| | | | | | | | | | | | | | | | | | | | | | br_fill_ifinfo is called by br_ifinfo_notify which can be called from many contexts with different locks held, sometimes it relies upon bridge's spinlock only which is a problem for the vlan code, so use explicitly rcu for that to avoid problems. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * bridge: vlan: use proper rcu for the vlgrp memberNikolay Aleksandrov2015-10-136-53/+104
| | | | | | | | | | | | | | | | | | | | | | | | | | The bridge and port's vlgrp member is already used in RCU way, currently we rely on the fact that it cannot disappear while the port exists but that is error-prone and we might miss places with improper locking (either RCU or RTNL must be held to walk the vlan_list). So make it official and use RCU for vlgrp to catch offenders. Introduce proper vlgrp accessors and use them consistently throughout the code. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: Add VRF support to IPv6 stackDavid Ahern2015-10-135-14/+63
| | | | | | | | | | | | | | | | | | | | As with IPv4 support for VRFs added to IPv6 stack by replacing hardcoded table ids with possibly device specific ones and manipulating the oif in the flowi6. The flow flags are used to skip oif compare in nexthop lookups if the device is enslaved to a VRF via the L3 master device. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: Export fib6_get_table and nd_tblDavid Ahern2015-10-132-0/+2
| | | | | | | | | | Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * bridge: fix gc_timer mod/del race conditionNikolay Aleksandrov2015-10-131-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit c62987bbd8a1 ("bridge: push bridge setting ageing_time down to switchdev") introduced a timer race condition because the gc_timer can get rearmed after it's supposedly stopped and flushed in br_dev_delete() leading to a use of freed memory. So take rtnl to sync with bridge destruction when setting ageing_timer. Here's the trace reproduced with these two commands running in parallel: while :; do echo 10000 > /sys/class/net/br0/bridge/ageing_timer; done; while :; do brctl addbr br0; ip l set br0 up; ip l set br0 down; brctl delbr br0; done; [ 300.000029] BUG: unable to handle kernel paging request at ffffffff811c59d3 [ 300.000263] IP: [<ffffffff810f168e>] __internal_add_timer+0x2e/0xd0 [ 300.000422] PGD 1a0f067 PUD 1a10063 PMD 10001e1 [ 300.000639] Oops: 0003 [#1] SMP [ 300.000793] Modules linked in: bridge stp llc nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel ppdev aesni_intel aes_x86_64 glue_helper lrw gf128mul ablk_helper cryptd snd_hda_codec_generic qxl drm_kms_helper psmouse pcspkr ttm snd_hda_intel 9pnet_virtio evdev serio_raw joydev snd_hda_codec 9pnet virtio_balloon drm snd_hwdep virtio_console snd_hda_core pvpanic snd_pcm i2c_piix4 snd_timer acpi_cpufreq parport_pc snd parport soundcore button processor i2c_core ipv6 autofs4 hid_generic usbhid hid ext4 crc16 mbcache jbd2 sg sr_mod cdrom ata_generic virtio_blk virtio_net e1000 ehci_pci uhci_hcd ehci_hcd usbcore usb_common floppy ata_piix libata virtio_pci virtio_ring virtio scsi_mod [ 300.004008] CPU: 1 PID: 1169 Comm: bash Not tainted 4.3.0-rc3+ #46 [ 300.004008] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 300.004008] task: ffff880035be2200 ti: ffff88003795c000 task.ti: ffff88003795c000 [ 300.004008] RIP: 0010:[<ffffffff810f168e>] [<ffffffff810f168e>] __internal_add_timer+0x2e/0xd0 [ 300.004008] RSP: 0018:ffff88003fd03e78 EFLAGS: 00010046 [ 300.004008] RAX: ffff88003fd0ef60 RBX: 840fc78949c08548 RCX: 00000001ffffffff [ 300.004008] RDX: 0000000000000000 RSI: ffffffff811c59d3 RDI: ffff88003fd0df00 [ 300.004008] RBP: ffff88003fd03e78 R08: 00000000ffffffff R09: 0000000000000000 [ 300.004008] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88003fd0df00 [ 300.004008] R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff816032e0 [ 300.004008] FS: 00007fcbdd609700(0000) GS:ffff88003fd00000(0000) knlGS:0000000000000000 [ 300.004008] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 300.004008] CR2: ffffffff811c59d3 CR3: 0000000037879000 CR4: 00000000000406e0 [ 300.004008] Stack: [ 300.004008] ffff88003fd03ea8 ffffffff810f1775 ffff88003c8cb958 ffff88003fd0df00 [ 300.004008] 0000000000000000 0000000000000001 ffff88003fd03f18 ffffffff810f28c4 [ 300.004008] ffff88003fd0eb68 ffff88003fd0e968 ffff88003fd0e768 ffff88003fd0df68 [ 300.004008] Call Trace: [ 300.004008] <IRQ> [ 300.004008] [<ffffffff810f1775>] cascade+0x45/0x70 [ 300.004008] [<ffffffff810f28c4>] run_timer_softirq+0x2f4/0x340 [ 300.004008] [<ffffffff8107e380>] __do_softirq+0xd0/0x440 [ 300.004008] [<ffffffff8107e8a3>] irq_exit+0xb3/0xc0 [ 300.004008] [<ffffffff815c2032>] smp_apic_timer_interrupt+0x42/0x50 [ 300.004008] [<ffffffff815bfe37>] apic_timer_interrupt+0x87/0x90 [ 300.004008] <EOI> [ 300.004008] [<ffffffff811fb80c>] ? create_object+0x13c/0x2e0 [ 300.004008] [<ffffffff8109b23e>] ? __kernel_text_address+0x4e/0x70 [ 300.004008] [<ffffffff8109b23e>] ? __kernel_text_address+0x4e/0x70 [ 300.004008] [<ffffffff8101e17f>] print_context_stack+0x7f/0xf0 [ 300.004008] [<ffffffff8101d55b>] dump_trace+0x11b/0x300 [ 300.004008] [<ffffffff8102970b>] save_stack_trace+0x2b/0x50 [ 300.004008] [<ffffffff811fb80c>] create_object+0x13c/0x2e0 [ 300.004008] [<ffffffff815b2e8e>] kmemleak_alloc+0x4e/0xb0 [ 300.004008] [<ffffffff811e475d>] kmem_cache_alloc_trace+0x18d/0x2f0 [ 300.004008] [<ffffffff8128b139>] kernfs_fop_open+0xc9/0x380 [ 300.004008] [<ffffffff8120214f>] do_dentry_open+0x1ff/0x2f0 [ 300.004008] [<ffffffff8128b070>] ? kernfs_fop_release+0x70/0x70 [ 300.004008] [<ffffffff812034f9>] vfs_open+0x59/0x60 [ 300.004008] [<ffffffff812130de>] path_openat+0x1ce/0x1260 [ 300.004008] [<ffffffff812154ae>] do_filp_open+0x7e/0xe0 [ 300.004008] [<ffffffff812251ff>] ? __alloc_fd+0xaf/0x180 [ 300.004008] [<ffffffff8120387b>] do_sys_open+0x12b/0x210 [ 300.004008] [<ffffffff8120397e>] SyS_open+0x1e/0x20 [ 300.004008] [<ffffffff815bf0b6>] entry_SYSCALL_64_fastpath+0x16/0x7a [ 300.004008] Code: 66 90 48 8b 46 10 48 8b 4f 40 55 48 89 c2 48 89 e5 48 29 ca 48 81 fa ff 00 00 00 77 20 0f b6 c0 48 8d 44 c7 68 48 8b 10 48 85 d2 <48> 89 16 74 04 48 89 72 08 48 89 30 48 89 46 08 5d c3 48 81 fa [ 300.004008] RIP [<ffffffff810f168e>] __internal_add_timer+0x2e/0xd0 [ 300.004008] RSP <ffff88003fd03e78> [ 300.004008] CR2: ffffffff811c59d3 Fixes: c62987bbd8a1 ("bridge: push bridge setting ageing_time down to switchdev") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * switchdev: enforce no pvid flag in vlan rangesNikolay Aleksandrov2015-10-131-0/+3
| | | | | | | | | | | | | | | | | | We shouldn't allow BRIDGE_VLAN_INFO_PVID flag in VLAN ranges. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Acked-by: Elad Raz <eladr@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: dsa: do not warn unsupported bridge opsVivien Didelot2015-10-131-1/+1
| | | | | | | | | | | | | | | | A DSA driver may not provide the port_join_bridge and port_leave_bridge functions, so don't warn in such case. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * RDS-TCP: Reset tcp callbacks if re-using an outgoing socket in ↵Sowmini Varadhan2015-10-131-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rds_tcp_accept_one() Consider the following "duelling syn" sequence between two peers A and B: A B SYN1 --> <-- SYN2 SYN2ACK --> Note that the SYN/ACK has already been sent out by TCP before rds_tcp_accept_one() gets invoked as part of callbacks. If the inet_addr(A) is numerically less than inet_addr(B), the arbitration scheme in rds_tcp_accept_one() will prefer the TCP connection triggered by SYN1, and will send a CLOSE for the SYN2 (just after the SYN2ACK was sent). Since B also follows the same arbitration scheme, it will send the SYN-ACK for SYN1 that will set up a healthy ESTABLISHED connection on both sides. B will also get a CLOSE for SYN2, which should result in the cleanup of the TCP state machine for SYN2, but it should not trigger any stale RDS-TCP callbacks (such as ->writespace, ->state_change etc), that would disrupt the progress of the SYN2 based RDS-TCP connection. Thus the arbitration scheme in rds_tcp_accept_one() should restore rds_tcp callbacks for the winner before setting them up for the new accept socket, and also make sure that conn->c_outgoing is set to 0 so that we do not trigger any reconnect attempts on the passive side of the tcp socket in the future, in conformance with commit c82ac7e69efe ("net/rds: RDS-TCP: only initiate reconnect attempt on outgoing TCP socket.") Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * RDS: Invoke ->laddr_check() in rds_bind() for explicitly bound transports.Sowmini Varadhan2015-10-131-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | The IP address passed to rds_bind() should be vetted by the transport's ->laddr_check() for a previously bound transport. This needs to be done to avoid cases where, for example, the application has asked for an IB transport, but the IP address passed to bind is only usable on ethernet interfaces. Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * bridge: vlan: enforce no pvid flag in vlan rangesNikolay Aleksandrov2015-10-131-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | Currently it's possible for someone to send a vlan range to the kernel with the pvid flag set which will result in the pvid bouncing from a vlan to vlan and isn't correct, it also introduces problems for hardware where it doesn't make sense having more than 1 pvid. iproute2 already enforces this, so let's enforce it on kernel-side as well. Reported-by: Elad Raz <eladr@mellanox.com> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv6 route: use err pointers instead of returning pointer by referenceRoopa Prabhu2015-10-131-15/+17
| | | | | | | | | | | | | | | | This patch makes ip6_route_info_create return err pointer instead of returning the rt pointer by reference as suggested by Dave Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv6: Pass struct net into nf_ct_frag6_gatherEric W. Biederman2015-10-133-5/+4Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The function nf_ct_frag6_gather is called on both the input and the output paths of the networking stack. In particular ipv6_defrag which calls nf_ct_frag6_gather is called from both the the PRE_ROUTING chain on input and the LOCAL_OUT chain on output. The addition of a net parameter makes it explicit which network namespace the packets are being reassembled in, and removes the need for nf_ct_frag6_gather to guess. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv4: Pass struct net into ip_defrag and ip_check_defragEric W. Biederman2015-10-136-15/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | The function ip_defrag is called on both the input and the output paths of the networking stack. In particular conntrack when it is tracking outbound packets from the local machine calls ip_defrag. So add a struct net parameter and stop making ip_defrag guess which network namespace it needs to defragment packets in. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv4: Only compute net once in ip_call_ra_chainEric W. Biederman2015-10-131-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | ip_call_ra_chain is called early in the forwarding chain from ip_forward and ip_mr_input, which makes skb->dev the correct expression to get the input network device and dev_net(skb->dev) a correct expression for the network namespace the packet is being processed in. Compute the network namespace and store it in a variable to make the code clearer. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * packet: fix match_fanout_group()Eric Dumazet2015-10-131-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Recent TCP listener patches exposed a prior af_packet bug : match_fanout_group() blindly assumes it is always safe to cast sk to a packet socket to compare fanout with af_packet_priv But SYNACK packets can be sent while attached to request_sock, which are smaller than a "struct sock". We can read non existent memory and crash. Fixes: c0de08d04215 ("af_packet: don't emit packet on orig fanout group") Fixes: ca6fb0651883 ("tcp: attach SYNACK messages to request sockets instead of listener") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Eric Leblond <eric@regit.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv4/icmp: redirect messages can use the ingress daddr as sourcePaolo Abeni2015-10-132-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch allows configuring how the source address of ICMP redirect messages is selected; by default the old behaviour is retained, while setting icmp_redirects_use_orig_daddr force the usage of the destination address of the packet that caused the redirect. The new behaviour fits closely the RFC 5798 section 8.1.1, and fix the following scenario: Two machines are set up with VRRP to act as routers out of a subnet, they have IPs x.x.x.1/24 and x.x.x.2/24, with VRRP holding on to x.x.x.254/24. If a host in said subnet needs to get an ICMP redirect from the VRRP router, i.e. to reach a destination behind a different gateway, the source IP in the ICMP redirect is chosen as the primary IP on the interface that the packet arrived at, i.e. x.x.x.1 or x.x.x.2. The host will then ignore said redirect, due to RFC 1122 section 3.2.2.2, and will continue to use the wrong next-op. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * bridge: try switchdev op first in __vlan_vid_add/delJiri Pirko2015-10-131-36/+22Star
| | | | | | | | | | | | | | | | | | | | | | Some drivers need to implement both switchdev vlan ops and vid_add/kill ndos. For that to work in bridge code, we need to try switchdev op first when adding/deleting vlan id. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Ido Schimmel <idosch@mellanox.com> Acked-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: shrink struct sock and request_sock by 8 bytesEric Dumazet2015-10-137-17/+17
| | | | | | | | | | | | | | | | One 32bit hole is following skc_refcnt, use it. skc_incoming_cpu can also be an union for request_sock rcv_wnd. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: SO_INCOMING_CPU setsockopt() supportEric Dumazet2015-10-135-5/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SO_INCOMING_CPU as added in commit 2c8c56e15df3 was a getsockopt() command to fetch incoming cpu handling a particular TCP flow after accept() This commits adds setsockopt() support and extends SO_REUSEPORT selection logic : If a TCP listener or UDP socket has this option set, a packet is delivered to this socket only if CPU handling the packet matches the specified one. This allows to build very efficient TCP servers, using one listener per RX queue, as the associated TCP listener should only accept flows handled in softirq by the same cpu. This provides optimal NUMA behavior and keep cpu caches hot. Note that __inet_lookup_listener() still has to iterate over the list of all listeners. Following patch puts sk_refcnt in a different cache line to let this iteration hit only shared and read mostly cache lines. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * packet: support per-packet fwmark for af_packet sendmsgEdward Jee2015-10-131-1/+9
| | | | | | | | | | | | | | Signed-off-by: Edward Hyunkoo Jee <edjee@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * sock: support per-packet fwmarkEdward Jee2015-10-131-0/+26
| | | | | | | | | | | | | | | | | | | | | | It's useful to allow users to set fwmark for an individual packet, without changing the socket state. The function this patch adds in sock layer can be used by the protocols that need such a feature. Signed-off-by: Edward Hyunkoo Jee <edjee@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * bpf: enable non-root eBPF programsAlexei Starovoitov2015-10-131-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to let unprivileged users load and execute eBPF programs teach verifier to prevent pointer leaks. Verifier will prevent - any arithmetic on pointers (except R10+Imm which is used to compute stack addresses) - comparison of pointers (except if (map_value_ptr == 0) ... ) - passing pointers to helper functions - indirectly passing pointers in stack to helper functions - returning pointer from bpf program - storing pointers into ctx or maps Spill/fill of pointers into stack is allowed, but mangling of pointers stored in the stack or reading them byte by byte is not. Within bpf programs the pointers do exist, since programs need to be able to access maps, pass skb pointer to LD_ABS insns, etc but programs cannot pass such pointer values to the outside or obfuscate them. Only allow BPF_PROG_TYPE_SOCKET_FILTER unprivileged programs, so that socket filters (tcpdump), af_packet (quic acceleration) and future kcm can use it. tracing and tc cls/act program types still require root permissions, since tracing actually needs to be able to see all kernel pointers and tc is for root only. For example, the following unprivileged socket filter program is allowed: int bpf_prog1(struct __sk_buff *skb) { u32 index = load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol)); u64 *value = bpf_map_lookup_elem(&my_map, &index); if (value) *value += skb->len; return 0; } but the following program is not: int bpf_prog1(struct __sk_buff *skb) { u32 index = load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol)); u64 *value = bpf_map_lookup_elem(&my_map, &index); if (value) *value += (u64) skb; return 0; } since it would leak the kernel address into the map. Unprivileged socket filter bpf programs have access to the following helper functions: - map lookup/update/delete (but they cannot store kernel pointers into them) - get_random (it's already exposed to unprivileged user space) - get_smp_processor_id - tail_call into another socket filter program - ktime_get_ns The feature is controlled by sysctl kernel.unprivileged_bpf_disabled. This toggle defaults to off (0), but can be set true (1). Once true, bpf programs and maps cannot be accessed from unprivileged process, and the toggle cannot be set back to false. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-22 19:41:07 +0200