summaryrefslogtreecommitdiffstats
path: root/net/sched
AgeCommit message (Collapse)Author
2019-11-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
The only slightly tricky merge conflict was the netdevsim because the mutex locking fix overlapped a lot of driver reload reorganization. The rest were (relatively) trivial in nature. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-01net: cls_bpf: fix NULL deref on offload filter removalJakub Kicinski
Commit 401192113730 ("net: sched: refactor block offloads counter usage") missed the fact that either new prog or old prog may be NULL. Fixes: 401192113730 ("net: sched: refactor block offloads counter usage") Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30net: sched: update action implementations to support flagsVlad Buslov
Extend struct tc_action with new "tcfa_flags" field. Set the field in tcf_idr_create() function and provide new helper tcf_idr_create_from_flags() that derives 'cpustats' boolean from flags value. Update individual hardware-offloaded actions init() to pass their "flags" argument to new helper in order to skip percpu stats allocation when user requested it through flags. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30net: sched: extend TCA_ACT space with TCA_ACT_FLAGSVlad Buslov
Extend TCA_ACT space with nla_bitfield32 flags. Add TCA_ACT_FLAGS_NO_PERCPU_STATS as the only allowed flag. Parse the flags in tcf_action_init_1() and pass resulting value as additional argument to a_o->init(). Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30net: sched: modify stats helper functions to support regular statsVlad Buslov
Modify stats update helper functions introduced in previous patches in this series to fallback to regular tc_action->tcfa_{b|q}stats if cpu stats are not allocated for the action argument. If regular non-percpu allocated counters are in use, then obtain action tcfa_lock while modifying them. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30net: sched: don't expose action qstats to skb_tc_reinsert()Vlad Buslov
Previous commit introduced helper function for updating qstats and refactored set of actions to use the helpers, instead of modifying qstats directly. However, one of the affected action exposes its qstats to skb_tc_reinsert(), which then modifies it. Refactor skb_tc_reinsert() to return integer error code and don't increment overlimit qstats in case of error, and use the returned error code in tcf_mirred_act() to manually increment the overlimit counter with new helper function. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30net: sched: extract qstats update code into functionsVlad Buslov
Extract common code that increments cpu_qstats counters into standalone act API functions. Change hardware offloaded actions that use percpu counter allocation to use the new functions instead of accessing cpu_qstats directly. This commit doesn't change functionality. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30net: sched: extract bstats update code into functionVlad Buslov
Extract common code that increments cpu_bstats counter into standalone act API function. Change hardware offloaded actions that use percpu counter allocation to use the new function instead of incrementing cpu_bstats directly. This commit doesn't change functionality. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30net: sched: extract common action counters update code into functionVlad Buslov
Currently, all implementations of tc_action_ops->stats_update() callback have almost exactly the same implementation of counters update code (besides gact which also updates drop counter). In order to simplify support for using both percpu-allocated and regular action counters depending on run-time flag in following patches, extract action counters update code into standalone function in act API. This commit doesn't change functionality. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-25net: sch_generic: Use pfifo_fast as fallback scheduler for CAN hardwareVincent Prince
There is networking hardware that isn't based on Ethernet for layers 1 and 2. For example CAN. CAN is a multi-master serial bus standard for connecting Electronic Control Units [ECUs] also known as nodes. A frame on the CAN bus carries up to 8 bytes of payload. Frame corruption is detected by a CRC. However frame loss due to corruption is possible, but a quite unusual phenomenon. While fq_codel works great for TCP/IP, it doesn't for CAN. There are a lot of legacy protocols on top of CAN, which are not build with flow control or high CAN frame drop rates in mind. When using fq_codel, as soon as the queue reaches a certain delay based length, skbs from the head of the queue are silently dropped. Silently meaning that the user space using a send() or similar syscall doesn't get an error. However TCP's flow control algorithm will detect dropped packages and adjust the bandwidth accordingly. When using fq_codel and sending raw frames over CAN, which is the common use case, the user space thinks the package has been sent without problems, because send() returned without an error. pfifo_fast will drop skbs, if the queue length exceeds the maximum. But with this scheduler the skbs at the tail are dropped, an error (-ENOBUFS) is propagated to user space. So that the user space can slow down the package generation. On distributions, where fq_codel is made default via CONFIG_DEFAULT_NET_SCH during compile time, or set default during runtime with sysctl net.core.default_qdisc (see [1]), we get a bad user experience. In my test case with pfifo_fast, I can transfer thousands of million CAN frames without a frame drop. On the other hand with fq_codel there is more then one lost CAN frame per thousand frames. As pointed out fq_codel is not suited for CAN hardware, so this patch changes attach_one_default_qdisc() to use pfifo_fast for "ARPHRD_CAN" network devices. During transition of a netdev from down to up state the default queuing discipline is attached by attach_default_qdiscs() with the help of attach_one_default_qdisc(). This patch modifies attach_one_default_qdisc() to attach the pfifo_fast (pfifo_fast_ops) if the network device type is "ARPHRD_CAN". [1] https://github.com/systemd/systemd/issues/9194 Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Vincent Prince <vincent.prince.fr@gmail.com> Acked-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-25net: sch_generic: Use pfifo_fast as fallback scheduler for CAN hardwareVincent Prince
There is networking hardware that isn't based on Ethernet for layers 1 and 2. For example CAN. CAN is a multi-master serial bus standard for connecting Electronic Control Units [ECUs] also known as nodes. A frame on the CAN bus carries up to 8 bytes of payload. Frame corruption is detected by a CRC. However frame loss due to corruption is possible, but a quite unusual phenomenon. While fq_codel works great for TCP/IP, it doesn't for CAN. There are a lot of legacy protocols on top of CAN, which are not build with flow control or high CAN frame drop rates in mind. When using fq_codel, as soon as the queue reaches a certain delay based length, skbs from the head of the queue are silently dropped. Silently meaning that the user space using a send() or similar syscall doesn't get an error. However TCP's flow control algorithm will detect dropped packages and adjust the bandwidth accordingly. When using fq_codel and sending raw frames over CAN, which is the common use case, the user space thinks the package has been sent without problems, because send() returned without an error. pfifo_fast will drop skbs, if the queue length exceeds the maximum. But with this scheduler the skbs at the tail are dropped, an error (-ENOBUFS) is propagated to user space. So that the user space can slow down the package generation. On distributions, where fq_codel is made default via CONFIG_DEFAULT_NET_SCH during compile time, or set default during runtime with sysctl net.core.default_qdisc (see [1]), we get a bad user experience. In my test case with pfifo_fast, I can transfer thousands of million CAN frames without a frame drop. On the other hand with fq_codel there is more then one lost CAN frame per thousand frames. As pointed out fq_codel is not suited for CAN hardware, so this patch changes attach_one_default_qdisc() to use pfifo_fast for "ARPHRD_CAN" network devices. During transition of a netdev from down to up state the default queuing discipline is attached by attach_default_qdiscs() with the help of attach_one_default_qdisc(). This patch modifies attach_one_default_qdisc() to attach the pfifo_fast (pfifo_fast_ops) if the network device type is "ARPHRD_CAN". [1] https://github.com/systemd/systemd/issues/9194 Signed-off-by: Vincent Prince <vincent.prince.fr@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-24net: core: add generic lockdep keysTaehee Yoo
Some interface types could be nested. (VLAN, BONDING, TEAM, MACSEC, MACVLAN, IPVLAN, VIRT_WIFI, VXLAN, etc..) These interface types should set lockdep class because, without lockdep class key, lockdep always warn about unexisting circular locking. In the current code, these interfaces have their own lockdep class keys and these manage itself. So that there are so many duplicate code around the /driver/net and /net/. This patch adds new generic lockdep keys and some helper functions for it. This patch does below changes. a) Add lockdep class keys in struct net_device - qdisc_running, xmit, addr_list, qdisc_busylock - these keys are used as dynamic lockdep key. b) When net_device is being allocated, lockdep keys are registered. - alloc_netdev_mqs() c) When net_device is being free'd llockdep keys are unregistered. - free_netdev() d) Add generic lockdep key helper function - netdev_register_lockdep_key() - netdev_unregister_lockdep_key() - netdev_update_lockdep_key() e) Remove unnecessary generic lockdep macro and functions f) Remove unnecessary lockdep code of each interfaces. After this patch, each interface modules don't need to maintain their lockdep keys. Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-23net/flow_dissector: switch to siphashEric Dumazet
UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Berger <jonathann1@walla.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-22fq_codel: do not include <linux/jhash.h>Eric Dumazet
Since commit 342db221829f ("sched: Call skb_get_hash_perturb in sch_fq_codel") we no longer need anything from this file. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-22net: sched: taprio: fix -Wmissing-prototypes warningsYi Wang
We get one warnings when build kernel W=1: net/sched/sch_taprio.c:1155:6: warning: no previous prototype for ‘taprio_offload_config_changed’ [-Wmissing-prototypes] Make the function static to fix this. Fixes: 9c66d1564676 ("taprio: Add support for hardware offloading") Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-21net/sched: act_police: re-use tcf_tm_dump()Davide Caratti
Use tcf_tm_dump(), instead of an open coded variant (no functional change in this patch). Signed-off-by: Davide Caratti <dcaratti@redhat.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Several cases of overlapping changes which were for the most part trivially resolvable. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-19net: netem: correct the parent's backlog when corrupted packet was droppedJakub Kicinski
If packet corruption failed we jump to finish_segs and return NET_XMIT_SUCCESS. Seeing success will make the parent qdisc increment its backlog, that's incorrect - we need to return NET_XMIT_DROP. Fixes: 6071bd1aa13e ("netem: Segment GSO packets on enqueue") Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-19net: netem: fix error path for corrupted GSO framesJakub Kicinski
To corrupt a GSO frame we first perform segmentation. We then proceed using the first segment instead of the full GSO skb and requeue the rest of the segments as separate packets. If there are any issues with processing the first segment we still want to process the rest, therefore we jump to the finish_segs label. Commit 177b8007463c ("net: netem: fix backlog accounting for corrupted GSO frames") started using the pointer to the first segment in the "rest of segments processing", but as mentioned above the first segment may had already been freed at this point. Backlog corrections for parent qdiscs have to be adjusted. Fixes: 177b8007463c ("net: netem: fix backlog accounting for corrupted GSO frames") Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Reported-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17net: sched: Avoid using yield() in a busy waiting loopMarc Kleine-Budde
With threaded interrupts enabled, the interrupt thread runs as SCHED_RR with priority 50. If a user application with a higher priority preempts the interrupt thread and tries to shutdown the network interface then it will loop forever. The kernel will spin in the loop waiting for the device to become idle and the scheduler will never consider the interrupt thread because its priority is lower. Avoid the problem by sleeping for a jiffy giving other tasks, including the interrupt thread, a chance to run and make progress. In the original thread it has been suggested to use wait_event() and properly waiting for the state to occur. DaveM explained that this would require to add expensive checks in the fast paths of packet processing. Link: https://lkml.kernel.org/r/1393976987-23555-1-git-send-email-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> [bigeasy: Rewrite commit message, add comment, use schedule_timeout_uninterruptible()] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15sched: etf: Fix ordering of packets with same txtimeVinicius Costa Gomes
When a application sends many packets with the same txtime, they may be transmitted out of order (different from the order in which they were enqueued). This happens because when inserting elements into the tree, when the txtime of two packets are the same, the new packet is inserted at the left side of the tree, causing the reordering. The only effect of this change should be that packets with the same txtime will be transmitted in the order they are enqueued. The application in question (the AVTP GStreamer plugin, still in development) is sending video traffic, in which each video frame have a single presentation time, the problem is that when packetizing, multiple packets end up with the same txtime. The receiving side was rejecting packets because they were being received out of order. Fixes: 25db26a91364 ("net/sched: Introduce the ETF Qdisc") Reported-by: Ederson de Souza <ederson.desouza@intel.com> Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15net: avoid potential infinite loop in tc_ctl_action()Eric Dumazet
tc_ctl_action() has the ability to loop forever if tcf_action_add() returns -EAGAIN. This special case has been done in case a module needed to be loaded, but it turns out that tcf_add_notify() could also return -EAGAIN if the socket sk_rcvbuf limit is hit. We need to separate the two cases, and only loop for the module loading case. While we are at it, add a limit of 10 attempts since unbounded loops are always scary. syzbot repro was something like : socket(PF_NETLINK, SOCK_RAW|SOCK_NONBLOCK, NETLINK_ROUTE) = 3 write(3, ..., 38) = 38 setsockopt(3, SOL_SOCKET, SO_RCVBUF, [0], 4) = 0 sendmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{..., 388}], msg_controllen=0, msg_flags=0x10}, ...) NMI backtrace for cpu 0 CPU: 0 PID: 1054 Comm: khungtaskd Not tainted 5.4.0-rc1+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0x9d0/0xef0 kernel/hung_task.c:289 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8859 Comm: syz-executor910 Not tainted 5.4.0-rc1+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:751 [inline] RIP: 0010:lockdep_hardirqs_off+0x1df/0x2e0 kernel/locking/lockdep.c:3453 Code: 5c 08 00 00 5b 41 5c 41 5d 5d c3 48 c7 c0 58 1d f3 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 d3 00 00 00 <48> 83 3d 21 9e 99 07 00 0f 84 b9 00 00 00 9c 58 0f 1f 44 00 00 f6 RSP: 0018:ffff8880a6f3f1b8 EFLAGS: 00000046 RAX: 1ffffffff11e63ab RBX: ffff88808c9c6080 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff88808c9c6914 RBP: ffff8880a6f3f1d0 R08: ffff88808c9c6080 R09: fffffbfff16be5d1 R10: fffffbfff16be5d0 R11: 0000000000000003 R12: ffffffff8746591f R13: ffff88808c9c6080 R14: ffffffff8746591f R15: 0000000000000003 FS: 00000000011e4880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000000a8920000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_hardirqs_off+0x62/0x240 kernel/trace/trace_preemptirq.c:45 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] _raw_spin_lock_irqsave+0x6f/0xcd kernel/locking/spinlock.c:159 __wake_up_common_lock+0xc8/0x150 kernel/sched/wait.c:122 __wake_up+0xe/0x10 kernel/sched/wait.c:142 netlink_unlock_table net/netlink/af_netlink.c:466 [inline] netlink_unlock_table net/netlink/af_netlink.c:463 [inline] netlink_broadcast_filtered+0x705/0xb80 net/netlink/af_netlink.c:1514 netlink_broadcast+0x3a/0x50 net/netlink/af_netlink.c:1534 rtnetlink_send+0xdd/0x110 net/core/rtnetlink.c:714 tcf_add_notify net/sched/act_api.c:1343 [inline] tcf_action_add+0x243/0x370 net/sched/act_api.c:1362 tc_ctl_action+0x3b5/0x4bc net/sched/act_api.c:1410 rtnetlink_rcv_msg+0x463/0xb00 net/core/rtnetlink.c:5386 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5404 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 ___sys_sendmsg+0x803/0x920 net/socket.c:2311 __sys_sendmsg+0x105/0x1d0 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2363 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440939 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot+cf0adbb9c28c8866c788@syzkaller.appspotmail.com Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15net_sched: sch_fq: remove one obsolete check in fq_dequeue()Eric Dumazet
After commit eeb84aa0d0aff ("net_sched: sch_fq: do not assume EDT packets are ordered"), all skbs get a non zero time_to_send in flow_queue_add() This means @time_next_packet variable in fq_dequeue() can no longer be zero. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15net/sched: fix corrupted L2 header with MPLS 'push' and 'pop' actionsDavide Caratti
the following script: # tc qdisc add dev eth0 clsact # tc filter add dev eth0 egress protocol ip matchall \ > action mpls push protocol mpls_uc label 0x355aa bos 1 causes corruption of all IP packets transmitted by eth0. On TC egress, we can't rely on the value of skb->mac_len, because it's 0 and a MPLS 'push' operation will result in an overwrite of the first 4 octets in the packet L2 header (e.g. the Destination Address if eth0 is an Ethernet); the same error pattern is present also in the MPLS 'pop' operation. Fix this error in act_mpls data plane, computing 'mac_len' as the difference between the network header and the mac header (when not at TC ingress), and use it in MPLS 'push'/'pop' core functions. v2: unbreak 'make htmldocs' because of missing documentation of 'mac_len' in skb_mpls_pop(), reported by kbuild test robot CC: Lorenzo Bianconi <lorenzo@kernel.org> Fixes: 2a2ea50870ba ("net: sched: add mpls manipulation actions to TC") Reviewed-by: Simon Horman <simon.horman@netronome.com> Acked-by: John Hurley <john.hurley@netronome.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: annotate sk->sk_wmem_queued lockless readsEric Dumazet
For the sake of tcp_poll(), there are few places where we fetch sk->sk_wmem_queued while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. sk_wmem_queued_add() helper is added so that we can in the future convert to ADD_ONCE() or equivalent if/when available. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-09net: annotate sk->sk_rcvlowat lockless readsEric Dumazet
sock_rcvlowat() or int_sk_rcvlowat() might be called without the socket lock for example from tcp_poll(). Use READ_ONCE() to document the fact that other cpus might change sk->sk_rcvlowat under us and avoid KCSAN splats. Use WRITE_ONCE() on write sides too. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-09act_mirred: Fix mirred_init_module error handlingYueHaibing
If tcf_register_action failed, mirred_device_notifier should be unregistered. Fixes: 3b87956ea645 ("net sched: fix race in mirred device removal") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-09net: taprio: Fix returning EINVAL when configuring without flagsVinicius Costa Gomes
When configuring a taprio instance if "flags" is not specified (or it's zero), taprio currently replies with an "Invalid argument" error. So, set the return value to zero after we are done with all the checks. Fixes: 9c66d1564676 ("taprio: Add support for hardware offloading") Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com> Acked-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-08net_sched: fix backward compatibility for TCA_ACT_KINDCong Wang
For TCA_ACT_KIND, we have to keep the backward compatibility too, and rely on nla_strlcpy() to check and terminate the string with a NUL. Note for TC actions, nla_strcmp() is already used to compare kind strings, so we don't need to fix other places. Fixes: 199ce850ce11 ("net_sched: add policy validation for action attributes") Reported-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-08net_sched: fix backward compatibility for TCA_KINDCong Wang
Marcelo noticed a backward compatibility issue of TCA_KIND after we move from NLA_STRING to NLA_NUL_STRING, so it is probably too late to change it. Instead, to make everyone happy, we can just insert a NUL to terminate the string with nla_strlcpy() like we do for TC actions. Fixes: 62794fc4fbf5 ("net_sched: add max len check for TCA_KIND") Reported-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
2019-10-04sch_dsmark: fix potential NULL deref in dsmark_init()Eric Dumazet
Make sure TCA_DSMARK_INDICES was provided by the user. syzbot reported : kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 8799 Comm: syz-executor235 Not tainted 5.3.0+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:nla_get_u16 include/net/netlink.h:1501 [inline] RIP: 0010:dsmark_init net/sched/sch_dsmark.c:364 [inline] RIP: 0010:dsmark_init+0x193/0x640 net/sched/sch_dsmark.c:339 Code: 85 db 58 0f 88 7d 03 00 00 e8 e9 1a ac fb 48 8b 9d 70 ff ff ff 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 04 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 ca RSP: 0018:ffff88809426f3b8 EFLAGS: 00010247 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff85c6eb09 RDX: 0000000000000000 RSI: ffffffff85c6eb17 RDI: 0000000000000004 RBP: ffff88809426f4b0 R08: ffff88808c4085c0 R09: ffffed1015d26159 R10: ffffed1015d26158 R11: ffff8880ae930ac7 R12: ffff8880a7e96940 R13: dffffc0000000000 R14: ffff88809426f8c0 R15: 0000000000000000 FS: 0000000001292880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000080 CR3: 000000008ca1b000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: qdisc_create+0x4ee/0x1210 net/sched/sch_api.c:1237 tc_modify_qdisc+0x524/0x1c50 net/sched/sch_api.c:1653 rtnetlink_rcv_msg+0x463/0xb00 net/core/rtnetlink.c:5223 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5241 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 ___sys_sendmsg+0x803/0x920 net/socket.c:2311 __sys_sendmsg+0x105/0x1d0 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2363 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440369 Fixes: 758cc43c6d73 ("[PKT_SCHED]: Fix dsmark to apply changes consistent") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-02net_sched: remove need_resched() from qdisc_run()Eric Dumazet
The introduction of this schedule point was done in commit 2ba2506ca7ca ("[NET]: Add preemption point in qdisc_run") at a time the loop was not bounded. Then later in commit d5b8aa1d246f ("net_sched: fix dequeuer fairness") we added a limit on the number of packets. Now is the time to remove the schedule point, since the default limit of 64 packets matches the number of packets a typical NAPI poll can process in a row. This solves a latency problem for most TCP receivers under moderate load : 1) host receives a packet. NET_RX_SOFTIRQ is raised by NIC hard IRQ handler 2) __do_softirq() does its first loop, handling NET_RX_SOFTIRQ and calling the driver napi->loop() function 3) TCP stores the skb in socket receive queue: 4) TCP calls sk->sk_data_ready() and wakeups a user thread waiting for EPOLLIN (as a result, need_resched() might now be true) 5) TCP cooks an ACK and sends it. 6) qdisc_run() processes one packet from qdisc, and sees need_resched(), this raises NET_TX_SOFTIRQ (even if there are no more packets in the qdisc) Then we go back to the __do_softirq() in 2), and we see that new softirqs were raised. Since need_resched() is true, we end up waking ksoftirqd in this path : if (pending) { if (time_before(jiffies, end) && !need_resched() && --max_restart) goto restart; wakeup_softirqd(); } So we have many wakeups of ksoftirqd kernel threads, and more calls to qdisc_run() with associated lock overhead. Note that another way to solve the issue would be to change TCP to first send the ACK packet, then signal the EPOLLIN, but this changes P99 latencies, as sending the ACK packet can add a long delay. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-01net: sched: cbs: Avoid division by zero when calculating the port rateVladimir Oltean
As explained in the "net: sched: taprio: Avoid division by zero on invalid link speed" commit, it is legal for the ethtool API to return zero as a link speed. So guard against it to ensure we don't perform a division by zero in kernel. Fixes: e0a7683d30e9 ("net/sched: cbs: fix port_rate miscalculation") Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-01net: sched: taprio: Avoid division by zero on invalid link speedVladimir Oltean
The check in taprio_set_picos_per_byte is currently not robust enough and will trigger this division by zero, due to e.g. PHYLINK not setting kset->base.speed when there is no PHY connected: [ 27.109992] Division by zero in kernel. [ 27.113842] CPU: 1 PID: 198 Comm: tc Not tainted 5.3.0-rc5-01246-gc4006b8c2637-dirty #212 [ 27.121974] Hardware name: Freescale LS1021A [ 27.126234] [<c03132e0>] (unwind_backtrace) from [<c030d8b8>] (show_stack+0x10/0x14) [ 27.133938] [<c030d8b8>] (show_stack) from [<c10b21b0>] (dump_stack+0xb0/0xc4) [ 27.141124] [<c10b21b0>] (dump_stack) from [<c10af97c>] (Ldiv0_64+0x8/0x18) [ 27.148052] [<c10af97c>] (Ldiv0_64) from [<c0700260>] (div64_u64+0xcc/0xf0) [ 27.154978] [<c0700260>] (div64_u64) from [<c07002d0>] (div64_s64+0x4c/0x68) [ 27.161993] [<c07002d0>] (div64_s64) from [<c0f3d890>] (taprio_set_picos_per_byte+0xe8/0xf4) [ 27.170388] [<c0f3d890>] (taprio_set_picos_per_byte) from [<c0f3f614>] (taprio_change+0x668/0xcec) [ 27.179302] [<c0f3f614>] (taprio_change) from [<c0f2bc24>] (qdisc_create+0x1fc/0x4f4) [ 27.187091] [<c0f2bc24>] (qdisc_create) from [<c0f2c0c8>] (tc_modify_qdisc+0x1ac/0x6f8) [ 27.195055] [<c0f2c0c8>] (tc_modify_qdisc) from [<c0ee9604>] (rtnetlink_rcv_msg+0x268/0x2dc) [ 27.203449] [<c0ee9604>] (rtnetlink_rcv_msg) from [<c0f4fef0>] (netlink_rcv_skb+0xe0/0x114) [ 27.211756] [<c0f4fef0>] (netlink_rcv_skb) from [<c0f4f6cc>] (netlink_unicast+0x1b4/0x22c) [ 27.219977] [<c0f4f6cc>] (netlink_unicast) from [<c0f4fa84>] (netlink_sendmsg+0x284/0x340) [ 27.228198] [<c0f4fa84>] (netlink_sendmsg) from [<c0eae5fc>] (sock_sendmsg+0x14/0x24) [ 27.235988] [<c0eae5fc>] (sock_sendmsg) from [<c0eaedf8>] (___sys_sendmsg+0x214/0x228) [ 27.243863] [<c0eaedf8>] (___sys_sendmsg) from [<c0eb015c>] (__sys_sendmsg+0x50/0x8c) [ 27.251652] [<c0eb015c>] (__sys_sendmsg) from [<c0301000>] (ret_fast_syscall+0x0/0x54) [ 27.259524] Exception stack(0xe8045fa8 to 0xe8045ff0) [ 27.264546] 5fa0: b6f608c8 000000f8 00000003 bed7e2f0 00000000 00000000 [ 27.272681] 5fc0: b6f608c8 000000f8 004ce54c 00000128 5d3ce8c7 00000000 00000026 00505c9c [ 27.280812] 5fe0: 00000070 bed7e298 004ddd64 b6dd1e64 Russell King points out that the ethtool API says zero is a valid return value of __ethtool_get_link_ksettings: * If it is enabled then they are read-only; if the link * is up they represent the negotiated link mode; if the link is down, * the speed is 0, %SPEED_UNKNOWN or the highest enabled speed and * @duplex is %DUPLEX_UNKNOWN or the best enabled duplex mode. So, it seems that taprio is not following the API... I'd suggest either fixing taprio, or getting agreement to change the ethtool API. The chosen path was to fix taprio. Fixes: 7b9eba7ba0c1 ("net/sched: taprio: fix picos_per_byte miscalculation") Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-30net: sched: taprio: Fix potential integer overflow in taprio_set_picos_per_byteVladimir Oltean
The speed divisor is used in a context expecting an s64, but it is evaluated using 32-bit arithmetic. To avoid that happening, instead of multiplying by 1,000,000 in the first place, simplify the fraction and do a standard 32 bit division instead. Fixes: f04b514c0ce2 ("taprio: Set default link speed to 10 Mbps in taprio_set_picos_per_byte") Reported-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-30sch_cbq: validate TCA_CBQ_WRROPT to avoid crashEric Dumazet
syzbot reported a crash in cbq_normalize_quanta() caused by an out of range cl->priority. iproute2 enforces this check, but malicious users do not. kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN PTI Modules linked in: CPU: 1 PID: 26447 Comm: syz-executor.1 Not tainted 5.3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:cbq_normalize_quanta.part.0+0x1fd/0x430 net/sched/sch_cbq.c:902 RSP: 0018:ffff8801a5c333b0 EFLAGS: 00010206 RAX: 0000000020000003 RBX: 00000000fffffff8 RCX: ffffc9000712f000 RDX: 00000000000043bf RSI: ffffffff83be8962 RDI: 0000000100000018 RBP: ffff8801a5c33420 R08: 000000000000003a R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000002ef R13: ffff88018da95188 R14: dffffc0000000000 R15: 0000000000000015 FS: 00007f37d26b1700(0000) GS:ffff8801dad00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004c7cec CR3: 00000001bcd0a006 CR4: 00000000001626f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: [<ffffffff83be9d57>] cbq_normalize_quanta include/net/pkt_sched.h:27 [inline] [<ffffffff83be9d57>] cbq_addprio net/sched/sch_cbq.c:1097 [inline] [<ffffffff83be9d57>] cbq_set_wrr+0x2d7/0x450 net/sched/sch_cbq.c:1115 [<ffffffff83bee8a7>] cbq_change_class+0x987/0x225b net/sched/sch_cbq.c:1537 [<ffffffff83b96985>] tc_ctl_tclass+0x555/0xcd0 net/sched/sch_api.c:2329 [<ffffffff83a84655>] rtnetlink_rcv_msg+0x485/0xc10 net/core/rtnetlink.c:5248 [<ffffffff83cadf0a>] netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2510 [<ffffffff83a7db6d>] rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5266 [<ffffffff83cac2c6>] netlink_unicast_kernel net/netlink/af_netlink.c:1324 [inline] [<ffffffff83cac2c6>] netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1350 [<ffffffff83cacd4a>] netlink_sendmsg+0x89a/0xd50 net/netlink/af_netlink.c:1939 [<ffffffff8399d46e>] sock_sendmsg_nosec net/socket.c:673 [inline] [<ffffffff8399d46e>] sock_sendmsg+0x12e/0x170 net/socket.c:684 [<ffffffff8399f1fd>] ___sys_sendmsg+0x81d/0x960 net/socket.c:2359 [<ffffffff839a2d05>] __sys_sendmsg+0x105/0x1d0 net/socket.c:2397 [<ffffffff839a2df9>] SYSC_sendmsg net/socket.c:2406 [inline] [<ffffffff839a2df9>] SyS_sendmsg+0x29/0x30 net/socket.c:2404 [<ffffffff8101ccc8>] do_syscall_64+0x528/0x770 arch/x86/entry/common.c:305 [<ffffffff84400091>] entry_SYSCALL_64_after_hwframe+0x42/0xb7 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-27net/sched: Set default of CONFIG_NET_TC_SKB_EXT to NPaul Blakey
This a new feature, it is preferred that it defaults to N. We will probe the feature support from userspace before actually using it. Fixes: 95a7233c452a ('net: openvswitch: Set OvS recirc_id from tc chain index') Signed-off-by: Paul Blakey <paulb@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-27net: sched: sch_sfb: don't call qdisc_put() while holding tree lockVlad Buslov
Recent changes that removed rtnl dependency from rules update path of tc also made tcf_block_put() function sleeping. This function is called from ops->destroy() of several Qdisc implementations, which in turn is called by qdisc_put(). Some Qdiscs call qdisc_put() while holding sch tree spinlock, which results sleeping-while-atomic BUG. Steps to reproduce for sfb: tc qdisc add dev ens1f0 handle 1: root sfb tc qdisc add dev ens1f0 parent 1:10 handle 50: sfq perturb 10 tc qdisc change dev ens1f0 root handle 1: sfb Resulting dmesg: [ 7265.938717] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909 [ 7265.940152] in_atomic(): 1, irqs_disabled(): 0, pid: 28579, name: tc [ 7265.941455] INFO: lockdep is turned off. [ 7265.942744] CPU: 11 PID: 28579 Comm: tc Tainted: G W 5.3.0-rc8+ #721 [ 7265.944065] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 7265.945396] Call Trace: [ 7265.946709] dump_stack+0x85/0xc0 [ 7265.947994] ___might_sleep.cold+0xac/0xbc [ 7265.949282] __mutex_lock+0x5b/0x960 [ 7265.950543] ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0 [ 7265.951803] ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0 [ 7265.953022] tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0 [ 7265.954248] tcf_block_put_ext.part.0+0x21/0x50 [ 7265.955478] tcf_block_put+0x50/0x70 [ 7265.956694] sfq_destroy+0x15/0x50 [sch_sfq] [ 7265.957898] qdisc_destroy+0x5f/0x160 [ 7265.959099] sfb_change+0x175/0x330 [sch_sfb] [ 7265.960304] tc_modify_qdisc+0x324/0x840 [ 7265.961503] rtnetlink_rcv_msg+0x170/0x4b0 [ 7265.962692] ? netlink_deliver_tap+0x95/0x400 [ 7265.963876] ? rtnl_dellink+0x2d0/0x2d0 [ 7265.965064] netlink_rcv_skb+0x49/0x110 [ 7265.966251] netlink_unicast+0x171/0x200 [ 7265.967427] netlink_sendmsg+0x224/0x3f0 [ 7265.968595] sock_sendmsg+0x5e/0x60 [ 7265.969753] ___sys_sendmsg+0x2ae/0x330 [ 7265.970916] ? ___sys_recvmsg+0x159/0x1f0 [ 7265.972074] ? do_wp_page+0x9c/0x790 [ 7265.973233] ? __handle_mm_fault+0xcd3/0x19e0 [ 7265.974407] __sys_sendmsg+0x59/0xa0 [ 7265.975591] do_syscall_64+0x5c/0xb0 [ 7265.976753] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 7265.977938] RIP: 0033:0x7f229069f7b8 [ 7265.979117] Code: 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 8f 0c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 89 5 4 [ 7265.981681] RSP: 002b:00007ffd7ed2d158 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 7265.983001] RAX: ffffffffffffffda RBX: 000000005d813ca1 RCX: 00007f229069f7b8 [ 7265.984336] RDX: 0000000000000000 RSI: 00007ffd7ed2d1c0 RDI: 0000000000000003 [ 7265.985682] RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000165c9a0 [ 7265.987021] R10: 0000000000404eda R11: 0000000000000246 R12: 0000000000000001 [ 7265.988309] R13: 000000000047f640 R14: 0000000000000000 R15: 0000000000000000 In sfb_change() function use qdisc_purge_queue() instead of qdisc_tree_flush_backlog() to properly reset old child Qdisc and save pointer to it into local temporary variable. Put reference to Qdisc after sch tree lock is released in order not to call potentially sleeping cls API in atomic section. This is safe to do because Qdisc has already been reset by qdisc_purge_queue() inside sch tree lock critical section. Reported-by: syzbot+ac54455281db908c581e@syzkaller.appspotmail.com Fixes: c266f64dbfa2 ("net: sched: protect block state with mutex") Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-27net: sched: multiq: don't call qdisc_put() while holding tree lockVlad Buslov
Recent changes that removed rtnl dependency from rules update path of tc also made tcf_block_put() function sleeping. This function is called from ops->destroy() of several Qdisc implementations, which in turn is called by qdisc_put(). Some Qdiscs call qdisc_put() while holding sch tree spinlock, which results sleeping-while-atomic BUG. Steps to reproduce for multiq: tc qdisc add dev ens1f0 root handle 1: multiq tc qdisc add dev ens1f0 parent 1:10 handle 50: sfq perturb 10 ethtool -L ens1f0 combined 2 tc qdisc change dev ens1f0 root handle 1: multiq Resulting dmesg: [ 5539.419344] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909 [ 5539.420945] in_atomic(): 1, irqs_disabled(): 0, pid: 27658, name: tc [ 5539.422435] INFO: lockdep is turned off. [ 5539.423904] CPU: 21 PID: 27658 Comm: tc Tainted: G W 5.3.0-rc8+ #721 [ 5539.425400] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 5539.426911] Call Trace: [ 5539.428380] dump_stack+0x85/0xc0 [ 5539.429823] ___might_sleep.cold+0xac/0xbc [ 5539.431262] __mutex_lock+0x5b/0x960 [ 5539.432682] ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0 [ 5539.434103] ? __nla_validate_parse+0x51/0x840 [ 5539.435493] ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0 [ 5539.436903] tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0 [ 5539.438327] tcf_block_put_ext.part.0+0x21/0x50 [ 5539.439752] tcf_block_put+0x50/0x70 [ 5539.441165] sfq_destroy+0x15/0x50 [sch_sfq] [ 5539.442570] qdisc_destroy+0x5f/0x160 [ 5539.444000] multiq_tune+0x14a/0x420 [sch_multiq] [ 5539.445421] tc_modify_qdisc+0x324/0x840 [ 5539.446841] rtnetlink_rcv_msg+0x170/0x4b0 [ 5539.448269] ? netlink_deliver_tap+0x95/0x400 [ 5539.449691] ? rtnl_dellink+0x2d0/0x2d0 [ 5539.451116] netlink_rcv_skb+0x49/0x110 [ 5539.452522] netlink_unicast+0x171/0x200 [ 5539.453914] netlink_sendmsg+0x224/0x3f0 [ 5539.455304] sock_sendmsg+0x5e/0x60 [ 5539.456686] ___sys_sendmsg+0x2ae/0x330 [ 5539.458071] ? ___sys_recvmsg+0x159/0x1f0 [ 5539.459461] ? do_wp_page+0x9c/0x790 [ 5539.460846] ? __handle_mm_fault+0xcd3/0x19e0 [ 5539.462263] __sys_sendmsg+0x59/0xa0 [ 5539.463661] do_syscall_64+0x5c/0xb0 [ 5539.465044] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 5539.466454] RIP: 0033:0x7f1fe08177b8 [ 5539.467863] Code: 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 8f 0c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 89 5 4 [ 5539.470906] RSP: 002b:00007ffe812de5d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 5539.472483] RAX: ffffffffffffffda RBX: 000000005d8135e3 RCX: 00007f1fe08177b8 [ 5539.474069] RDX: 0000000000000000 RSI: 00007ffe812de640 RDI: 0000000000000003 [ 5539.475655] RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000182e9b0 [ 5539.477203] R10: 0000000000404eda R11: 0000000000000246 R12: 0000000000000001 [ 5539.478699] R13: 000000000047f640 R14: 0000000000000000 R15: 0000000000000000 Rearrange locking in multiq_tune() in following ways: - In loop that removes Qdiscs from disabled queues, call qdisc_purge_queue() instead of qdisc_tree_flush_backlog() on Qdisc that is being destroyed. Save the Qdisc in temporary allocated array and call qdisc_put() on each element of the array after sch tree lock is released. This is safe to do because Qdiscs have already been reset by qdisc_purge_queue() inside sch tree lock critical section. - Do the same change for second loop that initializes Qdiscs for newly enabled queues in multiq_tune() function. Since sch tree lock is obtained and released on each iteration of this loop, just call qdisc_put() directly outside of critical section. Don't verify that old Qdisc is not noop_qdisc before releasing reference to it because such check is already performed by qdisc_put*() functions. Fixes: c266f64dbfa2 ("net: sched: protect block state with mutex") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-27net: sched: sch_htb: don't call qdisc_put() while holding tree lockVlad Buslov
Recent changes that removed rtnl dependency from rules update path of tc also made tcf_block_put() function sleeping. This function is called from ops->destroy() of several Qdisc implementations, which in turn is called by qdisc_put(). Some Qdiscs call qdisc_put() while holding sch tree spinlock, which results sleeping-while-atomic BUG. Steps to reproduce for htb: tc qdisc add dev ens1f0 root handle 1: htb default 12 tc class add dev ens1f0 parent 1: classid 1:1 htb rate 100kbps ceil 100kbps tc qdisc add dev ens1f0 parent 1:1 handle 40: sfq perturb 10 tc class add dev ens1f0 parent 1:1 classid 1:2 htb rate 100kbps ceil 100kbps Resulting dmesg: [ 4791.148551] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:9