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* net: sched: fix possible crash in tcf_action_destroy()Eric Dumazet2019-10-051-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 3d66b89c30f9220a72e92847768fc8ba4d027d88 ] If the allocation done in tcf_exts_init() failed, we end up with a NULL pointer in exts->actions. kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 8198 Comm: syz-executor.3 Not tainted 5.3.0-rc8+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:tcf_action_destroy+0x71/0x160 net/sched/act_api.c:705 Code: c3 08 44 89 ee e8 4f cb bb fb 41 83 fd 20 0f 84 c9 00 00 00 e8 c0 c9 bb fb 48 89 d8 48 b9 00 00 00 00 00 fc ff df 48 c1 e8 03 <80> 3c 08 00 0f 85 c0 00 00 00 4c 8b 33 4d 85 f6 0f 84 9d 00 00 00 RSP: 0018:ffff888096e16ff0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: dffffc0000000000 RDX: 0000000000040000 RSI: ffffffff85b6ab30 RDI: 0000000000000000 RBP: ffff888096e17020 R08: ffff8880993f6140 R09: fffffbfff11cae67 R10: fffffbfff11cae66 R11: ffffffff88e57333 R12: 0000000000000000 R13: 0000000000000000 R14: ffff888096e177a0 R15: 0000000000000001 FS: 00007f62bc84a700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000758040 CR3: 0000000088b64000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tcf_exts_destroy+0x38/0xb0 net/sched/cls_api.c:3030 tcindex_set_parms+0xf7f/0x1e50 net/sched/cls_tcindex.c:488 tcindex_change+0x230/0x318 net/sched/cls_tcindex.c:519 tc_new_tfilter+0xa4b/0x1c70 net/sched/cls_api.c:2152 rtnetlink_rcv_msg+0x838/0xb00 net/core/rtnetlink.c:5214 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+0x3e2/0x920 net/socket.c:2311 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2413 __do_sys_sendmmsg net/socket.c:2442 [inline] Fixes: 90b73b77d08e ("net: sched: change action API to use array of pointers to actions") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Vlad Buslov <vladbu@mellanox.com> Cc: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net: sched: verify that q!=NULL before setting q->flagsVlad Buslov2019-07-281-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 503d81d428bd598430f7f9d02021634e1a8139a0 upstream. In function int tc_new_tfilter() q pointer can be NULL when adding filter on a shared block. With recent change that resets TCQ_F_CAN_BYPASS after filter creation, following NULL pointer dereference happens in case parent block is shared: [ 212.925060] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 212.925445] #PF: supervisor write access in kernel mode [ 212.925709] #PF: error_code(0x0002) - not-present page [ 212.925965] PGD 8000000827923067 P4D 8000000827923067 PUD 827924067 PMD 0 [ 212.926302] Oops: 0002 [#1] SMP KASAN PTI [ 212.926539] CPU: 18 PID: 2617 Comm: tc Tainted: G B 5.2.0+ #512 [ 212.926938] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 212.927364] RIP: 0010:tc_new_tfilter+0x698/0xd40 [ 212.927633] Code: 74 0d 48 85 c0 74 08 48 89 ef e8 03 aa 62 00 48 8b 84 24 a0 00 00 00 48 8d 78 10 48 89 44 24 18 e8 4d 0c 6b ff 48 8b 44 24 18 <83> 60 10 f b 48 85 ed 0f 85 3d fe ff ff e9 4f fe ff ff e8 81 26 f8 [ 212.928607] RSP: 0018:ffff88884fd5f5d8 EFLAGS: 00010296 [ 212.928905] RAX: 0000000000000000 RBX: 0000000000000000 RCX: dffffc0000000000 [ 212.929201] RDX: 0000000000000007 RSI: 0000000000000004 RDI: 0000000000000297 [ 212.929402] RBP: ffff88886bedd600 R08: ffffffffb91d4b51 R09: fffffbfff7616e4d [ 212.929609] R10: fffffbfff7616e4c R11: ffffffffbb0b7263 R12: ffff88886bc61040 [ 212.929803] R13: ffff88884fd5f950 R14: ffffc900039c5000 R15: ffff88835e927680 [ 212.929999] FS: 00007fe7c50b6480(0000) GS:ffff88886f980000(0000) knlGS:0000000000000000 [ 212.930235] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 212.930394] CR2: 0000000000000010 CR3: 000000085bd04002 CR4: 00000000001606e0 [ 212.930588] Call Trace: [ 212.930682] ? tc_del_tfilter+0xa40/0xa40 [ 212.930811] ? __lock_acquire+0x5b5/0x2460 [ 212.930948] ? find_held_lock+0x85/0xa0 [ 212.931081] ? tc_del_tfilter+0xa40/0xa40 [ 212.931201] rtnetlink_rcv_msg+0x4ab/0x5f0 [ 212.931332] ? rtnl_dellink+0x490/0x490 [ 212.931454] ? lockdep_hardirqs_on+0x260/0x260 [ 212.931589] ? netlink_deliver_tap+0xab/0x5a0 [ 212.931717] ? match_held_lock+0x1b/0x240 [ 212.931844] netlink_rcv_skb+0xd0/0x200 [ 212.931958] ? rtnl_dellink+0x490/0x490 [ 212.932079] ? netlink_ack+0x440/0x440 [ 212.932205] ? netlink_deliver_tap+0x161/0x5a0 [ 212.932335] ? lock_downgrade+0x360/0x360 [ 212.932457] ? lock_acquire+0xe5/0x210 [ 212.932579] netlink_unicast+0x296/0x350 [ 212.932705] ? netlink_attachskb+0x390/0x390 [ 212.932834] ? _copy_from_iter_full+0xe0/0x3a0 [ 212.932976] netlink_sendmsg+0x394/0x600 [ 212.937998] ? netlink_unicast+0x350/0x350 [ 212.943033] ? move_addr_to_kernel.part.0+0x90/0x90 [ 212.948115] ? netlink_unicast+0x350/0x350 [ 212.953185] sock_sendmsg+0x96/0xa0 [ 212.958099] ___sys_sendmsg+0x482/0x520 [ 212.962881] ? match_held_lock+0x1b/0x240 [ 212.967618] ? copy_msghdr_from_user+0x250/0x250 [ 212.972337] ? lock_downgrade+0x360/0x360 [ 212.976973] ? rwlock_bug.part.0+0x60/0x60 [ 212.981548] ? __mod_node_page_state+0x1f/0xa0 [ 212.986060] ? match_held_lock+0x1b/0x240 [ 212.990567] ? find_held_lock+0x85/0xa0 [ 212.994989] ? do_user_addr_fault+0x349/0x5b0 [ 212.999387] ? lock_downgrade+0x360/0x360 [ 213.003713] ? find_held_lock+0x85/0xa0 [ 213.007972] ? __fget_light+0xa1/0xf0 [ 213.012143] ? sockfd_lookup_light+0x91/0xb0 [ 213.016165] __sys_sendmsg+0xba/0x130 [ 213.020040] ? __sys_sendmsg_sock+0xb0/0xb0 [ 213.023870] ? handle_mm_fault+0x337/0x470 [ 213.027592] ? page_fault+0x8/0x30 [ 213.031316] ? lockdep_hardirqs_off+0xbe/0x100 [ 213.034999] ? mark_held_locks+0x24/0x90 [ 213.038671] ? do_syscall_64+0x1e/0xe0 [ 213.042297] do_syscall_64+0x74/0xe0 [ 213.045828] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 213.049354] RIP: 0033:0x7fe7c527c7b8 [ 213.052792] 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 f 0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 89 54 [ 213.060269] RSP: 002b:00007ffc3f7908a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 213.064144] RAX: ffffffffffffffda RBX: 000000005d34716f RCX: 00007fe7c527c7b8 [ 213.068094] RDX: 0000000000000000 RSI: 00007ffc3f790910 RDI: 0000000000000003 [ 213.072109] RBP: 0000000000000000 R08: 0000000000000001 R09: 00007fe7c5340cc0 [ 213.076113] R10: 0000000000404ec2 R11: 0000000000000246 R12: 0000000000000080 [ 213.080146] R13: 0000000000480640 R14: 0000000000000080 R15: 0000000000000000 [ 213.084147] Modules linked in: act_gact cls_flower sch_ingress nfsv3 nfs_acl nfs lockd grace fscache bridge stp llc sunrpc intel_rapl_msr intel_rapl_common [<1;69;32Msb_edac rdma_ucm rdma_cm x86_pkg_temp_thermal iw_cm intel_powerclamp ib_cm coretemp kvm_intel kvm irqbypass mlx5_ib ib_uverbs ib_core crct10dif_pclmul crc32_pc lmul crc32c_intel ghash_clmulni_intel mlx5_core intel_cstate intel_uncore iTCO_wdt igb iTCO_vendor_support mlxfw mei_me ptp ses intel_rapl_perf mei pcspkr ipmi _ssif i2c_i801 joydev enclosure pps_core lpc_ich ioatdma wmi dca ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter acpi_pad ast i2c_algo_bit drm_vram_helpe r ttm drm_kms_helper drm mpt3sas raid_class scsi_transport_sas [ 213.112326] CR2: 0000000000000010 [ 213.117429] ---[ end trace adb58eb0a4ee6283 ]--- Verify that q pointer is not NULL before setting the 'flags' field. Fixes: 3f05e6886a59 ("net_sched: unset TCQ_F_CAN_BYPASS when adding filters") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net_sched: unset TCQ_F_CAN_BYPASS when adding filtersCong Wang2019-07-281-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 3f05e6886a595c9a29a309c52f45326be917823c ] For qdisc's that support TC filters and set TCQ_F_CAN_BYPASS, notably fq_codel, it makes no sense to let packets bypass the TC filters we setup in any scenario, otherwise our packets steering policy could not be enforced. This can be reproduced easily with the following script: ip li add dev dummy0 type dummy ifconfig dummy0 up tc qd add dev dummy0 root fq_codel tc filter add dev dummy0 parent 8001: protocol arp basic action mirred egress redirect dev lo tc filter add dev dummy0 parent 8001: protocol ip basic action mirred egress redirect dev lo ping -I dummy0 192.168.112.1 Without this patch, packets are sent directly to dummy0 without hitting any of the filters. With this patch, packets are redirected to loopback as expected. This fix is not perfect, it only unsets the flag but does not set it back because we have to save the information somewhere in the qdisc if we really want that. Note, both fq_codel and sfq clear this flag in their ->bind_tcf() but this is clearly not sufficient when we don't use any class ID. Fixes: 23624935e0c4 ("net_sched: TCQ_F_CAN_BYPASS generalization") Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner2019-05-301-6/+1
| | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net/sched: add police action to the hardware intermediate representationPieter Jansen van Vuuren2019-05-051-0/+6
| | | | | | | | | | Add police action to the hardware intermediate representation which would subsequently allow it to be used by drivers for offload. Signed-off-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/sched: add sample action to the hardware intermediate representationPieter Jansen van Vuuren2019-05-051-0/+8
| | | | | | | | | | Add sample action to the hardware intermediate representation model which would subsequently allow it to be used by drivers for offload. Signed-off-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: make validation more configurable for future strictnessJohannes Berg2019-04-271-8/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: make nla_nest_start() add NLA_F_NESTED flagMichal Kubecek2019-04-271-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most netlink based interfaces (including recently added ones) are still not setting it in kernel generated messages. Without the flag, message parsers not aware of attribute semantics (e.g. wireshark dissector or libmnl's mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display the structure of their contents. Unfortunately we cannot just add the flag everywhere as there may be userspace applications which check nlattr::nla_type directly rather than through a helper masking out the flags. Therefore the patch renames nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start() as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually are rewritten to use nla_nest_start(). Except for changes in include/net/netlink.h, the patch was generated using this semantic patch: @@ expression E1, E2; @@ -nla_nest_start(E1, E2) +nla_nest_start_noflag(E1, E2) @@ expression E1, E2; @@ -nla_nest_start_noflag(E1, E2 | NLA_F_NESTED) +nla_nest_start(E1, E2) Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: don't set tunnel for decap actionVlad Buslov2019-04-021-1/+0
| | | | | | | | | | | | | | Action tunnel_key doesn't have a metadata/tunnel for release(decap) action. Drivers do not dereference entry->tunnel pointer for that action type, so this behavior doesn't result in a crash at the moment. However, this needs to be corrected as a preparation for updating hardware offloads API to not rely on rtnl lock, for which flow_action code will copy the tunnel data to temporary buffer to prevent concurrent action overwrite from invalidating/freeing it. Fixes: 3a7b68617de7 ("cls_api: add translator to flow_action representation") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/sched: let actions use RCU to access 'goto_chain'Davide Caratti2019-03-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | use RCU when accessing the action chain, to avoid use after free in the traffic path when 'goto chain' is replaced on existing TC actions (see script below). Since the control action is read in the traffic path without holding the action spinlock, we need to explicitly ensure that a->goto_chain is not NULL before dereferencing (i.e it's not sufficient to rely on the value of TC_ACT_GOTO_CHAIN bits). Not doing so caused NULL dereferences in tcf_action_goto_chain_exec() when the following script: # tc chain add dev dd0 chain 42 ingress protocol ip flower \ > ip_proto udp action pass index 4 # tc filter add dev dd0 ingress protocol ip flower \ > ip_proto udp action csum udp goto chain 42 index 66 # tc chain del dev dd0 chain 42 ingress (start UDP traffic towards dd0) # tc action replace action csum udp pass index 66 was run repeatedly for several hours. Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Suggested-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net_sched: return correct value for *notify* functionsZhike Wang2019-03-131-9/+23
| | | | | | | | | | | | | | | | | | | | It is confusing to directly use return value of netlink_send()/ netlink_unicast() as the return value of *notify*, as it may be not error at all. Example: in tc_del_tfilter(), after calling tfilter_del_notify(), it will goto errout if (err). However, the netlink_send()/netlink_unicast() will return positive value even for successful case. So it may not call tcf_chain_tp_remove() and so on to clean up the resource, as a result, resource is leaked. It may be easier to only check the return value of tfilter_del_nofiy(), but it is more clean to correct all related functions. Co-developed-by: Zengmo Gao <gaozengmo@jd.com> Signed-off-by: Zhike Wang <wangzhike@jd.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: fix potential use-after-free in __tcf_chain_put()Vlad Buslov2019-03-081-10/+7
| | | | | | | | | | | | | | | | | When used with unlocked classifier that have filters attached to actions with goto chain, __tcf_chain_put() for last non action reference can race with calls to same function from action cleanup code that releases last action reference. In this case action cleanup handler could free the chain if it executes after all references to chain were released, but before all concurrent users finished using it. Modify __tcf_chain_put() to only access tcf_chain fields when holding block->lock. Remove local variables that were used to cache some tcf_chain fields and are no longer needed because their values can now be obtained directly from chain under block->lock protection. Fixes: 726d061286ce ("net: sched: prevent insertion of new classifiers during chain flush") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: fix typo in walker_check_empty()Vlad Buslov2019-02-261-2/+2
| | | | | | | | | | | | Function walker_check_empty() incorrectly verifies that tp pointer is not NULL, instead of actual filter pointer. Fix conditional to check the right pointer. Adjust filter pointer naming accordingly to other cls API functions. Fixes: 6676d5e416ee ("net: sched: set dedicated tcf_walker flag when tp is empty") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Reported-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: don't release block->lock when dumping chainsVlad Buslov2019-02-251-9/+7
| | | | | | | | | | | | Function tc_dump_chain() obtains and releases block->lock on each iteration of its inner loop that dumps all chains on block. Outputting chain template info is fast operation so locking/unlocking mutex multiple times is an overhead when lock is highly contested. Modify tc_dump_chain() to only obtain block->lock once and dump all chains without releasing it. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: set dedicated tcf_walker flag when tp is emptyVlad Buslov2019-02-251-4/+9
| | | | | | | | | | | | | | | Using tcf_walker->stop flag to determine when tcf_walker->fn() was called at least once is unreliable. Some classifiers set 'stop' flag on error before calling walker callback, other classifiers used to call it with NULL filter pointer when empty. In order to prevent further regressions, extend tcf_walker structure with dedicated 'nonempty' flag. Set this flag in tcf_walker->fn() implementation that is used to check if classifier has filters configured. Fixes: 8b64678e0af8 ("net: sched: refactor tp insert/delete for concurrent execution") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net_sched: initialize net pointer inside tcf_exts_init()Cong Wang2019-02-221-1/+0
| | | | | | | | | | | | | | | | For tcindex filter, it is too late to initialize the net pointer in tcf_exts_validate(), as tcf_exts_get_net() requires a non-NULL net pointer. We can just move its initialization into tcf_exts_init(), which just requires an additional parameter. This makes the code in tcindex_alloc_perfect_hash() prettier. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: potential NULL dereference in tcf_block_find()Dan Carpenter2019-02-211-1/+3
| | | | | | | | | The error code isn't set on this path so it would result in returning ERR_PTR(0) and a NULL dereference in the caller. Fixes: 18d3eefb17cf ("net: sched: refactor tcf_block_find() into standalone functions") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: remove duplicated include from cls_api.cYueHaibing2019-02-131-1/+0
| | | | | | | Remove duplicated include. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: unlock rules update APIVlad Buslov2019-02-121-17/+114
| | | | | | | | | | | | | | | | Register netlink protocol handlers for message types RTM_NEWTFILTER, RTM_DELTFILTER, RTM_GETTFILTER as unlocked. Set rtnl_held variable that tracks rtnl mutex state to be false by default. Introduce tcf_proto_is_unlocked() helper that is used to check tcf_proto_ops->flag to determine if ops can be called without taking rtnl lock. Manually lookup Qdisc, class and block in rule update handlers. Verify that both Qdisc ops and proto ops are unlocked before using any of their callbacks, and obtain rtnl lock otherwise. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: refactor tcf_block_find() into standalone functionsVlad Buslov2019-02-121-92/+149
| | | | | | | | | | | | | | | | Refactor tcf_block_find() code into three standalone functions: - __tcf_qdisc_find() to lookup Qdisc and increment its reference counter. - __tcf_qdisc_cl_find() to lookup class. - __tcf_block_find() to lookup block and increment its reference counter. This change is necessary to allow netlink tc rule update handlers to call these functions directly in order to conditionally take rtnl lock according to Qdisc class ops flags before calling any of class ops functions. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: extend proto ops to support unlocked classifiersVlad Buslov2019-02-121-75/+93
| | | | | | | | | | | | | | | Add 'rtnl_held' flag to tcf proto change, delete, destroy, dump, walk functions to track rtnl lock status. Extend users of these function in cls API to propagate rtnl lock status to them. This allows classifiers to obtain rtnl lock when necessary and to pass rtnl lock status to extensions and driver offload callbacks. Add flags field to tcf proto ops. Add flag value to indicate that classifier doesn't require rtnl lock. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: extend proto ops with 'put' callbackVlad Buslov2019-02-121-1/+11
| | | | | | | | | | | | Add optional tp->ops->put() API to be implemented for filter reference counting. This new function is called by cls API to release filter reference for filters returned by tp->ops->change() or tp->ops->get() functions. Implement tfilter_put() helper to call tp->ops->put() only for classifiers that implement it. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: track rtnl lock status when validating extensionsVlad Buslov2019-02-121-4/+5
| | | | | | | | | | | | | | | | Actions API is already updated to not rely on rtnl lock for synchronization. However, it need to be provided with rtnl status when called from classifiers API in order to be able to correctly release the lock when loading kernel module. Extend extension validation function with 'rtnl_held' flag which is passed to actions API. Add new 'rtnl_held' parameter to tcf_exts_validate() in cls API. No classifier is currently updated to support unlocked execution, so pass hardcoded 'true' flag parameter value. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: prevent insertion of new classifiers during chain flushVlad Buslov2019-02-121-6/+29
| | | | | | | | | | | | | | Extend tcf_chain with 'flushing' flag. Use the flag to prevent insertion of new classifier instances when chain flushing is in progress in order to prevent resource leak when tcf_proto is created by unlocked users concurrently. Return EAGAIN error from tcf_chain_tp_insert_unique() to restart tc_new_tfilter() and lookup the chain/proto again. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: refactor tp insert/delete for concurrent executionVlad Buslov2019-02-121-25/+152
| | | | | | | | | | | | | | | | | | | Implement unique insertion function to atomically attach tcf_proto to chain after verifying that no other tcf proto with specified priority exists. Implement delete function that verifies that tp is actually empty before deleting it. Use these functions to refactor cls API to account for concurrent tp and rule update instead of relying on rtnl lock. Add new 'deleting' flag to tcf proto. Use it to restart search when iterating over tp's on chain to prevent accessing potentially inval tp->next pointer. Extend tcf proto with spinlock that is intended to be used to protect its data from concurrent modification instead of relying on rtnl mutex. Use it to protect 'deleting' flag. Add lockdep macros to validate that lock is held when accessing protected fields. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: traverse classifiers in chain with tcf_get_next_proto()Vlad Buslov2019-02-121-10/+60
| | | | | | | | | | | | | All users of chain->filters_chain rely on rtnl lock and assume that no new classifier instances are added when traversing the list. Use tcf_get_next_proto() to traverse filters list without relying on rtnl mutex. This function iterates over classifiers by taking reference to current iterator classifier only and doesn't assume external synchronization of filters list. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: introduce reference counting for tcf_protoVlad Buslov2019-02-121-10/+43
| | | | | | | | | | | | In order to remove dependency on rtnl lock and allow concurrent tcf_proto modification, extend tcf_proto with reference counter. Implement helper get/put functions for tcf proto and use them to modify cls API to always take reference to tcf_proto while using it. Only release reference to parent chain after releasing last reference to tp. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: protect filter_chain list with filter_chain_lock mutexVlad Buslov2019-02-121-32/+79
| | | | | | | | | | | | | | | | | | Extend tcf_chain with new filter_chain_lock mutex. Always lock the chain when accessing filter_chain list, instead of relying on rtnl lock. Dereference filter_chain with tcf_chain_dereference() lockdep macro to verify that all users of chain_list have the lock taken. Rearrange tp insert/remove code in tc_new_tfilter/tc_del_tfilter to execute all necessary code while holding chain lock in order to prevent invalidation of chain_info structure by potential concurrent change. This also serializes calls to tcf_chain0_head_change(), which allows head change callbacks to rely on filter_chain_lock for synchronization instead of rtnl mutex. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: protect chain template accesses with block lockVlad Buslov2019-02-121-16/+57
| | | | | | | | | | | | | | | | When cls API is called without protection of rtnl lock, parallel modification of chain is possible, which means that chain template can be changed concurrently in certain circumstances. For example, when chain is 'deleted' by new user-space chain API, the chain might continue to be used if it is referenced by actions, and can be 're-created' again by user. In such case same chain structure is reused and its template is changed. To protect from described scenario, cache chain template while holding block lock. Introduce standalone tc_chain_notify_delete() function that works with cached template values, instead of chains themselves. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: traverse chains in block with tcf_get_next_chain()Vlad Buslov2019-02-121-25/+71
| | | | | | | | | | | | | | | | All users of block->chain_list rely on rtnl lock and assume that no new chains are added when traversing the list. Use tcf_get_next_chain() to traverse chain list without relying on rtnl mutex. This function iterates over chains by taking reference to current iterator chain only and doesn't assume external synchronization of chain list. Don't take reference to all chains in block when flushing and use tcf_get_next_chain() to safely iterate over chain list instead. Remove tcf_block_put_all_chains() that is no longer used. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: protect block->chain0 with block->lockVlad Buslov2019-02-121-3/+14
| | | | | | | | | | | In order to remove dependency on rtnl lock, use block->lock to protect chain0 struct from concurrent modification. Rearrange code in chain0 callback add and del functions to only access chain0 when block->lock is held. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: refactor tc_ctl_chain() to use block->lockVlad Buslov2019-02-121-11/+25
| | | | | | | | | | | In order to remove dependency on rtnl lock, modify chain API to use block->lock to protect chain from concurrent modification. Rearrange tc_ctl_chain() code to call tcf_chain_hold() while holding block->lock to prevent concurrent chain removal. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: protect chain->explicitly_created with block->lockVlad Buslov2019-02-121-6/+13
| | | | | | | | | | | In order to remove dependency on rtnl lock, protect tcf_chain->explicitly_created flag with block->lock. Consolidate code that checks and resets 'explicitly_created' flag into __tcf_chain_put() to execute it atomically with rest of code that puts chain reference. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: protect block state with mutexVlad Buslov2019-02-121-13/+71
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* cls_api: add translator to flow_action representationPablo Neira Ayuso2019-02-061-0/+99
| | | | | | | | | | This patch implements a new function to translate from native TC action to the new flow_action representation. Moreover, this patch also updates cls_flower to use this new function. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* flow_offload: add flow action infrastructurePablo Neira Ayuso2019-02-061-0/+17
| | | | | | | | | | This new infrastructure defines the nic actions that you can perform from existing network drivers. This infrastructure allows us to avoid a direct dependency with the native software TC action representation. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net_sched: refetch skb protocol for each filterCong Wang2019-01-161-2/+1
| | | | | | | | | | | | | | | | | | | | | | | Martin reported a set of filters don't work after changing from reclassify to continue. Looking into the code, it looks like skb protocol is not always fetched for each iteration of the filters. But, as demonstrated by Martin, TC actions could modify skb->protocol, for example act_vlan, this means we have to refetch skb protocol in each iteration, rather than using the one we fetch in the beginning of the loop. This bug is _not_ introduced by commit 3b3ae880266d ("net: sched: consolidate tc_classify{,_compat}"), technically, if act_vlan is the only action that modifies skb protocol, then it is commit c7e2b9689ef8 ("sched: introduce vlan action") which introduced this bug. Reported-by: Martin Olsson <martin.olsson+netdev@sentorsecurity.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net_sched: fold tcf_block_cb_call() into tc_setup_cb_call()Cong Wang2018-12-141-26/+20
| | | | | | | | | | | | | | | After commit 69bd48404f25 ("net/sched: Remove egdev mechanism"), tc_setup_cb_call() is nearly identical to tcf_block_cb_call(), so we can just fold tcf_block_cb_call() into tc_setup_cb_call() and remove its unused parameter 'exts'. Fixes: 69bd48404f25 ("net/sched: Remove egdev mechanism") Cc: Oz Shlomo <ozsh@mellanox.com> Cc: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Oz Shlomo <ozsh@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/sched: Remove egdev mechanismOz Shlomo2018-12-101-46/+1
| | | | | | | | | | | | The egdev mechanism was replaced by the TC indirect block notifications platform. Signed-off-by: Oz Shlomo <ozsh@mellanox.com> Reviewed-by: Eli Britstein <elibr@mellanox.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Cc: John Hurley <john.hurley@netronome.com> Cc: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
* net: sched: register callbacks for indirect tc block bindsJohn Hurley2018-11-111-1/+255
| | | | | | | | | | | | | | | | | | | | | | | | | | | Currently drivers can register to receive TC block bind/unbind callbacks by implementing the setup_tc ndo in any of their given netdevs. However, drivers may also be interested in binds to higher level devices (e.g. tunnel drivers) to potentially offload filters applied to them. Introduce indirect block devs which allows drivers to register callbacks for block binds on other devices. The callback is triggered when the device is bound to a block, allowing the driver to register for rules applied to that block using already available functions. Freeing an indirect block callback will trigger an unbind event (if necessary) to direct the driver to remove any offloaded rules and unreg any block rule callbacks. It is the responsibility of the implementing driver to clean any registered indirect block callbacks before exiting, if the block it still active at such a time. Allow registering an indirect block dev callback for a device that is already bound to a block. In this case (if it is an ingress block), register and also trigger the callback meaning that any already installed rules can be replayed to the calling driver. Signed-off-by: John Hurley <john.hurley@netronome.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2018-10-191-5/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | net/sched/cls_api.c has overlapping changes to a call to nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL to the 5th argument, and another (from 'net-next') added cb->extack instead of NULL to the 6th argument. net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to code which moved (to mr_table_dump)) in 'net-next'. Thanks to David Ahern for the heads up. Signed-off-by: David S. Miller <davem@davemloft.net>
| * net/sched: cls_api: add missing validation of netlink attributesDavide Caratti2018-10-151-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Similarly to what has been done in 8b4c3cdd9dd8 ("net: sched: Add policy validation for tc attributes"), fix classifier code to add validation of TCA_CHAIN and TCA_KIND netlink attributes. tested with: # ./tdc.py -c filter v2: Let sch_api and cls_api share nla_policy they have in common, thanks to David Ahern. v3: Avoid EXPORT_SYMBOL(), as validation of those attributes is not done by TC modules, thanks to Cong Wang. While at it, restore the 'Delete / get qdisc' comment to its orginal position, just above tc_get_qdisc() function prototype. Fixes: 5bc1701881e39 ("net: sched: introduce multichain support for filters") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: Add extack to nlmsg_parseDavid Ahern2018-10-081-2/+4
| | | | | | | | | | | | | | | | | | | | Make sure extack is passed to nlmsg_parse where easy to do so. Most of these are dump handlers and leveraging the extack in the netlink_callback. Signed-off-by: David Ahern <dsahern@gmail.com> Acked-by: Christian Brauner <christian@brauner.io> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net_sched: fix a crash in tc_new_tfilter()Cong Wang2018-10-011-1/+3
| | | | | | | | | | | | | | | | | | | | | | When tcf_block_find() fails, it already rollbacks the qdisc refcnt, so its caller doesn't need to clean up this again. Avoid calling qdisc_put() again by resetting qdisc to NULL for callers. Reported-by: syzbot+37b8770e6d5a8220a039@syzkaller.appspotmail.com Fixes: e368fdb61d8e ("net: sched: use Qdisc rcu API instead of relying on rtnl lock") Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: sched: use reference counting for tcf blocks on rules updateVlad Buslov2018-09-251-17/+21
| | | | | | | | | | | | | | | | | | | | | | | | In order to remove dependency on rtnl lock on rules update path, always take reference to block while using it on rules update path. Change tcf_block_get() error handling to properly release block with reference counting, instead of just destroying it, in order to accommodate potential concurrent users. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: sched: implement tcf_block_refcnt_{get|put}()Vlad Buslov2018-09-251-24/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement get/put function for blocks that only take/release the reference and perform deallocation. These functions are intended to be used by unlocked rules update path to always hold reference to block while working with it. They use on new fine-grained locking mechanisms introduced in previous patches in this set, instead of relying on global protection provided by rtnl lock. Extract code that is common with tcf_block_detach_ext() into common function __tcf_block_put(). Extend tcf_block with rcu to allow safe deallocation when it is accessed concurrently. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: sched: protect block idr with spinlockVlad Buslov2018-09-251-2/+13
| | | | | | | | | | | | | | | | | | Protect block idr access with spinlock, instead of relying on rtnl lock. Take tn->idr_lock spinlock during block insertion and removal. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: sched: implement functions to put and flush all chainsVlad Buslov2018-09-251-25/+30
| | | | | | | | | | | | | | | | | | | | Extract code that flushes and puts all chains on tcf block to two standalone function to be shared with functions that locklessly get/put reference to block. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: sched: change tcf block reference counter type to refcount_tVlad Buslov2018-09-251-24/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As a preparation for removing rtnl lock dependency from rules update path, change tcf block reference counter type to refcount_t to allow modification by concurrent users. In block put function perform decrement and check reference counter once to accommodate concurrent modification by unlocked users. After this change tcf_chain_put at the end of block put function is called with block->refcnt==0 and will deallocate block after the last chain is released, so there is no need to manually deallocate block in this case. However, if block reference counter reached 0 and there are no chains to release, block must still be deallocated manually. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: sched: use Qdisc rcu API instead of relying on rtnl lockVlad Buslov2018-09-251-15/+64
|/ | | | | | | | | | | | | As a preparation from removing rtnl lock dependency from rules update path, use Qdisc rcu and reference counting capabilities instead of relying on rtnl lock while working with Qdiscs. Create new tcf_block_release() function, and use it to free resources taken by tcf_block_find(). Currently, this function only releases Qdisc and it is extended in next patches in this series. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>