linux.git/net, branch v5.4-rc1 Linux kernel source tree Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-09-29T00:47:33+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-09-29T00:47:33+00:00 02dc96ef6c25f990452c114c59d75c368a1f4c8f Pull networking fixes from David Miller: 1) Sanity check URB networking device parameters to avoid divide by zero, from Oliver Neukum. 2) Disable global multicast filter in NCSI, otherwise LLDP and IPV6 don't work properly. Longer term this needs a better fix tho. From Vijay Khemka. 3) Small fixes to selftests (use ping when ping6 is not present, etc.) from David Ahern. 4) Bring back rt_uses_gateway member of struct rtable, it's semantics were not well understood and trying to remove it broke things. From David Ahern. 5) Move usbnet snaity checking, ignore endpoints with invalid wMaxPacketSize. From Bjørn Mork. 6) Missing Kconfig deps for sja1105 driver, from Mao Wenan. 7) Various small fixes to the mlx5 DR steering code, from Alaa Hleihel, Alex Vesker, and Yevgeny Kliteynik 8) Missing CAP_NET_RAW checks in various places, from Ori Nimron. 9) Fix crash when removing sch_cbs entry while offloading is enabled, from Vinicius Costa Gomes. 10) Signedness bug fixes, generally in looking at the result given by of_get_phy_mode() and friends. From Dan Crapenter. 11) Disable preemption around BPF_PROG_RUN() calls, from Eric Dumazet. 12) Don't create VRF ipv6 rules if ipv6 is disabled, from David Ahern. 13) Fix quantization code in tcp_bbr, from Kevin Yang. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (127 commits) net: tap: clean up an indentation issue nfp: abm: fix memory leak in nfp_abm_u32_knode_replace tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state sk_buff: drop all skb extensions on free and skb scrubbing tcp_bbr: fix quantization code to not raise cwnd if not probing bandwidth mlxsw: spectrum_flower: Fail in case user specifies multiple mirror actions Documentation: Clarify trap's description mlxsw: spectrum: Clear VLAN filters during port initialization net: ena: clean up indentation issue NFC: st95hf: clean up indentation issue net: phy: micrel: add Asym Pause workaround for KSZ9021 net: socionext: ave: Avoid using netdev_err() before calling register_netdev() ptp: correctly disable flags on old ioctls lib: dimlib: fix help text typos net: dsa: microchip: Always set regmap stride to 1 nfp: flower: fix memory leak in nfp_flower_spawn_vnic_reprs nfp: flower: prevent memory leak in nfp_flower_spawn_phy_reprs net/sched: Set default of CONFIG_NET_TC_SKB_EXT to N vrf: Do not attempt to create IPv6 mcast rule if IPv6 is disabled net: sched: sch_sfb: don't call qdisc_put() while holding tree lock ... 
Pull networking fixes from David Miller:

 1) Sanity check URB networking device parameters to avoid divide by
    zero, from Oliver Neukum.

 2) Disable global multicast filter in NCSI, otherwise LLDP and IPV6
    don't work properly. Longer term this needs a better fix tho. From
    Vijay Khemka.

 3) Small fixes to selftests (use ping when ping6 is not present, etc.)
    from David Ahern.

 4) Bring back rt_uses_gateway member of struct rtable, it's semantics
    were not well understood and trying to remove it broke things. From
    David Ahern.

 5) Move usbnet snaity checking, ignore endpoints with invalid
    wMaxPacketSize. From Bjørn Mork.

 6) Missing Kconfig deps for sja1105 driver, from Mao Wenan.

 7) Various small fixes to the mlx5 DR steering code, from Alaa Hleihel,
    Alex Vesker, and Yevgeny Kliteynik

 8) Missing CAP_NET_RAW checks in various places, from Ori Nimron.

 9) Fix crash when removing sch_cbs entry while offloading is enabled,
    from Vinicius Costa Gomes.

10) Signedness bug fixes, generally in looking at the result given by
    of_get_phy_mode() and friends. From Dan Crapenter.

11) Disable preemption around BPF_PROG_RUN() calls, from Eric Dumazet.

12) Don't create VRF ipv6 rules if ipv6 is disabled, from David Ahern.

13) Fix quantization code in tcp_bbr, from Kevin Yang.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (127 commits)
  net: tap: clean up an indentation issue
  nfp: abm: fix memory leak in nfp_abm_u32_knode_replace
  tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state
  sk_buff: drop all skb extensions on free and skb scrubbing
  tcp_bbr: fix quantization code to not raise cwnd if not probing bandwidth
  mlxsw: spectrum_flower: Fail in case user specifies multiple mirror actions
  Documentation: Clarify trap's description
  mlxsw: spectrum: Clear VLAN filters during port initialization
  net: ena: clean up indentation issue
  NFC: st95hf: clean up indentation issue
  net: phy: micrel: add Asym Pause workaround for KSZ9021
  net: socionext: ave: Avoid using netdev_err() before calling register_netdev()
  ptp: correctly disable flags on old ioctls
  lib: dimlib: fix help text typos
  net: dsa: microchip: Always set regmap stride to 1
  nfp: flower: fix memory leak in nfp_flower_spawn_vnic_reprs
  nfp: flower: prevent memory leak in nfp_flower_spawn_phy_reprs
  net/sched: Set default of CONFIG_NET_TC_SKB_EXT to N
  vrf: Do not attempt to create IPv6 mcast rule if IPv6 is disabled
  net: sched: sch_sfb: don't call qdisc_put() while holding tree lock
  ...
Merge tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux 2019-09-28T00:00:27+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-09-28T00:00:27+00:00 298fb76a5583900a155d387efaf37a8b39e5dea2 Pull nfsd updates from Bruce Fields: "Highlights: - Add a new knfsd file cache, so that we don't have to open and close on each (NFSv2/v3) READ or WRITE. This can speed up read and write in some cases. It also replaces our readahead cache. - Prevent silent data loss on write errors, by treating write errors like server reboots for the purposes of write caching, thus forcing clients to resend their writes. - Tweak the code that allocates sessions to be more forgiving, so that NFSv4.1 mounts are less likely to hang when a server already has a lot of clients. - Eliminate an arbitrary limit on NFSv4 ACL sizes; they should now be limited only by the backend filesystem and the maximum RPC size. - Allow the server to enforce use of the correct kerberos credentials when a client reclaims state after a reboot. And some miscellaneous smaller bugfixes and cleanup" * tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux: (34 commits) sunrpc: clean up indentation issue nfsd: fix nfs read eof detection nfsd: Make nfsd_reset_boot_verifier_locked static nfsd: degraded slot-count more gracefully as allocation nears exhaustion. nfsd: handle drc over-allocation gracefully. nfsd: add support for upcall version 2 nfsd: add a "GetVersion" upcall for nfsdcld nfsd: Reset the boot verifier on all write I/O errors nfsd: Don't garbage collect files that might contain write errors nfsd: Support the server resetting the boot verifier nfsd: nfsd_file cache entries should be per net namespace nfsd: eliminate an unnecessary acl size limit Deprecate nfsd fault injection nfsd: remove duplicated include from filecache.c nfsd: Fix the documentation for svcxdr_tmpalloc() nfsd: Fix up some unused variable warnings nfsd: close cached files prior to a REMOVE or RENAME that would replace target nfsd: rip out the raparms cache nfsd: have nfsd_test_lock use the nfsd_file cache nfsd: hook up nfs4_preprocess_stateid_op to the nfsd_file cache ... 
Pull nfsd updates from Bruce Fields:
 "Highlights:

   - Add a new knfsd file cache, so that we don't have to open and close
     on each (NFSv2/v3) READ or WRITE. This can speed up read and write
     in some cases. It also replaces our readahead cache.

   - Prevent silent data loss on write errors, by treating write errors
     like server reboots for the purposes of write caching, thus forcing
     clients to resend their writes.

   - Tweak the code that allocates sessions to be more forgiving, so
     that NFSv4.1 mounts are less likely to hang when a server already
     has a lot of clients.

   - Eliminate an arbitrary limit on NFSv4 ACL sizes; they should now be
     limited only by the backend filesystem and the maximum RPC size.

   - Allow the server to enforce use of the correct kerberos credentials
     when a client reclaims state after a reboot.

  And some miscellaneous smaller bugfixes and cleanup"

* tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux: (34 commits)
  sunrpc: clean up indentation issue
  nfsd: fix nfs read eof detection
  nfsd: Make nfsd_reset_boot_verifier_locked static
  nfsd: degraded slot-count more gracefully as allocation nears exhaustion.
  nfsd: handle drc over-allocation gracefully.
  nfsd: add support for upcall version 2
  nfsd: add a "GetVersion" upcall for nfsdcld
  nfsd: Reset the boot verifier on all write I/O errors
  nfsd: Don't garbage collect files that might contain write errors
  nfsd: Support the server resetting the boot verifier
  nfsd: nfsd_file cache entries should be per net namespace
  nfsd: eliminate an unnecessary acl size limit
  Deprecate nfsd fault injection
  nfsd: remove duplicated include from filecache.c
  nfsd: Fix the documentation for svcxdr_tmpalloc()
  nfsd: Fix up some unused variable warnings
  nfsd: close cached files prior to a REMOVE or RENAME that would replace target
  nfsd: rip out the raparms cache
  nfsd: have nfsd_test_lock use the nfsd_file cache
  nfsd: hook up nfs4_preprocess_stateid_op to the nfsd_file cache
  ...
Merge tag '9p-for-5.4' of git://github.com/martinetd/linux 2019-09-27T22:10:34+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-09-27T22:10:34+00:00 9977b1a71488742606376c09e19e0074e4403cdf Pull 9p updates from Dominique Martinet: "Some of the usual small fixes and cleanup. Small fixes all around: - avoid overlayfs copy-up for PRIVATE mmaps - KUMSAN uninitialized warning for transport error - one syzbot memory leak fix in 9p cache - internal API cleanup for v9fs_fill_super" * tag '9p-for-5.4' of git://github.com/martinetd/linux: 9p/vfs_super.c: Remove unused parameter data in v9fs_fill_super 9p/cache.c: Fix memory leak in v9fs_cache_session_get_cookie 9p: Transport error uninitialized 9p: avoid attaching writeback_fid on mmap with type PRIVATE 
Pull 9p updates from Dominique Martinet:
 "Some of the usual small fixes and cleanup.

  Small fixes all around:
   - avoid overlayfs copy-up for PRIVATE mmaps
   - KUMSAN uninitialized warning for transport error
   - one syzbot memory leak fix in 9p cache
   - internal API cleanup for v9fs_fill_super"

* tag '9p-for-5.4' of git://github.com/martinetd/linux:
  9p/vfs_super.c: Remove unused parameter data in v9fs_fill_super
  9p/cache.c: Fix memory leak in v9fs_cache_session_get_cookie
  9p: Transport error uninitialized
  9p: avoid attaching writeback_fid on mmap with type PRIVATE
tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state 2019-09-27T18:42:24+00:00 Eric Dumazet edumazet@google.com 2019-09-26T22:42:51+00:00 a41e8a88b06ee39fad4cb4a8ccf822563560a89c Yuchung Cheng and Marek Majkowski independently reported a weird behavior of TCP_USER_TIMEOUT option when used at connect() time. When the TCP_USER_TIMEOUT is reached, tcp_write_timeout() believes the flow should live, and the following condition in tcp_clamp_rto_to_user_timeout() programs one jiffie timers : remaining = icsk->icsk_user_timeout - elapsed; if (remaining <= 0) return 1; /* user timeout has passed; fire ASAP */ This silly situation ends when the max syn rtx count is reached. This patch makes sure we honor both TCP_SYNCNT and TCP_USER_TIMEOUT, avoiding these spurious SYN packets. Fixes: b701a99e431d ("tcp: Add tcp_clamp_rto_to_user_timeout() helper to improve accuracy") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Yuchung Cheng <ycheng@google.com> Reported-by: Marek Majkowski <marek@cloudflare.com> Cc: Jon Maxwell <jmaxwell37@gmail.com> Link: https://marc.info/?l=linux-netdev&m=156940118307949&w=2 Acked-by: Jon Maxwell <jmaxwell37@gmail.com> Tested-by: Marek Majkowski <marek@cloudflare.com> Signed-off-by: Marek Majkowski <marek@cloudflare.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Yuchung Cheng and Marek Majkowski independently reported a weird
behavior of TCP_USER_TIMEOUT option when used at connect() time.

When the TCP_USER_TIMEOUT is reached, tcp_write_timeout()
believes the flow should live, and the following condition
in tcp_clamp_rto_to_user_timeout() programs one jiffie timers :

    remaining = icsk->icsk_user_timeout - elapsed;
    if (remaining <= 0)
        return 1; /* user timeout has passed; fire ASAP */

This silly situation ends when the max syn rtx count is reached.

This patch makes sure we honor both TCP_SYNCNT and TCP_USER_TIMEOUT,
avoiding these spurious SYN packets.

Fixes: b701a99e431d ("tcp: Add tcp_clamp_rto_to_user_timeout() helper to improve accuracy")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Yuchung Cheng <ycheng@google.com>
Reported-by: Marek Majkowski <marek@cloudflare.com>
Cc: Jon Maxwell <jmaxwell37@gmail.com>
Link: https://marc.info/?l=linux-netdev&m=156940118307949&w=2
Acked-by: Jon Maxwell <jmaxwell37@gmail.com>
Tested-by: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: Marek Majkowski <marek@cloudflare.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk_buff: drop all skb extensions on free and skb scrubbing 2019-09-27T18:40:19+00:00 Florian Westphal fw@strlen.de 2019-09-26T18:37:05+00:00 174e23810cd3183dc2ca3f5166ef965a55eaaf54 Now that we have a 3rd extension, add a new helper that drops the extension space and use it when we need to scrub an sk_buff. At this time, scrubbing clears secpath and bridge netfilter data, but retains the tc skb extension, after this patch all three get cleared. NAPI reuse/free assumes we can only have a secpath attached to skb, but it seems better to clear all extensions there as well. v2: add unlikely hint (Eric Dumazet) Fixes: 95a7233c452a ("net: openvswitch: Set OvS recirc_id from tc chain index") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net> 
Now that we have a 3rd extension, add a new helper that drops the
extension space and use it when we need to scrub an sk_buff.

At this time, scrubbing clears secpath and bridge netfilter data, but
retains the tc skb extension, after this patch all three get cleared.

NAPI reuse/free assumes we can only have a secpath attached to skb, but
it seems better to clear all extensions there as well.

v2: add unlikely hint (Eric Dumazet)

Fixes: 95a7233c452a ("net: openvswitch: Set OvS recirc_id from tc chain index")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp_bbr: fix quantization code to not raise cwnd if not probing bandwidth 2019-09-27T18:37:50+00:00 Kevin(Yudong) Yang yyd@google.com 2019-09-26T14:30:05+00:00 6b3656a60f2067738d1a423328199720806f0c44 There was a bug in the previous logic that attempted to ensure gain cycling gets inflight above BDP even for small BDPs. This code correctly raised and lowered target inflight values during the gain cycle. And this code correctly ensured that cwnd was raised when probing bandwidth. However, it did not correspondingly ensure that cwnd was *not* raised in this way when *not* probing for bandwidth. The result was that small-BDP flows that were always cwnd-bound could go for many cycles with a fixed cwnd, and not probe or yield bandwidth at all. This meant that multiple small-BDP flows could fail to converge in their bandwidth allocations. Fixes: 3c346b233c68 ("tcp_bbr: fix bw probing to raise in-flight data for very small BDPs") Signed-off-by: Kevin(Yudong) Yang <yyd@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Priyaranjan Jha <priyarjha@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
There was a bug in the previous logic that attempted to ensure gain cycling
gets inflight above BDP even for small BDPs. This code correctly raised and
lowered target inflight values during the gain cycle. And this code
correctly ensured that cwnd was raised when probing bandwidth. However, it
did not correspondingly ensure that cwnd was *not* raised in this way when
*not* probing for bandwidth. The result was that small-BDP flows that were
always cwnd-bound could go for many cycles with a fixed cwnd, and not probe
or yield bandwidth at all. This meant that multiple small-BDP flows could
fail to converge in their bandwidth allocations.

Fixes: 3c346b233c68 ("tcp_bbr: fix bw probing to raise in-flight data for very small BDPs")
Signed-off-by: Kevin(Yudong) Yang <yyd@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Priyaranjan Jha <priyarjha@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2019-09-27T18:15:00+00:00 David S. Miller davem@davemloft.net 2019-09-27T18:15:00+00:00 c5f095baa880036702595a09de38e7a0ca420c0b Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: 1) Add NFT_CHAIN_POLICY_UNSET to replace hardcoded -1 to specify that the chain policy is unset. The chain policy field is actually defined as an 8-bit unsigned integer. 2) Remove always true condition reported by smatch in chain policy check. 3) Fix element lookup on dynamic sets, from Florian Westphal. 4) Use __u8 in ebtables uapi header, from Masahiro Yamada. 5) Bogus EBUSY when removing flowtable after chain flush, from Laura Garcia Liebana. ==================== Signed-off-by: David S. Miller <davem@davemloft.net> 
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Add NFT_CHAIN_POLICY_UNSET to replace hardcoded -1 to
   specify that the chain policy is unset. The chain policy
   field is actually defined as an 8-bit unsigned integer.

2) Remove always true condition reported by smatch in
   chain policy check.

3) Fix element lookup on dynamic sets, from Florian Westphal.

4) Use __u8 in ebtables uapi header, from Masahiro Yamada.

5) Bogus EBUSY when removing flowtable after chain flush,
   from Laura Garcia Liebana.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
net/sched: Set default of CONFIG_NET_TC_SKB_EXT to N 2019-09-27T18:08:28+00:00 Paul Blakey paulb@mellanox.com 2019-09-25T15:02:35+00:00 dfe5999dc03e321d08190772c98843284d5cf419 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> 
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>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2019-09-27T14:23:32+00:00 David S. Miller davem@davemloft.net 2019-09-27T14:23:32+00:00 3c30819dc68ab9498216421b6846123900c0a6d3 Daniel Borkmann says: ==================== pull-request: bpf 2019-09-27 The following pull-request contains BPF updates for your *net* tree. The main changes are: 1) Fix libbpf's BTF dumper to not skip anonymous enum definitions, from Andrii. 2) Fix BTF verifier issues when handling the BTF of vmlinux, from Alexei. 3) Fix nested calls into bpf_event_output() from TCP sockops BPF programs, from Allan. 4) Fix NULL pointer dereference in AF_XDP's xsk map creation when allocation fails, from Jonathan. 5) Remove unneeded 64 byte alignment requirement of the AF_XDP UMEM headroom, from Bjorn. 6) Remove unused XDP_OPTIONS getsockopt() call which results in an error on older kernels, from Toke. 7) Fix a client/server race in tcp_rtt BPF kselftest case, from Stanislav. 8) Fix indentation issue in BTF's btf_enum_check_kflag_member(), from Colin. ==================== Signed-off-by: David S. Miller <davem@davemloft.net> 
Daniel Borkmann says:

====================
pull-request: bpf 2019-09-27

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix libbpf's BTF dumper to not skip anonymous enum definitions, from Andrii.

2) Fix BTF verifier issues when handling the BTF of vmlinux, from Alexei.

3) Fix nested calls into bpf_event_output() from TCP sockops BPF
   programs, from Allan.

4) Fix NULL pointer dereference in AF_XDP's xsk map creation when
   allocation fails, from Jonathan.

5) Remove unneeded 64 byte alignment requirement of the AF_XDP UMEM
   headroom, from Bjorn.

6) Remove unused XDP_OPTIONS getsockopt() call which results in an error
   on older kernels, from Toke.

7) Fix a client/server race in tcp_rtt BPF kselftest case, from Stanislav.

8) Fix indentation issue in BTF's btf_enum_check_kflag_member(), from Colin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
net: sched: sch_sfb: don't call qdisc_put() while holding tree lock 2019-09-27T10:13:55+00:00 Vlad Buslov vladbu@mellanox.com 2019-09-24T15:51:18+00:00 e3ae1f96accd21405715fe9c56b4d83bc7d96d44 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> 
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>