Commit Graph

7 Commits

Author SHA1 Message Date
Linus Lüssing e9950a749a mac80211: mesh: fix discovery timer re-arming issue / crash
commit e2d4a80f93fcfaf72e2e20daf6a28e39c3b90677 upstream.

On a non-forwarding 802.11s link between two fairly busy
neighboring nodes (iperf with -P 16 at ~850MBit/s TCP;
1733.3 MBit/s VHT-MCS 9 80MHz short GI VHT-NSS 4), so with
frequent PREQ retries, usually after around 30-40 seconds the
following crash would occur:

[ 1110.822428] Unable to handle kernel read from unreadable memory at virtual address 00000000
[ 1110.830786] Mem abort info:
[ 1110.833573]   Exception class = IABT (current EL), IL = 32 bits
[ 1110.839494]   SET = 0, FnV = 0
[ 1110.842546]   EA = 0, S1PTW = 0
[ 1110.845678] user pgtable: 4k pages, 48-bit VAs, pgd = ffff800076386000
[ 1110.852204] [0000000000000000] *pgd=00000000f6322003, *pud=00000000f62de003, *pmd=0000000000000000
[ 1110.861167] Internal error: Oops: 86000004 [#1] PREEMPT SMP
[ 1110.866730] Modules linked in: pppoe ppp_async batman_adv ath10k_pci ath10k_core ath pppox ppp_generic nf_conntrack_ipv6 mac80211 iptable_nat ipt_REJECT ipt_MASQUERADE cfg80211 xt_time xt_tcpudp xt_state xt_nat xt_multiport xt_mark xt_mac xt_limit xt_conntrack xt_comment xt_TCPMSS xt_REDIRECT xt_LOG xt_FLOWOFFLOAD slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_flow_table_hw nf_flow_table nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 usb_storage xhci_plat_hcd xhci_pci xhci_hcd dwc3 usbcore usb_common
[ 1110.932190] Process swapper/3 (pid: 0, stack limit = 0xffff0000090c8000)
[ 1110.938884] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.14.162 #0
[ 1110.944965] Hardware name: LS1043A RGW Board (DT)
[ 1110.949658] task: ffff8000787a81c0 task.stack: ffff0000090c8000
[ 1110.955568] PC is at 0x0
[ 1110.958097] LR is at call_timer_fn.isra.27+0x24/0x78
[ 1110.963055] pc : [<0000000000000000>] lr : [<ffff0000080ff29c>] pstate: 00400145
[ 1110.970440] sp : ffff00000801be10
[ 1110.973744] x29: ffff00000801be10 x28: ffff000008bf7018
[ 1110.979047] x27: ffff000008bf87c8 x26: ffff000008c160c0
[ 1110.984352] x25: 0000000000000000 x24: 0000000000000000
[ 1110.989657] x23: dead000000000200 x22: 0000000000000000
[ 1110.994959] x21: 0000000000000000 x20: 0000000000000101
[ 1111.000262] x19: ffff8000787a81c0 x18: 0000000000000000
[ 1111.005565] x17: ffff0000089167b0 x16: 0000000000000058
[ 1111.010868] x15: ffff0000089167b0 x14: 0000000000000000
[ 1111.016172] x13: ffff000008916788 x12: 0000000000000040
[ 1111.021475] x11: ffff80007fda9af0 x10: 0000000000000001
[ 1111.026777] x9 : ffff00000801bea0 x8 : 0000000000000004
[ 1111.032080] x7 : 0000000000000000 x6 : ffff80007fda9aa8
[ 1111.037383] x5 : ffff00000801bea0 x4 : 0000000000000010
[ 1111.042685] x3 : ffff00000801be98 x2 : 0000000000000614
[ 1111.047988] x1 : 0000000000000000 x0 : 0000000000000000
[ 1111.053290] Call trace:
[ 1111.055728] Exception stack(0xffff00000801bcd0 to 0xffff00000801be10)
[ 1111.062158] bcc0:                                   0000000000000000 0000000000000000
[ 1111.069978] bce0: 0000000000000614 ffff00000801be98 0000000000000010 ffff00000801bea0
[ 1111.077798] bd00: ffff80007fda9aa8 0000000000000000 0000000000000004 ffff00000801bea0
[ 1111.085618] bd20: 0000000000000001 ffff80007fda9af0 0000000000000040 ffff000008916788
[ 1111.093437] bd40: 0000000000000000 ffff0000089167b0 0000000000000058 ffff0000089167b0
[ 1111.101256] bd60: 0000000000000000 ffff8000787a81c0 0000000000000101 0000000000000000
[ 1111.109075] bd80: 0000000000000000 dead000000000200 0000000000000000 0000000000000000
[ 1111.116895] bda0: ffff000008c160c0 ffff000008bf87c8 ffff000008bf7018 ffff00000801be10
[ 1111.124715] bdc0: ffff0000080ff29c ffff00000801be10 0000000000000000 0000000000400145
[ 1111.132534] bde0: ffff8000787a81c0 ffff00000801bde8 0000ffffffffffff 000001029eb19be8
[ 1111.140353] be00: ffff00000801be10 0000000000000000
[ 1111.145220] [<          (null)>]           (null)
[ 1111.149917] [<ffff0000080ff77c>] run_timer_softirq+0x184/0x398
[ 1111.155741] [<ffff000008081938>] __do_softirq+0x100/0x1fc
[ 1111.161130] [<ffff0000080a2e28>] irq_exit+0x80/0xd8
[ 1111.166002] [<ffff0000080ea708>] __handle_domain_irq+0x88/0xb0
[ 1111.171825] [<ffff000008081678>] gic_handle_irq+0x68/0xb0
[ 1111.177213] Exception stack(0xffff0000090cbe30 to 0xffff0000090cbf70)
[ 1111.183642] be20:                                   0000000000000020 0000000000000000
[ 1111.191461] be40: 0000000000000001 0000000000000000 00008000771af000 0000000000000000
[ 1111.199281] be60: ffff000008c95180 0000000000000000 ffff000008c19360 ffff0000090cbef0
[ 1111.207101] be80: 0000000000000810 0000000000000400 0000000000000098 ffff000000000000
[ 1111.214920] bea0: 0000000000000001 ffff0000089167b0 0000000000000000 ffff0000089167b0
[ 1111.222740] bec0: 0000000000000000 ffff000008c198e8 ffff000008bf7018 ffff000008c19000
[ 1111.230559] bee0: 0000000000000000 0000000000000000 ffff8000787a81c0 ffff000008018000
[ 1111.238380] bf00: ffff00000801c000 ffff00000913ba34 ffff8000787a81c0 ffff0000090cbf70
[ 1111.246199] bf20: ffff0000080857cc ffff0000090cbf70 ffff0000080857d0 0000000000400145
[ 1111.254020] bf40: ffff000008018000 ffff00000801c000 ffffffffffffffff ffff0000080fa574
[ 1111.261838] bf60: ffff0000090cbf70 ffff0000080857d0
[ 1111.266706] [<ffff0000080832e8>] el1_irq+0xe8/0x18c
[ 1111.271576] [<ffff0000080857d0>] arch_cpu_idle+0x10/0x18
[ 1111.276880] [<ffff0000080d7de4>] do_idle+0xec/0x1b8
[ 1111.281748] [<ffff0000080d8020>] cpu_startup_entry+0x20/0x28
[ 1111.287399] [<ffff00000808f81c>] secondary_start_kernel+0x104/0x110
[ 1111.293662] Code: bad PC value
[ 1111.296710] ---[ end trace 555b6ca4363c3edd ]---
[ 1111.301318] Kernel panic - not syncing: Fatal exception in interrupt
[ 1111.307661] SMP: stopping secondary CPUs
[ 1111.311574] Kernel Offset: disabled
[ 1111.315053] CPU features: 0x0002000
[ 1111.318530] Memory Limit: none
[ 1111.321575] Rebooting in 3 seconds..

With some added debug output / delays we were able to push the crash from
the timer callback runner into the callback function and by that shedding
some light on which object holding the timer gets corrupted:

[  401.720899] Unable to handle kernel read from unreadable memory at virtual address 00000868
[...]
[  402.335836] [<ffff0000088fafa4>] _raw_spin_lock_bh+0x14/0x48
[  402.341548] [<ffff000000dbe684>] mesh_path_timer+0x10c/0x248 [mac80211]
[  402.348154] [<ffff0000080ff29c>] call_timer_fn.isra.27+0x24/0x78
[  402.354150] [<ffff0000080ff77c>] run_timer_softirq+0x184/0x398
[  402.359974] [<ffff000008081938>] __do_softirq+0x100/0x1fc
[  402.365362] [<ffff0000080a2e28>] irq_exit+0x80/0xd8
[  402.370231] [<ffff0000080ea708>] __handle_domain_irq+0x88/0xb0
[  402.376053] [<ffff000008081678>] gic_handle_irq+0x68/0xb0

The issue happens due to the following sequence of events:

1) mesh_path_start_discovery():
-> spin_unlock_bh(&mpath->state_lock) before mesh_path_sel_frame_tx()

2) mesh_path_free_rcu()
-> del_timer_sync(&mpath->timer)
   [...]
-> kfree_rcu(mpath)

3) mesh_path_start_discovery():
-> mod_timer(&mpath->timer, ...)
   [...]
-> rcu_read_unlock()

4) mesh_path_free_rcu()'s kfree_rcu():
-> kfree(mpath)

5) mesh_path_timer() starts after timeout, using freed mpath object

So a use-after-free issue due to a timer re-arming bug caused by an
early spin-unlocking.

This patch fixes this issue by re-checking if mpath is about to be
free'd and if so bails out of re-arming the timer.

Cc: stable@vger.kernel.org
Fixes: 050ac52cbe1f ("mac80211: code for on-demand Hybrid Wireless Mesh Protocol")
Cc: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Linus Lüssing <ll@simonwunderlich.de>
Link: https://lore.kernel.org/r/20200522170413.14973-1-linus.luessing@c0d3.blue
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:28:38 +08:00
Thomas Pedersen d19ad942c0 mac80211: add ieee80211_is_any_nullfunc()
commit 30b2f0be23fb40e58d0ad2caf8702c2a44cda2e1 upstream.

commit 08a5bdde3812 ("mac80211: consider QoS Null frames for STA_NULLFUNC_ACKED")
Fixed a bug where we failed to take into account a
nullfunc frame can be either non-QoS or QoS. It turns out
there is at least one more bug in
ieee80211_sta_tx_notify(), introduced in
commit 7b6ddeaf27ec ("mac80211: use QoS NDP for AP probing"),
where we forgot to check for the QoS variant and so
assumed the QoS nullfunc frame never went out

Fix this by adding a helper ieee80211_is_any_nullfunc()
which consolidates the check for non-QoS and QoS nullfunc
frames. Replace existing compound conditionals and add a
couple more missing checks for QoS variant.

Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200114055940.18502-3-thomas@adapt-ip.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:27:30 +08:00
Madhuparna Bhowmik c66c2b0220 mac80211: sta_info: Add lockdep condition for RCU list usage
[ Upstream commit 8ca47eb9f9e4e10e7e7fa695731a88941732c38d ]

The function sta_info_get_by_idx() uses RCU list primitive.
It is called with  local->sta_mtx held from mac80211/cfg.c.
Add lockdep expression to avoid any false positive RCU list warnings.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Link: https://lore.kernel.org/r/20200409082906.27427-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:27:28 +08:00
Tamizh chelvam e571752038 mac80211: fix channel switch trigger from unknown mesh peer
[ Upstream commit 93e2d04a1888668183f3fb48666e90b9b31d29e6 ]

Previously mesh channel switch happens if beacon contains
CSA IE without checking the mesh peer info. Due to that
channel switch happens even if the beacon is not from
its own mesh peer. Fixing that by checking if the CSA
originated from the same mesh network before proceeding
for channel switch.

Signed-off-by: Tamizh chelvam <tamizhr@codeaurora.org>
Link: https://lore.kernel.org/r/1585403604-29274-1-git-send-email-tamizhr@codeaurora.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:27:14 +08:00
Johannes Berg 0abbbbb6d3 mac80211: populate debugfs only after cfg80211 init
commit 6cb5f3ea4654faf8c28b901266e960b1a4787b26 upstream.

When fixing the initialization race, we neglected to account for
the fact that debugfs is initialized in wiphy_register(), and
some debugfs things went missing (or rather were rerooted to the
global debugfs root).

Fix this by adding debugfs entries only after wiphy_register().
This requires some changes in the rate control code since it
currently adds debugfs at alloc time, which can no longer be
done after the reordering.

Reported-by: Jouni Malinen <j@w1.fi>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Reported-by: Hauke Mehrtens <hauke@hauke-m.de>
Reported-by: Felix Fietkau <nbd@nbd.name>
Cc: stable@vger.kernel.org
Fixes: 52e04b4ce5d0 ("mac80211: fix race in ieee80211_register_hw()")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/20200423111344.0e00d3346f12.Iadc76a03a55093d94391fc672e996a458702875d@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:26:59 +08:00
Sumit Garg 1def0296de mac80211: fix race in ieee80211_register_hw()
commit 52e04b4ce5d03775b6a78f3ed1097480faacc9fd upstream.

A race condition leading to a kernel crash is observed during invocation
of ieee80211_register_hw() on a dragonboard410c device having wcn36xx
driver built as a loadable module along with a wifi manager in user-space
waiting for a wifi device (wlanX) to be active.

Sequence diagram for a particular kernel crash scenario:

    user-space  ieee80211_register_hw()  ieee80211_tasklet_handler()
    ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
       |                    |                 |
       |<---phy0----wiphy_register()          |
       |-----iwd if_add---->|                 |
       |                    |<---IRQ----(RX packet)
       |              Kernel crash            |
       |              due to unallocated      |
       |              workqueue.              |
       |                    |                 |
       |       alloc_ordered_workqueue()      |
       |                    |                 |
       |              Misc wiphy init.        |
       |                    |                 |
       |            ieee80211_if_add()        |
       |                    |                 |

As evident from above sequence diagram, this race condition isn't specific
to a particular wifi driver but rather the initialization sequence in
ieee80211_register_hw() needs to be fixed. So re-order the initialization
sequence and the updated sequence diagram would look like:

    user-space  ieee80211_register_hw()  ieee80211_tasklet_handler()
    ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
       |                    |                 |
       |       alloc_ordered_workqueue()      |
       |                    |                 |
       |              Misc wiphy init.        |
       |                    |                 |
       |<---phy0----wiphy_register()          |
       |-----iwd if_add---->|                 |
       |                    |<---IRQ----(RX packet)
       |                    |                 |
       |            ieee80211_if_add()        |
       |                    |                 |

Cc: stable@vger.kernel.org
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/1586254255-28713-1-git-send-email-sumit.garg@linaro.org
[Johannes: fix rtnl imbalances]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:26:26 +08:00
Kaixu Xia 590eaf1fec Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
2021-03-16 11:01:34 +08:00