* [syzbot] [wireless?] possible deadlock in ieee80211_remove_interfaces
@ 2024-09-05 20:10 syzbot
2025-01-17 3:58 ` syzbot
2025-01-17 19:07 ` syzbot
0 siblings, 2 replies; 6+ messages in thread
From: syzbot @ 2024-09-05 20:10 UTC (permalink / raw)
To: davem, edumazet, johannes, kuba, linux-kernel, linux-wireless,
netdev, pabeni, syzkaller-bugs
Hello,
syzbot found the following issue on:
HEAD commit: 431c1646e1f8 Linux 6.11-rc6
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=144a43db980000
kernel config: https://syzkaller.appspot.com/x/.config?x=931962fa28089080
dashboard link: https://syzkaller.appspot.com/bug?extid=5b9196ecf74447172a9a
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-431c1646.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/01c0dadd39ff/vmlinux-431c1646.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9e2259e440f7/bzImage-431c1646.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5b9196ecf74447172a9a@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
6.11.0-rc6-syzkaller #0 Not tainted
------------------------------------------------------
kworker/u32:7/1108 is trying to acquire lock:
but task is already holding lock:
ffff888055278768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:6014 [inline]
ffff888055278768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: ieee80211_remove_interfaces+0xfe/0x760 net/mac80211/iface.c:2262
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&rdev->wiphy.mtx){+.+.}-{3:3}:
dev_open net/core/dev.c:1510 [inline]
dev_open+0xf4/0x160 net/core/dev.c:1503
do_setlink+0xd24/0x4190 net/core/rtnetlink.c:2907
__rtnl_newlink+0xc35/0x1920 net/core/rtnetlink.c:3696
rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3743
rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6647
netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2550
netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357
netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (team->team_lock_key#10){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3133 [inline]
check_prevs_add kernel/locking/lockdep.c:3252 [inline]
validate_chain kernel/locking/lockdep.c:3868 [inline]
__lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142
lock_acquire kernel/locking/lockdep.c:5759 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
team_del_slave+0x31/0x1b0 drivers/net/team/team_core.c:1990
team_device_event+0xd0/0x770 drivers/net/team/team_core.c:2984
notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1994
call_netdevice_notifiers_extack net/core/dev.c:2032 [inline]
call_netdevice_notifiers net/core/dev.c:2046 [inline]
unregister_netdevice_many_notify+0x8bb/0x1e40 net/core/dev.c:11352
mac80211_hwsim_del_radio drivers/net/wireless/virtual/mac80211_hwsim.c:5625 [inline]
hwsim_exit_net+0x3ad/0x7d0 drivers/net/wireless/virtual/mac80211_hwsim.c:6505
ops_exit_list+0xb0/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xbb0 net/core/net_namespace.c:640
process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231
process_scheduled_works kernel/workqueue.c:3312 [inline]
worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
other info that might help us debug this:
---- ----
lock(&rdev->wiphy.mtx);
lock(team->team_lock_key#10);
*** DEADLOCK ***
5 locks held by kworker/u32:7/1108:
#0: ffff88801baf4948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206
stack backtrace:
CPU: 2 UID: 0 PID: 1108 Comm: kworker/u32:7 Not tainted 6.11.0-rc6-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: netns cleanup_net
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:93 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2186
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1994
call_netdevice_notifiers_extack net/core/dev.c:2032 [inline]
call_netdevice_notifiers net/core/dev.c:2046 [inline]
unregister_netdevice_many_notify+0x8bb/0x1e40 net/core/dev.c:11352
unregister_netdevice_many net/core/dev.c:11414 [inline]
unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11289
unregister_netdevice include/linux/netdevice.h:3129 [inline]
_cfg80211_unregister_wdev+0x624/0x7f0 net/wireless/core.c:1211
ieee80211_remove_interfaces+0x36d/0x760 net/mac80211/iface.c:2287
ieee80211_unregister_hw+0x55/0x3a0 net/mac80211/main.c:1669
mac80211_hwsim_del_radio drivers/net/wireless/virtual/mac80211_hwsim.c:5625 [inline]
hwsim_exit_net+0x3ad/0x7d0 drivers/net/wireless/virtual/mac80211_hwsim.c:6505
process_scheduled_works kernel/workqueue.c:3312 [inline]
worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [syzbot] [wireless?] possible deadlock in ieee80211_remove_interfaces
2024-09-05 20:10 [syzbot] [wireless?] possible deadlock in ieee80211_remove_interfaces syzbot
@ 2025-01-17 3:58 ` syzbot
2025-01-17 4:14 ` Eric Dumazet
2025-01-17 19:07 ` syzbot
1 sibling, 1 reply; 6+ messages in thread
From: syzbot @ 2025-01-17 3:58 UTC (permalink / raw)
To: davem, edumazet, johannes, kuba, linux-kernel, linux-wireless,
netdev, pabeni, syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: 8d20dcda404d selftests: drv-net-hw: inject pp_alloc_fail e..
git tree: net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=14ef5a18580000
kernel config: https://syzkaller.appspot.com/x/.config?x=c30f048a4f12891
dashboard link: https://syzkaller.appspot.com/bug?extid=5b9196ecf74447172a9a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15d7a1f8580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5ce07c743ced/disk-8d20dcda.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/66f2a9a35d5e/vmlinux-8d20dcda.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4c790c086a46/bzImage-8d20dcda.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5b9196ecf74447172a9a@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc7-syzkaller-01131-g8d20dcda404d #0 Not tainted
------------------------------------------------------
kworker/u8:6/3534 is trying to acquire lock:
ffffffff8fcb4a08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
ffffffff8fcb4a08 (rtnl_mutex){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
but task is already holding lock:
ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6034 [inline]
ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x129/0x700 net/mac80211/iface.c:2276
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&rdev->wiphy.mtx){+.+.}-{4:4}:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
wiphy_lock include/net/cfg80211.h:6019 [inline]
wiphy_register+0x1a49/0x27b0 net/wireless/core.c:1006
ieee80211_register_hw+0x30fb/0x3e10 net/mac80211/main.c:1582
mac80211_hwsim_new_radio+0x2a9f/0x4a90 drivers/net/wireless/virtual/mac80211_hwsim.c:5558
init_mac80211_hwsim+0x87a/0xb00 drivers/net/wireless/virtual/mac80211_hwsim.c:6910
do_one_initcall+0x248/0x870 init/main.c:1266
do_initcall_level+0x157/0x210 init/main.c:1328
do_initcalls+0x3f/0x80 init/main.c:1344
kernel_init_freeable+0x435/0x5d0 init/main.c:1577
kernel_init+0x1d/0x2b0 init/main.c:1466
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #0 (rtnl_mutex){+.+.}-{4:4}:
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
__lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
unregister_netdevice_many net/core/dev.c:11866 [inline]
unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11732
unregister_netdevice include/linux/netdevice.h:3320 [inline]
_cfg80211_unregister_wdev+0x163/0x590 net/wireless/core.c:1251
ieee80211_remove_interfaces+0x4ef/0x700 net/mac80211/iface.c:2301
ieee80211_unregister_hw+0x5d/0x2c0 net/mac80211/main.c:1676
mac80211_hwsim_del_radio+0x2c4/0x4c0 drivers/net/wireless/virtual/mac80211_hwsim.c:5664
hwsim_exit_net+0x5c1/0x670 drivers/net/wireless/virtual/mac80211_hwsim.c:6544
ops_exit_list net/core/net_namespace.c:172 [inline]
cleanup_net+0x812/0xd60 net/core/net_namespace.c:652
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
worker_thread+0x870/0xd30 kernel/workqueue.c:3398
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&rdev->wiphy.mtx);
lock(rtnl_mutex);
lock(&rdev->wiphy.mtx);
lock(rtnl_mutex);
*** DEADLOCK ***
4 locks held by kworker/u8:6/3534:
#0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317
#1: ffffc9000d507d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000d507d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317
#2: ffffffff8fca8290 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17a/0xd60 net/core/net_namespace.c:606
#3: ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6034 [inline]
#3: ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x129/0x700 net/mac80211/iface.c:2276
stack backtrace:
CPU: 1 UID: 0 PID: 3534 Comm: kworker/u8:6 Not tainted 6.13.0-rc7-syzkaller-01131-g8d20dcda404d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: netns cleanup_net
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
__lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
unregister_netdevice_many net/core/dev.c:11866 [inline]
unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11732
unregister_netdevice include/linux/netdevice.h:3320 [inline]
_cfg80211_unregister_wdev+0x163/0x590 net/wireless/core.c:1251
ieee80211_remove_interfaces+0x4ef/0x700 net/mac80211/iface.c:2301
ieee80211_unregister_hw+0x5d/0x2c0 net/mac80211/main.c:1676
mac80211_hwsim_del_radio+0x2c4/0x4c0 drivers/net/wireless/virtual/mac80211_hwsim.c:5664
hwsim_exit_net+0x5c1/0x670 drivers/net/wireless/virtual/mac80211_hwsim.c:6544
ops_exit_list net/core/net_namespace.c:172 [inline]
cleanup_net+0x812/0xd60 net/core/net_namespace.c:652
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
worker_thread+0x870/0xd30 kernel/workqueue.c:3398
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
hsr_slave_0: left promiscuous mode
hsr_slave_1: left promiscuous mode
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
batman_adv: batadv0: Removing interface: batadv_slave_1
veth1_macvtap: left promiscuous mode
veth0_macvtap: left promiscuous mode
veth1_vlan: left promiscuous mode
veth0_vlan: left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
bridge0: port 2(bridge_slave_1) entered blocking state
bridge0: port 2(bridge_slave_1) entered forwarding state
bridge0: port 1(bridge_slave_0) entered blocking state
bridge0: port 1(bridge_slave_0) entered forwarding state
bridge0: port 2(bridge_slave_1) entered blocking state
bridge0: port 2(bridge_slave_1) entered forwarding state
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [syzbot] [wireless?] possible deadlock in ieee80211_remove_interfaces
2025-01-17 3:58 ` syzbot
@ 2025-01-17 4:14 ` Eric Dumazet
2025-01-28 18:13 ` Aleksandr Nogikh
0 siblings, 1 reply; 6+ messages in thread
From: Eric Dumazet @ 2025-01-17 4:14 UTC (permalink / raw)
To: syzbot
Cc: davem, johannes, kuba, linux-kernel, linux-wireless, netdev,
pabeni, syzkaller-bugs
On Fri, Jan 17, 2025 at 4:58 AM syzbot
<syzbot+5b9196ecf74447172a9a@syzkaller.appspotmail.com> wrote:
>
> syzbot has found a reproducer for the following issue on:
>
> HEAD commit: 8d20dcda404d selftests: drv-net-hw: inject pp_alloc_fail e..
> git tree: net-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=14ef5a18580000
> kernel config: https://syzkaller.appspot.com/x/.config?x=c30f048a4f12891
> dashboard link: https://syzkaller.appspot.com/bug?extid=5b9196ecf74447172a9a
> compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15d7a1f8580000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/5ce07c743ced/disk-8d20dcda.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/66f2a9a35d5e/vmlinux-8d20dcda.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/4c790c086a46/bzImage-8d20dcda.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+5b9196ecf74447172a9a@syzkaller.appspotmail.com
>
> ======================================================
> WARNING: possible circular locking dependency detected
> 6.13.0-rc7-syzkaller-01131-g8d20dcda404d #0 Not tainted
> ------------------------------------------------------
> kworker/u8:6/3534 is trying to acquire lock:
> ffffffff8fcb4a08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
> ffffffff8fcb4a08 (rtnl_mutex){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
>
> but task is already holding lock:
> ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6034 [inline]
> ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x129/0x700 net/mac80211/iface.c:2276
>
> which lock already depends on the new lock.
>
>
> the existing dependency chain (in reverse order) is:
>
> -> #1 (&rdev->wiphy.mtx){+.+.}-{4:4}:
> lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
> __mutex_lock_common kernel/locking/mutex.c:585 [inline]
> __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
> wiphy_lock include/net/cfg80211.h:6019 [inline]
> wiphy_register+0x1a49/0x27b0 net/wireless/core.c:1006
> ieee80211_register_hw+0x30fb/0x3e10 net/mac80211/main.c:1582
> mac80211_hwsim_new_radio+0x2a9f/0x4a90 drivers/net/wireless/virtual/mac80211_hwsim.c:5558
> init_mac80211_hwsim+0x87a/0xb00 drivers/net/wireless/virtual/mac80211_hwsim.c:6910
> do_one_initcall+0x248/0x870 init/main.c:1266
> do_initcall_level+0x157/0x210 init/main.c:1328
> do_initcalls+0x3f/0x80 init/main.c:1344
> kernel_init_freeable+0x435/0x5d0 init/main.c:1577
> kernel_init+0x1d/0x2b0 init/main.c:1466
> ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
>
> -> #0 (rtnl_mutex){+.+.}-{4:4}:
> check_prev_add kernel/locking/lockdep.c:3161 [inline]
> check_prevs_add kernel/locking/lockdep.c:3280 [inline]
> validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
> __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
> lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
> __mutex_lock_common kernel/locking/mutex.c:585 [inline]
> __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
> rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
> unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
> unregister_netdevice_many net/core/dev.c:11866 [inline]
> unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11732
> unregister_netdevice include/linux/netdevice.h:3320 [inline]
> _cfg80211_unregister_wdev+0x163/0x590 net/wireless/core.c:1251
> ieee80211_remove_interfaces+0x4ef/0x700 net/mac80211/iface.c:2301
> ieee80211_unregister_hw+0x5d/0x2c0 net/mac80211/main.c:1676
> mac80211_hwsim_del_radio+0x2c4/0x4c0 drivers/net/wireless/virtual/mac80211_hwsim.c:5664
> hwsim_exit_net+0x5c1/0x670 drivers/net/wireless/virtual/mac80211_hwsim.c:6544
> ops_exit_list net/core/net_namespace.c:172 [inline]
> cleanup_net+0x812/0xd60 net/core/net_namespace.c:652
> process_one_work kernel/workqueue.c:3236 [inline]
> process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
> worker_thread+0x870/0xd30 kernel/workqueue.c:3398
> kthread+0x2f0/0x390 kernel/kthread.c:389
> ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
>
> other info that might help us debug this:
>
> Possible unsafe locking scenario:
>
> CPU0 CPU1
> ---- ----
> lock(&rdev->wiphy.mtx);
> lock(rtnl_mutex);
> lock(&rdev->wiphy.mtx);
> lock(rtnl_mutex);
>
> *** DEADLOCK ***
>
> 4 locks held by kworker/u8:6/3534:
> #0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
> #0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317
> #1: ffffc9000d507d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
> #1: ffffc9000d507d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317
> #2: ffffffff8fca8290 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17a/0xd60 net/core/net_namespace.c:606
> #3: ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6034 [inline]
> #3: ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x129/0x700 net/mac80211/iface.c:2276
>
> stack backtrace:
> CPU: 1 UID: 0 PID: 3534 Comm: kworker/u8:6 Not tainted 6.13.0-rc7-syzkaller-01131-g8d20dcda404d #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
> Workqueue: netns cleanup_net
> Call Trace:
> <TASK>
> __dump_stack lib/dump_stack.c:94 [inline]
> dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
> print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
> check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
> check_prev_add kernel/locking/lockdep.c:3161 [inline]
> check_prevs_add kernel/locking/lockdep.c:3280 [inline]
> validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
> __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
> lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
> __mutex_lock_common kernel/locking/mutex.c:585 [inline]
> __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
> rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
> unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
> unregister_netdevice_many net/core/dev.c:11866 [inline]
> unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11732
> unregister_netdevice include/linux/netdevice.h:3320 [inline]
> _cfg80211_unregister_wdev+0x163/0x590 net/wireless/core.c:1251
> ieee80211_remove_interfaces+0x4ef/0x700 net/mac80211/iface.c:2301
> ieee80211_unregister_hw+0x5d/0x2c0 net/mac80211/main.c:1676
> mac80211_hwsim_del_radio+0x2c4/0x4c0 drivers/net/wireless/virtual/mac80211_hwsim.c:5664
> hwsim_exit_net+0x5c1/0x670 drivers/net/wireless/virtual/mac80211_hwsim.c:6544
> ops_exit_list net/core/net_namespace.c:172 [inline]
> cleanup_net+0x812/0xd60 net/core/net_namespace.c:652
> process_one_work kernel/workqueue.c:3236 [inline]
> process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
> worker_thread+0x870/0xd30 kernel/workqueue.c:3398
> kthread+0x2f0/0x390 kernel/kthread.c:389
> ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
> </TASK>
> hsr_slave_0: left promiscuous mode
> hsr_slave_1: left promiscuous mode
> batman_adv: batadv0: Interface deactivated: batadv_slave_0
> batman_adv: batadv0: Removing interface: batadv_slave_0
> batman_adv: batadv0: Interface deactivated: batadv_slave_1
> batman_adv: batadv0: Removing interface: batadv_slave_1
> veth1_macvtap: left promiscuous mode
> veth0_macvtap: left promiscuous mode
> veth1_vlan: left promiscuous mode
> veth0_vlan: left promiscuous mode
> team0 (unregistering): Port device team_slave_1 removed
> team0 (unregistering): Port device team_slave_0 removed
> bridge0: port 2(bridge_slave_1) entered blocking state
> bridge0: port 2(bridge_slave_1) entered forwarding state
> bridge0: port 1(bridge_slave_0) entered blocking state
> bridge0: port 1(bridge_slave_0) entered forwarding state
> bridge0: port 2(bridge_slave_1) entered blocking state
> bridge0: port 2(bridge_slave_1) entered forwarding state
>
>
> ---
> If you want syzbot to run the reproducer, reply with:
> #syz test: git://repo/address.git branch-or-commit-hash
> If you attach or paste a git patch, syzbot will apply it before testing.
This repro is for another bug I think, caused by my recent commits in net-next:
83419b61d187ce22aa3da5ffdda850fca3a12600 net: reduce RTNL hold
duration in unregister_netdevice_many_notify() (part 2)
ae646f1a0bb97401bac0044bbe2a179a1e38b408 net: reduce RTNL hold
duration in unregister_netdevice_many_notify() (part 1)
cfa579f6665635b72d4a075fc91eb144c2b0f74e net: no longer hold RTNL
while calling flush_all_backlogs()
cleanup_net()
rtnl_lock();
mutex_lock(subsystem_mutex);
unregister_netdevice();
rtnl_unlock(); // LOCKDEP violation
rtnl_lock();
I will work today on a fix, auditing all unregister_netdevice() and
unregister_netdevice_many()
and select which of them can safely opt-in for a variant which _can_
temporarily release RTNL.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [syzbot] [wireless?] possible deadlock in ieee80211_remove_interfaces
2024-09-05 20:10 [syzbot] [wireless?] possible deadlock in ieee80211_remove_interfaces syzbot
2025-01-17 3:58 ` syzbot
@ 2025-01-17 19:07 ` syzbot
1 sibling, 0 replies; 6+ messages in thread
From: syzbot @ 2025-01-17 19:07 UTC (permalink / raw)
To: davem, edumazet, johannes, kuba, linux-kernel, linux-wireless,
netdev, pabeni, syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: 8d20dcda404d selftests: drv-net-hw: inject pp_alloc_fail e..
git tree: net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=13ff9fc4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=c30f048a4f12891
dashboard link: https://syzkaller.appspot.com/bug?extid=5b9196ecf74447172a9a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17ff9fc4580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13ca3a18580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5ce07c743ced/disk-8d20dcda.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/66f2a9a35d5e/vmlinux-8d20dcda.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4c790c086a46/bzImage-8d20dcda.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5b9196ecf74447172a9a@syzkaller.appspotmail.com
bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
bond0 (unregistering): Released all slaves
======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc7-syzkaller-01131-g8d20dcda404d #0 Not tainted
------------------------------------------------------
kworker/u8:6/1143 is trying to acquire lock:
ffffffff8fcb4a08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
ffffffff8fcb4a08 (rtnl_mutex){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
but task is already holding lock:
ffff888027260768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6034 [inline]
ffff888027260768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x129/0x700 net/mac80211/iface.c:2276
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&rdev->wiphy.mtx){+.+.}-{4:4}:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
wiphy_lock include/net/cfg80211.h:6019 [inline]
wiphy_register+0x1a49/0x27b0 net/wireless/core.c:1006
ieee80211_register_hw+0x30fb/0x3e10 net/mac80211/main.c:1582
mac80211_hwsim_new_radio+0x2a9f/0x4a90 drivers/net/wireless/virtual/mac80211_hwsim.c:5558
init_mac80211_hwsim+0x87a/0xb00 drivers/net/wireless/virtual/mac80211_hwsim.c:6910
do_one_initcall+0x248/0x870 init/main.c:1266
do_initcall_level+0x157/0x210 init/main.c:1328
do_initcalls+0x3f/0x80 init/main.c:1344
kernel_init_freeable+0x435/0x5d0 init/main.c:1577
kernel_init+0x1d/0x2b0 init/main.c:1466
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #0 (rtnl_mutex){+.+.}-{4:4}:
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
__lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
unregister_netdevice_many net/core/dev.c:11866 [inline]
unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11732
unregister_netdevice include/linux/netdevice.h:3320 [inline]
_cfg80211_unregister_wdev+0x163/0x590 net/wireless/core.c:1251
ieee80211_remove_interfaces+0x4ef/0x700 net/mac80211/iface.c:2301
ieee80211_unregister_hw+0x5d/0x2c0 net/mac80211/main.c:1676
mac80211_hwsim_del_radio+0x2c4/0x4c0 drivers/net/wireless/virtual/mac80211_hwsim.c:5664
hwsim_exit_net+0x5c1/0x670 drivers/net/wireless/virtual/mac80211_hwsim.c:6544
ops_exit_list net/core/net_namespace.c:172 [inline]
cleanup_net+0x812/0xd60 net/core/net_namespace.c:652
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
worker_thread+0x870/0xd30 kernel/workqueue.c:3398
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&rdev->wiphy.mtx);
lock(rtnl_mutex);
lock(&rdev->wiphy.mtx);
lock(rtnl_mutex);
*** DEADLOCK ***
4 locks held by kworker/u8:6/1143:
#0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317
#1: ffffc900041ffd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc900041ffd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317
#2: ffffffff8fca8290 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17a/0xd60 net/core/net_namespace.c:606
#3: ffff888027260768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6034 [inline]
#3: ffff888027260768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x129/0x700 net/mac80211/iface.c:2276
stack backtrace:
CPU: 0 UID: 0 PID: 1143 Comm: kworker/u8:6 Not tainted 6.13.0-rc7-syzkaller-01131-g8d20dcda404d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: netns cleanup_net
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
__lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
unregister_netdevice_many net/core/dev.c:11866 [inline]
unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11732
unregister_netdevice include/linux/netdevice.h:3320 [inline]
_cfg80211_unregister_wdev+0x163/0x590 net/wireless/core.c:1251
ieee80211_remove_interfaces+0x4ef/0x700 net/mac80211/iface.c:2301
ieee80211_unregister_hw+0x5d/0x2c0 net/mac80211/main.c:1676
mac80211_hwsim_del_radio+0x2c4/0x4c0 drivers/net/wireless/virtual/mac80211_hwsim.c:5664
hwsim_exit_net+0x5c1/0x670 drivers/net/wireless/virtual/mac80211_hwsim.c:6544
ops_exit_list net/core/net_namespace.c:172 [inline]
cleanup_net+0x812/0xd60 net/core/net_namespace.c:652
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
worker_thread+0x870/0xd30 kernel/workqueue.c:3398
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [syzbot] [wireless?] possible deadlock in ieee80211_remove_interfaces
2025-01-17 4:14 ` Eric Dumazet
@ 2025-01-28 18:13 ` Aleksandr Nogikh
2025-01-28 18:16 ` Eric Dumazet
0 siblings, 1 reply; 6+ messages in thread
From: Aleksandr Nogikh @ 2025-01-28 18:13 UTC (permalink / raw)
To: Eric Dumazet
Cc: syzbot, davem, johannes, kuba, linux-kernel, linux-wireless,
netdev, pabeni, syzkaller-bugs, Dmitry Vyukov
Hi Eric,
On Fri, Jan 17, 2025 at 5:14 AM 'Eric Dumazet' via syzkaller-bugs
<syzkaller-bugs@googlegroups.com> wrote:
>
> On Fri, Jan 17, 2025 at 4:58 AM syzbot
> <syzbot+5b9196ecf74447172a9a@syzkaller.appspotmail.com> wrote:
> >
> > syzbot has found a reproducer for the following issue on:
> >
> > HEAD commit: 8d20dcda404d selftests: drv-net-hw: inject pp_alloc_fail e..
> > git tree: net-next
> > console output: https://syzkaller.appspot.com/x/log.txt?x=14ef5a18580000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=c30f048a4f12891
> > dashboard link: https://syzkaller.appspot.com/bug?extid=5b9196ecf74447172a9a
> > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15d7a1f8580000
> >
> > Downloadable assets:
> > disk image: https://storage.googleapis.com/syzbot-assets/5ce07c743ced/disk-8d20dcda.raw.xz
> > vmlinux: https://storage.googleapis.com/syzbot-assets/66f2a9a35d5e/vmlinux-8d20dcda.xz
> > kernel image: https://storage.googleapis.com/syzbot-assets/4c790c086a46/bzImage-8d20dcda.xz
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: syzbot+5b9196ecf74447172a9a@syzkaller.appspotmail.com
> >
> > ======================================================
> > WARNING: possible circular locking dependency detected
> > 6.13.0-rc7-syzkaller-01131-g8d20dcda404d #0 Not tainted
> > ------------------------------------------------------
> > kworker/u8:6/3534 is trying to acquire lock:
> > ffffffff8fcb4a08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
> > ffffffff8fcb4a08 (rtnl_mutex){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
> >
> > but task is already holding lock:
> > ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6034 [inline]
> > ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x129/0x700 net/mac80211/iface.c:2276
> >
> > which lock already depends on the new lock.
> >
> >
> > the existing dependency chain (in reverse order) is:
> >
> > -> #1 (&rdev->wiphy.mtx){+.+.}-{4:4}:
> > lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
> > __mutex_lock_common kernel/locking/mutex.c:585 [inline]
> > __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
> > wiphy_lock include/net/cfg80211.h:6019 [inline]
> > wiphy_register+0x1a49/0x27b0 net/wireless/core.c:1006
> > ieee80211_register_hw+0x30fb/0x3e10 net/mac80211/main.c:1582
> > mac80211_hwsim_new_radio+0x2a9f/0x4a90 drivers/net/wireless/virtual/mac80211_hwsim.c:5558
> > init_mac80211_hwsim+0x87a/0xb00 drivers/net/wireless/virtual/mac80211_hwsim.c:6910
> > do_one_initcall+0x248/0x870 init/main.c:1266
> > do_initcall_level+0x157/0x210 init/main.c:1328
> > do_initcalls+0x3f/0x80 init/main.c:1344
> > kernel_init_freeable+0x435/0x5d0 init/main.c:1577
> > kernel_init+0x1d/0x2b0 init/main.c:1466
> > ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
> > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
> >
> > -> #0 (rtnl_mutex){+.+.}-{4:4}:
> > check_prev_add kernel/locking/lockdep.c:3161 [inline]
> > check_prevs_add kernel/locking/lockdep.c:3280 [inline]
> > validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
> > __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
> > lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
> > __mutex_lock_common kernel/locking/mutex.c:585 [inline]
> > __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
> > rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
> > unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
> > unregister_netdevice_many net/core/dev.c:11866 [inline]
> > unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11732
> > unregister_netdevice include/linux/netdevice.h:3320 [inline]
> > _cfg80211_unregister_wdev+0x163/0x590 net/wireless/core.c:1251
> > ieee80211_remove_interfaces+0x4ef/0x700 net/mac80211/iface.c:2301
> > ieee80211_unregister_hw+0x5d/0x2c0 net/mac80211/main.c:1676
> > mac80211_hwsim_del_radio+0x2c4/0x4c0 drivers/net/wireless/virtual/mac80211_hwsim.c:5664
> > hwsim_exit_net+0x5c1/0x670 drivers/net/wireless/virtual/mac80211_hwsim.c:6544
> > ops_exit_list net/core/net_namespace.c:172 [inline]
> > cleanup_net+0x812/0xd60 net/core/net_namespace.c:652
> > process_one_work kernel/workqueue.c:3236 [inline]
> > process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
> > worker_thread+0x870/0xd30 kernel/workqueue.c:3398
> > kthread+0x2f0/0x390 kernel/kthread.c:389
> > ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
> > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
> >
> > other info that might help us debug this:
> >
> > Possible unsafe locking scenario:
> >
> > CPU0 CPU1
> > ---- ----
> > lock(&rdev->wiphy.mtx);
> > lock(rtnl_mutex);
> > lock(&rdev->wiphy.mtx);
> > lock(rtnl_mutex);
> >
> > *** DEADLOCK ***
> >
> > 4 locks held by kworker/u8:6/3534:
> > #0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
> > #0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317
> > #1: ffffc9000d507d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
> > #1: ffffc9000d507d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317
> > #2: ffffffff8fca8290 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17a/0xd60 net/core/net_namespace.c:606
> > #3: ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6034 [inline]
> > #3: ffff8880216b0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x129/0x700 net/mac80211/iface.c:2276
> >
> > stack backtrace:
> > CPU: 1 UID: 0 PID: 3534 Comm: kworker/u8:6 Not tainted 6.13.0-rc7-syzkaller-01131-g8d20dcda404d #0
> > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
> > Workqueue: netns cleanup_net
> > Call Trace:
> > <TASK>
> > __dump_stack lib/dump_stack.c:94 [inline]
> > dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
> > print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
> > check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
> > check_prev_add kernel/locking/lockdep.c:3161 [inline]
> > check_prevs_add kernel/locking/lockdep.c:3280 [inline]
> > validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
> > __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
> > lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
> > __mutex_lock_common kernel/locking/mutex.c:585 [inline]
> > __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735
> > rtnl_acquire_if_cleanup_net net/core/dev.c:10281 [inline]
> > unregister_netdevice_many_notify+0xac2/0x2030 net/core/dev.c:11783
> > unregister_netdevice_many net/core/dev.c:11866 [inline]
> > unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11732
> > unregister_netdevice include/linux/netdevice.h:3320 [inline]
> > _cfg80211_unregister_wdev+0x163/0x590 net/wireless/core.c:1251
> > ieee80211_remove_interfaces+0x4ef/0x700 net/mac80211/iface.c:2301
> > ieee80211_unregister_hw+0x5d/0x2c0 net/mac80211/main.c:1676
> > mac80211_hwsim_del_radio+0x2c4/0x4c0 drivers/net/wireless/virtual/mac80211_hwsim.c:5664
> > hwsim_exit_net+0x5c1/0x670 drivers/net/wireless/virtual/mac80211_hwsim.c:6544
> > ops_exit_list net/core/net_namespace.c:172 [inline]
> > cleanup_net+0x812/0xd60 net/core/net_namespace.c:652
> > process_one_work kernel/workqueue.c:3236 [inline]
> > process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
> > worker_thread+0x870/0xd30 kernel/workqueue.c:3398
> > kthread+0x2f0/0x390 kernel/kthread.c:389
> > ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
> > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
> > </TASK>
> > hsr_slave_0: left promiscuous mode
> > hsr_slave_1: left promiscuous mode
> > batman_adv: batadv0: Interface deactivated: batadv_slave_0
> > batman_adv: batadv0: Removing interface: batadv_slave_0
> > batman_adv: batadv0: Interface deactivated: batadv_slave_1
> > batman_adv: batadv0: Removing interface: batadv_slave_1
> > veth1_macvtap: left promiscuous mode
> > veth0_macvtap: left promiscuous mode
> > veth1_vlan: left promiscuous mode
> > veth0_vlan: left promiscuous mode
> > team0 (unregistering): Port device team_slave_1 removed
> > team0 (unregistering): Port device team_slave_0 removed
> > bridge0: port 2(bridge_slave_1) entered blocking state
> > bridge0: port 2(bridge_slave_1) entered forwarding state
> > bridge0: port 1(bridge_slave_0) entered blocking state
> > bridge0: port 1(bridge_slave_0) entered forwarding state
> > bridge0: port 2(bridge_slave_1) entered blocking state
> > bridge0: port 2(bridge_slave_1) entered forwarding state
> >
> >
> > ---
> > If you want syzbot to run the reproducer, reply with:
> > #syz test: git://repo/address.git branch-or-commit-hash
> > If you attach or paste a git patch, syzbot will apply it before testing.
>
> This repro is for another bug I think, caused by my recent commits in net-next:
>
> 83419b61d187ce22aa3da5ffdda850fca3a12600 net: reduce RTNL hold
> duration in unregister_netdevice_many_notify() (part 2)
> ae646f1a0bb97401bac0044bbe2a179a1e38b408 net: reduce RTNL hold
> duration in unregister_netdevice_many_notify() (part 1)
> cfa579f6665635b72d4a075fc91eb144c2b0f74e net: no longer hold RTNL
> while calling flush_all_backlogs()
>
> cleanup_net()
> rtnl_lock();
> mutex_lock(subsystem_mutex);
>
> unregister_netdevice();
>
> rtnl_unlock(); // LOCKDEP violation
> rtnl_lock();
>
> I will work today on a fix, auditing all unregister_netdevice() and
> unregister_netdevice_many()
> and select which of them can safely opt-in for a variant which _can_
> temporarily release RTNL.
>
Could you please share what's the current situation with the fix?
The bug unfortunately keeps on stalling the fuzzing on syzbot by
causing 70+% of all daily crashes.
--
Aleksandr
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [syzbot] [wireless?] possible deadlock in ieee80211_remove_interfaces
2025-01-28 18:13 ` Aleksandr Nogikh
@ 2025-01-28 18:16 ` Eric Dumazet
0 siblings, 0 replies; 6+ messages in thread
From: Eric Dumazet @ 2025-01-28 18:16 UTC (permalink / raw)
To: Aleksandr Nogikh
Cc: syzbot, davem, johannes, kuba, linux-kernel, linux-wireless,
netdev, pabeni, syzkaller-bugs, Dmitry Vyukov
On Tue, Jan 28, 2025 at 7:13 PM Aleksandr Nogikh <nogikh@google.com> wrote:
>
> Hi Eric,
>
>
> Could you please share what's the current situation with the fix?
> The bug unfortunately keeps on stalling the fuzzing on syzbot by
> causing 70+% of all daily crashes.
I think I am going to send a revert for the net tree, and revisit this
stuff for the next cycle.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2025-01-28 18:16 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-09-05 20:10 [syzbot] [wireless?] possible deadlock in ieee80211_remove_interfaces syzbot
2025-01-17 3:58 ` syzbot
2025-01-17 4:14 ` Eric Dumazet
2025-01-28 18:13 ` Aleksandr Nogikh
2025-01-28 18:16 ` Eric Dumazet
2025-01-17 19:07 ` syzbot
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).