WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface

Status: upstream: reported C repro on 2026/02/11 18:46
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+95df812296710ce46e07@syzkaller.appspotmail.com
First crash: 201d, last: now
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2026/02/14 linux-6.6.y (ToT) 1b4ef5214f17 C [report] WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/14 upstream (ToT) 770aaedb461a C Didn't crash
▶ ▼ Fix bisection attempts (3)
Created Duration User Patch Repo Result
2026/04/17 04:51 1m fix candidate upstream error job log
2026/03/17 14:34 1m fix candidate upstream error job log
2026/02/15 14:22 12m fix candidate upstream error job log

Sample crash report:
=============================
WARNING: suspicious RCU usage
syzkaller #0 Not tainted
-----------------------------
net/mac80211/iface.c:378 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz.0.17/5939:
 #0: ffffffff8e3d70c8 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x7a4/0x1140 net/core/dev_ioctl.c:769

stack backtrace:
CPU: 1 PID: 5939 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 lockdep_rcu_suspicious+0x1e1/0x300 kernel/locking/lockdep.c:6731
 ieee80211_check_concurrent_iface+0x46b/0x950 net/mac80211/iface.c:378
 ieee80211_open+0xc1/0x200 net/mac80211/iface.c:466
 __dev_open+0x2cb/0x430 net/core/dev.c:1519
 __dev_change_flags+0x1e8/0x6a0 net/core/dev.c:8723
 dev_change_flags+0x7c/0x1a0 net/core/dev.c:8795
 dev_ioctl+0x7b4/0x1140 net/core/dev_ioctl.c:770
 sock_do_ioctl+0x239/0x310 net/socket.c:1234
 sock_ioctl+0x5be/0x7e0 net/socket.c:1341
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1ff5b9e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffefeb44b88 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1ff5e25fa0 RCX: 00007f1ff5b9e0d9
RDX: 0000200000002280 RSI: 0000000000008914 RDI: 0000000000000004
RBP: 00007f1ff5c35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1ff5e25fac R14: 00007f1ff5e25fa0 R15: 00007f1ff5e25fa0
 </TASK>
mac80211_hwsim hwsim4 syzkaller0: entered promiscuous mode
mac80211_hwsim hwsim4 syzkaller0: entered allmulticast mode

Crashes (3212):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/08 03:42 linux-6.6.y 6436c12a2ced e4ef95d6 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/05/27 10:01 linux-6.6.y 0a40c6fbd105 2b01f00e .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/16 03:42 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/15 23:10 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/15 18:34 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/15 13:52 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/15 09:12 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/15 04:33 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/14 23:54 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/14 18:47 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/14 14:10 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/14 09:17 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/09/01 15:06 linux-6.6.y a4a971135a2f 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/09/01 15:04 linux-6.6.y a4a971135a2f 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/09/01 13:22 linux-6.6.y a4a971135a2f 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/09/01 04:56 linux-6.6.y a4a971135a2f 316d9396 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/09/01 02:43 linux-6.6.y a4a971135a2f 316d9396 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/31 23:26 linux-6.6.y a4a971135a2f 316d9396 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/31 19:42 linux-6.6.y a4a971135a2f 316d9396 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/31 18:37 linux-6.6.y a4a971135a2f 316d9396 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/31 10:38 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/31 04:01 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/30 01:47 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/29 16:56 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/29 14:07 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/29 07:53 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/29 04:52 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/29 02:27 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/28 23:51 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/28 18:26 linux-6.6.y a4a971135a2f e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/28 15:00 linux-6.6.y a4a971135a2f e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/28 11:24 linux-6.6.y a4a971135a2f e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/28 11:22 linux-6.6.y a4a971135a2f e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/28 02:16 linux-6.6.y 93e0c9521fa8 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/27 22:35 linux-6.6.y 93e0c9521fa8 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/27 19:02 linux-6.6.y 93e0c9521fa8 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/27 16:50 linux-6.6.y 93e0c9521fa8 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/27 15:46 linux-6.6.y 93e0c9521fa8 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/27 12:19 linux-6.6.y dc6160265ffc 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/27 08:05 linux-6.6.y dc6160265ffc a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/27 05:13 linux-6.6.y dc6160265ffc a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/26 16:12 linux-6.6.y dc6160265ffc a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/26 15:14 linux-6.6.y dc6160265ffc a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/26 10:05 linux-6.6.y dc6160265ffc 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/26 09:59 linux-6.6.y dc6160265ffc 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/26 03:46 linux-6.6.y dc6160265ffc 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/26 02:45 linux-6.6.y dc6160265ffc 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/25 15:44 linux-6.6.y dc6160265ffc a9a1fc32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/25 15:43 linux-6.6.y dc6160265ffc a9a1fc32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/25 14:39 linux-6.6.y dc6160265ffc a9a1fc32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/25 07:01 linux-6.6.y dc6160265ffc 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/25 02:53 linux-6.6.y dc6160265ffc 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/25 01:51 linux-6.6.y dc6160265ffc 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/08/24 16:57 linux-6.6.y dc6160265ffc b55bd4c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
2026/02/11 18:46 linux-6.6.y 1b4ef5214f17 75707236 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: suspicious RCU usage in ieee80211_check_concurrent_iface
* Struck through repros no longer work on HEAD.