WARNING in cfg80211_bss_update

Status: upstream: reported C repro on 2025/12/29 19:57
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+8d9fab724d08da609d8e@syzkaller.appspotmail.com
First crash: 268d, last: 2d04h
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2026/01/03 upstream (ToT) aacb0a6d604a C [report] WARNING in __cfg80211_bss_update
2026/07/09 upstream (ToT) 0e35b9b6ec0f C Failed due to an error; will retry later
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in cfg80211_bss_update -1 4 2d02h 2d06h 0/3 upstream: reported on 2026/09/22 13:14
upstream WARNING in cfg80211_bss_update (3) wireless -1 1 1256d 1252d 0/29 auto-obsoleted due to no activity on 2023/08/15 12:15
upstream WARNING in cfg80211_bss_update wireless -1 1 2076d 2074d 0/29 auto-closed as invalid on 2021/05/17 12:37
upstream WARNING in cfg80211_bss_update (2) wireless -1 2 1740d 1823d 0/29 auto-closed as invalid on 2022/04/18 00:39

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 39 at net/wireless/scan.c:518 cfg80211_bss_expire_oldest net/wireless/scan.c:518 [inline]
WARNING: CPU: 0 PID: 39 at net/wireless/scan.c:518 cfg80211_bss_update+0x1cc0/0x1ccc net/wireless/scan.c:1908
Modules linked in:
CPU: 0 PID: 39 Comm: kworker/u4:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026
Workqueue: events_unbound cfg80211_wiphy_work
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : cfg80211_bss_expire_oldest net/wireless/scan.c:518 [inline]
pc : cfg80211_bss_update+0x1cc0/0x1ccc net/wireless/scan.c:1908
lr : cfg80211_bss_expire_oldest net/wireless/scan.c:518 [inline]
lr : cfg80211_bss_update+0x1cc0/0x1ccc net/wireless/scan.c:1908
sp : ffff80001e0072b0
x29: ffff80001e007320 x28: dfff800000000000 x27: ffff0000d33f8190
x26: 1ffff00002a78070 x25: 0000000000000001 x24: 0000000000000000
x23: ffff0000d33f8190 x22: ffff80001e007440 x21: ffff0000d33f81a0
x20: ffff0000cc413000 x19: ffff0000d644e050 x18: 1fffe00033e6997e
x17: ffff8000113f999c x16: ffff8000082dbd78 x15: 0000000000000000
x14: 0000000000000001 x13: 1fffe0001ac89c0a x12: 0000000000000000
x11: ff00800011252f1c x10: 0000000000000000 x9 : ffff800011252f1c
x8 : ffff0000c4328000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff0000cc4130c8 x4 : ffff80001e007508 x3 : ffff800011251b64
x2 : 0000000000000000 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
 cfg80211_bss_expire_oldest net/wireless/scan.c:518 [inline]
 cfg80211_bss_update+0x1cc0/0x1ccc net/wireless/scan.c:1908
 cfg80211_inform_single_bss_frame_data net/wireless/scan.c:2509 [inline]
 cfg80211_inform_bss_frame_data+0x890/0x10f8 net/wireless/scan.c:2542
 ieee80211_bss_info_update+0x640/0xa7c net/mac80211/scan.c:190
 ieee80211_rx_bss_info net/mac80211/ibss.c:1120 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1609 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x143c/0x2608 net/mac80211/ibss.c:1638
 ieee80211_iface_process_skb net/mac80211/iface.c:1685 [inline]
 ieee80211_iface_work+0x5a8/0xa4c net/mac80211/iface.c:1739
 cfg80211_wiphy_work+0x1e0/0x220 net/wireless/core.c:433
 process_one_work+0x7e4/0x13bc kernel/workqueue.c:2292
 worker_thread+0x8cc/0xfe8 kernel/workqueue.c:2439
 kthread+0x254/0x2e0 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850
irq event stamp: 612765
hardirqs last  enabled at (612764): [<ffff800011c9da4c>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
hardirqs last  enabled at (612764): [<ffff800011c9da4c>] _raw_spin_unlock_irqrestore+0x48/0xac kernel/locking/spinlock.c:194
hardirqs last disabled at (612765): [<ffff800011bb2834>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (612746): [<ffff8000113fae10>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (612746): [<ffff8000113fae10>] ieee80211_ibss_work+0x2a8/0xd68 net/mac80211/ibss.c:1701
softirqs last disabled at (612762): [<ffff8000112512e0>] spin_lock_bh include/linux/spinlock.h:356 [inline]
softirqs last disabled at (612762): [<ffff8000112512e0>] cfg80211_bss_update+0x84/0x1ccc net/wireless/scan.c:1837
---[ end trace 0000000000000000 ]---

Crashes (13):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/22 15:07 linux-6.1.y 1a8763b93150 e12281bd .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in cfg80211_bss_update
2025/12/29 19:57 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in cfg80211_bss_update
2026/09/22 12:34 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in cfg80211_bss_update
2026/09/22 12:34 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in cfg80211_bss_update
2026/09/22 12:01 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in cfg80211_bss_update
2026/09/22 11:20 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in cfg80211_bss_update
2026/09/22 12:57 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in cfg80211_bss_update
2026/09/22 12:48 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in cfg80211_bss_update
2026/09/22 12:46 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in cfg80211_bss_update
2026/09/22 12:46 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in cfg80211_bss_update
2026/09/22 12:40 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in cfg80211_bss_update
2026/09/22 12:26 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in cfg80211_bss_update
2026/09/22 12:26 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in cfg80211_bss_update
* Struck through repros no longer work on HEAD.