syzbot


WARNING in cfg80211_chandef_dfs_required (2)

Status: upstream: reported on 2026/03/29 04:32
Subsystems: wireless
[Documentation on labels]
Reported-by: syzbot+02a1a03b8622d3c7d1c9@syzkaller.appspotmail.com
First crash: 28d, last: 13h44m
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [wireless?] WARNING in cfg80211_chandef_dfs_required (2) 0 (1) 2026/03/29 04:32
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in cfg80211_chandef_dfs_required wireless -1 4 782d 827d 0/29 auto-obsoleted due to no activity on 2024/06/08 10:12

Sample crash report:
------------[ cut here ]------------
!cfg80211_chandef_valid(chandef)
WARNING: net/wireless/chan.c:796 at cfg80211_chandef_dfs_required+0xe06/0xec0 net/wireless/chan.c:796, CPU#0: syz.8.6071/26398
Modules linked in:
CPU: 0 UID: 0 PID: 26398 Comm: syz.8.6071 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:cfg80211_chandef_dfs_required+0xe06/0xec0 net/wireless/chan.c:796
Code: de e8 9e 1f b6 f6 48 83 fb 3f 0f 87 aa 00 00 00 e8 4f 1b b6 f6 b8 01 00 00 00 89 d9 48 d3 e0 e9 41 f4 ff ff e8 3b 1b b6 f6 90 <0f> 0b 90 b8 ea ff ff ff e9 2e f4 ff ff e8 68 80 a6 00 89 d1 80 e1
RSP: 0018:ffffc9000d61f700 EFLAGS: 00010283
RAX: ffffffff8b0fa375 RBX: ffff888028bed7f8 RCX: 0000000000080000
RDX: ffffc9000dee1000 RSI: 000000000000061f RDI: 0000000000000620
RBP: ffffc9000d61f890 R08: ffffffff8225238f R09: ffff8880b863f5a8
R10: dffffc0000000000 R11: ffffed1011c7054a R12: 0000000000000006
R13: dffffc0000000000 R14: ffffc9000d61fa00 R15: dffffc0000000000
FS:  00007f07ea7c36c0(0000) GS:ffff888125225000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3021aff8 CR3: 00000000431f4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 _ieee80211_link_use_channel+0x27a/0x7f0 net/mac80211/chan.c:2175
 ieee80211_link_use_channel net/mac80211/ieee80211_i.h:2786 [inline]
 ieee80211_set_monitor_channel+0x692/0x8e0 net/mac80211/cfg.c:1087
 rdev_set_monitor_channel net/wireless/rdev-ops.h:453 [inline]
 cfg80211_set_monitor_channel+0x22d/0x5f0 net/wireless/chan.c:1602
 cfg80211_wext_siwfreq+0x713/0x850 net/wireless/wext-compat.c:792
 ioctl_standard_call+0xcb/0x1b0 net/wireless/wext-core.c:1042
 wireless_process_ioctl net/wireless/wext-core.c:-1 [inline]
 wext_ioctl_dispatch+0xee/0x410 net/wireless/wext-core.c:1013
 wext_handle_ioctl+0x10f/0x1d0 net/wireless/wext-core.c:1074
 sock_ioctl+0x159/0x7f0 net/socket.c:1366
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f07e999c819
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:00007f07ea7c3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f07e9c15fa0 RCX: 00007f07e999c819
RDX: 00002000000000c0 RSI: 0000000000008b04 RDI: 000000000000000a
RBP: 00007f07e9a32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f07e9c16038 R14: 00007f07e9c15fa0 R15: 00007ffdfc834a38
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/21 19:47 bpf-next c8f0ee969f76 0b6ab7ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in cfg80211_chandef_dfs_required
2026/03/25 04:23 net-next b1c803d5c816 35e4ff71 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in cfg80211_chandef_dfs_required
* Struck through repros no longer work on HEAD.