syzbot


divide error in mac80211_hwsim_link_info_changed (2)

Status: upstream: reported on 2025/04/11 03:06
Subsystems: wireless
[Documentation on labels]
Reported-by: syzbot+5bb5f06f99924ea0cf86@syzkaller.appspotmail.com
First crash: 113d, last: 19d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [wireless?] divide error in mac80211_hwsim_link_info_changed (2) 0 (1) 2025/04/11 03:06
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream divide error in mac80211_hwsim_link_info_changed wireless 2 1 376d 375d 0/29 auto-obsoleted due to no activity on 2024/10/25 21:22

Sample crash report:
Oops: divide error: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 4157 Comm: kworker/u8:8 Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:mac80211_hwsim_link_info_changed+0x460/0xd80 drivers/net/wireless/virtual/mac80211_hwsim.c:2555
Code: c6 48 8b 7c 24 18 48 8b 5c 24 38 74 0a e8 e8 e5 2f fb 48 8b 7c 24 18 48 8b 0f 89 ce 4c 89 e0 48 c1 e8 20 74 5a 4c 89 e0 31 d2 <48> f7 f6 eb 57 e8 16 63 cc fa 48 8b 5c 24 18 48 8d 7b 10 e8 e8 8e
RSP: 0018:ffffc9000d927860 EFLAGS: 00010246
RAX: 00063984f4e09acd RBX: ffff88806cb0f048 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88806cb0f040
RBP: ffffc9000d927948 R08: ffffffff8fa1eff7 R09: 1ffffffff1f43dfe
R10: dffffc0000000000 R11: ffffffff8167a460 R12: 00063984f4e09acd
R13: ffff88806cb0efc8 R14: dffffc0000000000 R15: 0000000000000200
FS:  0000000000000000(0000) GS:ffff888125d1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000801f5018 CR3: 00000000687a2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 drv_link_info_changed+0x51b/0x870 net/mac80211/driver-ops.c:-1
 ieee80211_offchannel_return+0x375/0x500 net/mac80211/offchannel.c:160
 __ieee80211_roc_work+0x265/0x320 net/mac80211/offchannel.c:480
 cfg80211_wiphy_work+0x2df/0x460 net/wireless/core.c:435
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:mac80211_hwsim_link_info_changed+0x460/0xd80 drivers/net/wireless/virtual/mac80211_hwsim.c:2555
Code: c6 48 8b 7c 24 18 48 8b 5c 24 38 74 0a e8 e8 e5 2f fb 48 8b 7c 24 18 48 8b 0f 89 ce 4c 89 e0 48 c1 e8 20 74 5a 4c 89 e0 31 d2 <48> f7 f6 eb 57 e8 16 63 cc fa 48 8b 5c 24 18 48 8d 7b 10 e8 e8 8e
RSP: 0018:ffffc9000d927860 EFLAGS: 00010246
RAX: 00063984f4e09acd RBX: ffff88806cb0f048 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88806cb0f040
RBP: ffffc9000d927948 R08: ffffffff8fa1eff7 R09: 1ffffffff1f43dfe
R10: dffffc0000000000 R11: ffffffff8167a460 R12: 00063984f4e09acd
R13: ffff88806cb0efc8 R14: dffffc0000000000 R15: 0000000000000200
FS:  0000000000000000(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000080e80000 CR3: 000000005a4f6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000097 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	48 8b 7c 24 18       	mov    0x18(%rsp),%rdi
   5:	48 8b 5c 24 38       	mov    0x38(%rsp),%rbx
   a:	74 0a                	je     0x16
   c:	e8 e8 e5 2f fb       	call   0xfb2fe5f9
  11:	48 8b 7c 24 18       	mov    0x18(%rsp),%rdi
  16:	48 8b 0f             	mov    (%rdi),%rcx
  19:	89 ce                	mov    %ecx,%esi
  1b:	4c 89 e0             	mov    %r12,%rax
  1e:	48 c1 e8 20          	shr    $0x20,%rax
  22:	74 5a                	je     0x7e
  24:	4c 89 e0             	mov    %r12,%rax
  27:	31 d2                	xor    %edx,%edx
* 29:	48 f7 f6             	div    %rsi <-- trapping instruction
  2c:	eb 57                	jmp    0x85
  2e:	e8 16 63 cc fa       	call   0xfacc6349
  33:	48 8b 5c 24 18       	mov    0x18(%rsp),%rbx
  38:	48 8d 7b 10          	lea    0x10(%rbx),%rdi
  3c:	e8                   	.byte 0xe8
  3d:	e8                   	.byte 0xe8
  3e:	8e                   	.byte 0x8e

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/09 20:31 upstream 733923397fd9 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 divide error in mac80211_hwsim_link_info_changed
2025/04/07 02:59 upstream 16cd1c265776 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 divide error in mac80211_hwsim_link_info_changed
* Struck through repros no longer work on HEAD.