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: 261d, last: 35d
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] mac80211_hwsim: fix divide error in mac80211_hwsim_link_info_changed 7 (7) 2025/12/10 18:56
[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 524d 524d 0/29 auto-obsoleted due to no activity on 2024/10/25 21:22

Sample crash report:
Oops: divide error: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 11318 Comm: kworker/u8:61 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:mac80211_hwsim_link_info_changed+0xa1e/0xdc0 drivers/net/wireless/virtual/mac80211_hwsim.c:2598
Code: 80 3c 11 00 0f 85 60 03 00 00 48 8b 4c 24 10 4c 89 ef 48 8d 14 89 48 8b 0c 24 48 c1 e2 04 48 8b b4 11 b0 3f 00 00 31 d2 89 f1 <48> f7 f1 b9 05 00 00 00 29 d6 31 d2 48 69 f6 e8 03 00 00 e8 8a 4f
RSP: 0018:ffffc900160678d8 EFLAGS: 00010246
RAX: 00000000951a7ef6 RBX: 0000000000000200 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88807c4270b8
RBP: ffff888055572ad8 R08: 0000000000000004 R09: 0000000000078018
R10: 0000000000078018 R11: 0000000000000001 R12: ffff88807c420e80
R13: ffff88807c4270b8 R14: 1ffff92002c0cf20 R15: ffff88807c4270b0
FS:  0000000000000000(0000) GS:ffff888124a05000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fd1aff8 CR3: 000000007295e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 drv_link_info_changed+0x3ff/0x870 net/mac80211/driver-ops.c:491
 ieee80211_link_info_change_notify+0x202/0x3f0 net/mac80211/main.c:428
 ieee80211_offchannel_return+0x380/0x570 net/mac80211/offchannel.c:160
 __ieee80211_scan_completed+0x9ab/0xe40 net/mac80211/scan.c:510
 ieee80211_scan_work+0x3f1/0x2080 net/mac80211/scan.c:1184
 cfg80211_wiphy_work+0x2c7/0x580 net/wireless/core.c:435
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263
 process_scheduled_works kernel/workqueue.c:3346 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
 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+0xa1e/0xdc0 drivers/net/wireless/virtual/mac80211_hwsim.c:2598
Code: 80 3c 11 00 0f 85 60 03 00 00 48 8b 4c 24 10 4c 89 ef 48 8d 14 89 48 8b 0c 24 48 c1 e2 04 48 8b b4 11 b0 3f 00 00 31 d2 89 f1 <48> f7 f1 b9 05 00 00 00 29 d6 31 d2 48 69 f6 e8 03 00 00 e8 8a 4f
RSP: 0018:ffffc900160678d8 EFLAGS: 00010246
RAX: 00000000951a7ef6 RBX: 0000000000000200 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88807c4270b8
RBP: ffff888055572ad8 R08: 0000000000000004 R09: 0000000000078018
R10: 0000000000078018 R11: 0000000000000001 R12: ffff88807c420e80
R13: ffff88807c4270b8 R14: 1ffff92002c0cf20 R15: ffff88807c4270b0
FS:  0000000000000000(0000) GS:ffff888124a05000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8d561b42f8 CR3: 00000000b24a5000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
----------------
Code disassembly (best guess):
   0:	80 3c 11 00          	cmpb   $0x0,(%rcx,%rdx,1)
   4:	0f 85 60 03 00 00    	jne    0x36a
   a:	48 8b 4c 24 10       	mov    0x10(%rsp),%rcx
   f:	4c 89 ef             	mov    %r13,%rdi
  12:	48 8d 14 89          	lea    (%rcx,%rcx,4),%rdx
  16:	48 8b 0c 24          	mov    (%rsp),%rcx
  1a:	48 c1 e2 04          	shl    $0x4,%rdx
  1e:	48 8b b4 11 b0 3f 00 	mov    0x3fb0(%rcx,%rdx,1),%rsi
  25:	00
  26:	31 d2                	xor    %edx,%edx
  28:	89 f1                	mov    %esi,%ecx
* 2a:	48 f7 f1             	div    %rcx <-- trapping instruction
  2d:	b9 05 00 00 00       	mov    $0x5,%ecx
  32:	29 d6                	sub    %edx,%esi
  34:	31 d2                	xor    %edx,%edx
  36:	48 69 f6 e8 03 00 00 	imul   $0x3e8,%rsi,%rsi
  3d:	e8                   	.byte 0xe8
  3e:	8a                   	.byte 0x8a
  3f:	4f                   	rex.WRXB

Crashes (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/19 14:53 upstream 8b690556d8fe 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in mac80211_hwsim_link_info_changed
2025/11/18 09:31 upstream e7c375b18160 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce divide error in mac80211_hwsim_link_info_changed
2025/09/04 00:15 upstream ec299e4dc21e 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 divide error in mac80211_hwsim_link_info_changed
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
2025/11/19 09:54 upstream 8b690556d8fe 82d7b894 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream divide error in mac80211_hwsim_link_info_changed
2025/11/19 08:31 upstream 8b690556d8fe ef766cd7 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream divide error in mac80211_hwsim_link_info_changed
2025/11/18 18:58 upstream 5bebe8de1926 ef766cd7 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream divide error in mac80211_hwsim_link_info_changed
2025/09/04 04:10 upstream b9a10f876409 d291dd2d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 divide error in mac80211_hwsim_link_info_changed
2025/09/23 05:42 net 3491bb7dae5c 0ac7291c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce divide error in mac80211_hwsim_link_info_changed
2025/08/25 19:58 net-next 992e9f53a0db bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce divide error in mac80211_hwsim_link_info_changed
2025/08/10 08:30 linux-next b1549501188c 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root divide error in mac80211_hwsim_link_info_changed
* Struck through repros no longer work on HEAD.