syzbot


divide error in mac80211_hwsim_link_info_changed

Status: upstream: reported on 2024/07/18 08:46
Subsystems: wireless
[Documentation on labels]
Reported-by: syzbot+c6f3c081bf956c97e4de@syzkaller.appspotmail.com
First crash: 52d, last: 52d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [wireless?] divide error in mac80211_hwsim_link_info_changed 0 (1) 2024/07/18 08:46

Sample crash report:
Oops: divide error: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 PID: 11 Comm: kworker/u8:0 Not tainted 6.10.0-syzkaller-04472-g51835949dda3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: events_unbound cfg80211_wiphy_work

RIP: 0010:mac80211_hwsim_link_info_changed+0x409/0xf00 drivers/net/wireless/virtual/mac80211_hwsim.c:2547
Code: 00 fc ff df 43 80 7c 3d 00 00 48 8b 44 24 20 74 0f 48 8b 7c 24 20 e8 a6 ff 0d fb 48 8b 44 24 20 48 8b 08 89 ce 48 89 d8 31 d2 <48> f7 f6 29 d1 48 69 f1 e8 03 00 00 4c 89 f7 31 d2 b9 05 00 00 00
RSP: 0018:ffffc900001077a0 EFLAGS: 00010246

RAX: 00061d780b08a1f3 RBX: 00061d780b08a1f3 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000040
RBP: ffffc90000107890 R08: ffffffff8183f431 R09: 1ffffffff25f9ec5
R10: dffffc0000000000 R11: ffffffff813597f0 R12: 0000000000000200
R13: 1ffff1100c778e08 R14: ffff888063bc7048 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c34d35b CR3: 000000006a936000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 drv_link_info_changed+0x53d/0x8b0
 ieee80211_offchannel_return+0x3a4/0x530 net/mac80211/offchannel.c:160
 __ieee80211_scan_completed+0x77f/0xb60 net/mac80211/scan.c:495
 ieee80211_scan_work+0x1cc/0x1da0 net/mac80211/scan.c:1162
 cfg80211_wiphy_work+0x2db/0x490 net/wireless/core.c:440
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:mac80211_hwsim_link_info_changed+0x409/0xf00 drivers/net/wireless/virtual/mac80211_hwsim.c:2547
Code: 00 fc ff df 43 80 7c 3d 00 00 48 8b 44 24 20 74 0f 48 8b 7c 24 20 e8 a6 ff 0d fb 48 8b 44 24 20 48 8b 08 89 ce 48 89 d8 31 d2 <48> f7 f6 29 d1 48 69 f1 e8 03 00 00 4c 89 f7 31 d2 b9 05 00 00 00
RSP: 0018:ffffc900001077a0 EFLAGS: 00010246
RAX: 00061d780b08a1f3 RBX: 00061d780b08a1f3 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000040
RBP: ffffc90000107890 R08: ffffffff8183f431 R09: 1ffffffff25f9ec5
R10: dffffc0000000000 R11: ffffffff813597f0 R12: 0000000000000200
R13: 1ffff1100c778e08 R14: ffff888063bc7048 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f37c5e6dfc8 CR3: 000000001f47a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 3 bytes skipped:
   0:	df 43 80             	filds  -0x80(%rbx)
   3:	7c 3d                	jl     0x42
   5:	00 00                	add    %al,(%rax)
   7:	48 8b 44 24 20       	mov    0x20(%rsp),%rax
   c:	74 0f                	je     0x1d
   e:	48 8b 7c 24 20       	mov    0x20(%rsp),%rdi
  13:	e8 a6 ff 0d fb       	call   0xfb0dffbe
  18:	48 8b 44 24 20       	mov    0x20(%rsp),%rax
  1d:	48 8b 08             	mov    (%rax),%rcx
  20:	89 ce                	mov    %ecx,%esi
  22:	48 89 d8             	mov    %rbx,%rax
  25:	31 d2                	xor    %edx,%edx
* 27:	48 f7 f6             	div    %rsi <-- trapping instruction
  2a:	29 d1                	sub    %edx,%ecx
  2c:	48 69 f1 e8 03 00 00 	imul   $0x3e8,%rcx,%rsi
  33:	4c 89 f7             	mov    %r14,%rdi
  36:	31 d2                	xor    %edx,%edx
  38:	b9 05 00 00 00       	mov    $0x5,%ecx

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/17 21:21 net-next 51835949dda3 03114f55 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce divide error in mac80211_hwsim_link_info_changed
* Struck through repros no longer work on HEAD.