syzbot


divide error in mac80211_hwsim_bss_info_changed (2)

Status: upstream: reported on 2023/02/27 09:41
Reported-by: syzbot+d94079e139328aacb542@syzkaller.appspotmail.com
First crash: 649d, last: 649d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 divide error in mac80211_hwsim_bss_info_changed 3 58d 148d 0/3 upstream: reported on 2024/07/12 08:51
android-54 divide error in mac80211_hwsim_bss_info_changed 2 1517d 1524d 0/2 auto-closed as invalid on 2021/02/09 23:56
upstream divide error in mac80211_hwsim_bss_info_changed (2) wireless 2 1098d 1146d 0/28 auto-closed as invalid on 2022/04/04 22:30
upstream divide error in mac80211_hwsim_bss_info_changed wireless 1 1334d 1300d 0/28 auto-closed as invalid on 2021/08/12 01:33
linux-4.19 divide error in mac80211_hwsim_bss_info_changed 1 780d 780d 0/1 auto-obsoleted due to no activity on 2023/02/16 17:15

Sample crash report:
device bond4 left promiscuous mode
device batadv3 left promiscuous mode
device bond5 left promiscuous mode
device batadv4 left promiscuous mode
divide error: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 3572 Comm: kworker/u4:5 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023
Workqueue: phy2 ieee80211_roc_work
RIP: 0010:mac80211_hwsim_bss_info_changed+0xd4b/0xf20 drivers/net/wireless/mac80211_hwsim.c:1781
Code: 48 ba 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 11 00 0f 85 96 01 00 00 49 8b b6 90 12 00 00 49 8d be 20 13 00 00 31 d2 89 f1 <48> f7 f1 29 d6 b9 01 00 00 00 31 d2 48 69 f6 e8 03 00 00 e8 9d 60
RSP: 0018:ffff8880a8f87bb0 EFLAGS: 00010246
RAX: 0005f5ab47967af6 RBX: 0000000000000200 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88805eba4500
RBP: ffff88805e79f180 R08: ffffffff8c665058 R09: 000000000001f638
R10: 0000000000000004 R11: ffffffff8c66505b R12: ffff88805eba18c0
R13: ffff88805eba4470 R14: ffff88805eba31e0 R15: ffff88805eba31e0
FS:  0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f94dc672d38 CR3: 000000009739d000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 drv_bss_info_changed net/mac80211/driver-ops.h:178 [inline]
 ieee80211_bss_info_change_notify+0x311/0x920 net/mac80211/main.c:204
 ieee80211_offchannel_return+0x37e/0x540 net/mac80211/offchannel.c:180
 __ieee80211_roc_work+0x345/0x3b0 net/mac80211/offchannel.c:462
 ieee80211_roc_work+0x2b/0x40 net/mac80211/offchannel.c:476
 process_one_work+0x864/0x1570 kernel/workqueue.c:2153
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Modules linked in:
audit: type=1800 audit(1677490872.816:31121): pid=28685 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="bus" dev="sda1" ino=14747 res=0
audit: type=1800 audit(1677490873.047:31122): pid=28724 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.0" name="bus" dev="sda1" ino=14802 res=0
---[ end trace b7a3e5f26ee6fe37 ]---
RIP: 0010:mac80211_hwsim_bss_info_changed+0xd4b/0xf20 drivers/net/wireless/mac80211_hwsim.c:1781
Code: 48 ba 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 11 00 0f 85 96 01 00 00 49 8b b6 90 12 00 00 49 8d be 20 13 00 00 31 d2 89 f1 <48> f7 f1 29 d6 b9 01 00 00 00 31 d2 48 69 f6 e8 03 00 00 e8 9d 60
RSP: 0018:ffff8880a8f87bb0 EFLAGS: 00010246
RAX: 0005f5ab47967af6 RBX: 0000000000000200 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88805eba4500
RBP: ffff88805e79f180 R08: ffffffff8c665058 R09: 000000000001f638
R10: 0000000000000004 R11: ffffffff8c66505b R12: ffff88805eba18c0
R13: ffff88805eba4470 R14: ffff88805eba31e0 R15: ffff88805eba31e0
FS:  0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdced551558 CR3: 000000009739d000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
   7:	fc ff df
   a:	48 c1 e9 03          	shr    $0x3,%rcx
   e:	80 3c 11 00          	cmpb   $0x0,(%rcx,%rdx,1)
  12:	0f 85 96 01 00 00    	jne    0x1ae
  18:	49 8b b6 90 12 00 00 	mov    0x1290(%r14),%rsi
  1f:	49 8d be 20 13 00 00 	lea    0x1320(%r14),%rdi
  26:	31 d2                	xor    %edx,%edx
  28:	89 f1                	mov    %esi,%ecx
* 2a:	48 f7 f1             	div    %rcx <-- trapping instruction
  2d:	29 d6                	sub    %edx,%esi
  2f:	b9 01 00 00 00       	mov    $0x1,%ecx
  34:	31 d2                	xor    %edx,%edx
  36:	48 69 f6 e8 03 00 00 	imul   $0x3e8,%rsi,%rsi
  3d:	e8                   	.byte 0xe8
  3e:	9d                   	popfq
  3f:	60                   	(bad)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/27 09:41 linux-4.19.y 3f8a27f9e27b 9189cb53 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 divide error in mac80211_hwsim_bss_info_changed
* Struck through repros no longer work on HEAD.