From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f206.google.com (mail-il1-f206.google.com [209.85.166.206]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BDF5B2E6D08 for ; Tue, 8 Jul 2025 17:52:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.206 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751997150; cv=none; b=ctS7+5GQyOMtGnB7KGTVCdNcDFy0T0rjfe98VRX7nC3DFgb2PnkJc/Lk8wpSaW3YMDFkzOc6QL5waKpjI0Zd3iPFwXYzS8E+RtrjhXut+kybn9G8WepqPSB1IwB6w2+ajZ+M11+p7Cn/iZhhI2jrro2JUQFXkqCcARjM7wCGRc4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751997150; c=relaxed/simple; bh=raqfKm1Ddhkys2uymzfmJ5mW14IHvpYEkzirh2O/1QY=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=JdDTLSbZ2cQOuBELg/MbucfuAz/F1h0xweBxwEXsMywV+pZtIVoQ49n3lisGhPY62Inl1WTEkHHmHgloEfvtflSwBqqbQATtIYMPjUHiXL0wagwQxxzSzJlINqcelUPOAmwHkQzFHj4agXKTkrLwRyvU2bxW2ESXFpRouUM6S9M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.206 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-il1-f206.google.com with SMTP id e9e14a558f8ab-3ddd5cd020dso104607185ab.0 for ; Tue, 08 Jul 2025 10:52:28 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751997148; x=1752601948; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=Ny6or7BKp9ehynMnqSKdVfi1cxR+4gT3nWksYBIqyNo=; b=qNMIG3X5FdTF7jnnnjAn3wfL7CLSIkk/9jQdbQtcXyehx5mv4ZhjNTI7xTHZY5yVHh brFn8OnyAnXVG6fMKAGCVla5bvEV9POkP1grsgrNwRcAVE0dMMY97vo255uMWcUNzsap cl8SFHUhQupSHoO+Z70yhdFA9hVjFTKVQustR2luXNt7h++fPRT93CzcdE1rbboLylOr hWymtdEIEdutiJfcKV63kEyRxRCru9TzoIlEnfouNkM5QDQL/kmNAzk659/bWNXZo8SK ZuTTuaUMTv/d67gGBiYgIWLdRno4T5uKAq0++b7DCbLYarIf0hV8SFw4fqjdq04tTteC 5xlQ== X-Forwarded-Encrypted: i=1; AJvYcCW/ByJJKJ664bCOUE0eEfmSTNEBZ7PW1Y8WdFuUXiuMIxu1fGTytqW4jrw6MFrinY/D7RyAcZal2Nkhh+I=@vger.kernel.org X-Gm-Message-State: AOJu0YyyWno1r7FR5eF4LiQQu6W4wu80BfQAHO/wAA5adrtiH2UZtRcu kMhj/Yioy6FuS1irP0mgeag5qd1RnZ/yJawYlAW15Cv6A1wSm2HpvRCz7yFLTM/IgBEKRLtJFSw b3fP5lPDS2Rfv0JAKZdV/KoIjBgQPvPQE+QEzT5HBn/00GAWOU1YOeG/1edE= X-Google-Smtp-Source: AGHT+IEJMOFc+Tzu3aAKQYVyDD//jl/FNtdHH7hxJxOxuUhrp1eglGzrhLPjCvjahKddZpuDYIQMFy3NSLGAugdYxo1TkXWuNfcQ Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:1527:b0:3e0:4f66:310a with SMTP id e9e14a558f8ab-3e1355a8e41mr169189265ab.16.1751997147727; Tue, 08 Jul 2025 10:52:27 -0700 (PDT) Date: Tue, 08 Jul 2025 10:52:27 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <686d5adb.050a0220.1ffab7.001a.GAE@google.com> Subject: [syzbot] [kernel?] divide error in comedi_inc_scan_progress From: syzbot To: abbotti@mev.co.uk, hsweeten@visionengravers.com, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: d7b8f8e20813 Linux 6.16-rc5 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1250d28c580000 kernel config: https://syzkaller.appspot.com/x/.config?x=f51185bd4f40ad44 dashboard link: https://syzkaller.appspot.com/bug?extid=af53dea94b16396bc646 compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/f933e0e4a6c5/disk-d7b8f8e2.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/a82be954c91b/vmlinux-d7b8f8e2.xz kernel image: https://storage.googleapis.com/syzbot-assets/66dbc3de1264/bzImage-d7b8f8e2.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+af53dea94b16396bc646@syzkaller.appspotmail.com Oops: divide error: 0000 [#1] SMP KASAN NOPTI CPU: 0 UID: 0 PID: 9896 Comm: syz.3.1000 Not tainted 6.16.0-rc5-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:comedi_inc_scan_progress+0x1cc/0x340 drivers/comedi/drivers.c:556 Code: 00 00 00 03 43 2c 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 0f b6 14 11 84 d2 74 09 80 fa 03 0f 8e 53 01 00 00 31 d2 b3 80 00 00 00 89 53 2c e8 a6 76 cd f8 48 8d 7b 34 48 b8 00 00 RSP: 0018:ffffc90000007da0 EFLAGS: 00010046 RAX: 0000000000000001 RBX: ffff88807af3e400 RCX: 1ffff1100f5e7c90 RDX: 0000000000000000 RSI: ffffffff88ee6f98 RDI: ffff88807af3e480 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000002 R15: 0000000010000000 FS: 00007f7abf9b16c0(0000) GS:ffff888124718000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000084030 CR3: 00000000317d4000 CR4: 00000000003526f0 Call Trace: comedi_buf_write_samples+0x406/0x640 drivers/comedi/comedi_buf.c:603 aio_iiro_16_cos+0x132/0x160 drivers/comedi/drivers/aio_iiro_16.c:69 __handle_irq_event_percpu+0x22c/0x7d0 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x28e/0xab0 kernel/irq/chip.c:797 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:254 [inline] call_irq_handler arch/x86/kernel/irq.c:266 [inline] __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:292 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:285 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0xd7b/0x1510 kernel/smp.c:885 Code: e8 6a 19 0c 00 45 85 ed 74 46 48 8b 14 24 49 89 d6 49 89 d5 49 c1 ee 03 41 83 e5 07 4d 01 e6 41 83 c5 03 e8 07 1e 0c 00 f3 90 <41> 0f b6 06 41 38 c5 7c 08 84 c0 0f 85 6f 05 00 00 8b 43 08 31 ff RSP: 0018:ffffc9000214f2b8 EFLAGS: 00000246 RAX: 0000000000080000 RBX: ffff8880b853fe20 RCX: ffffc9000f741000 RDX: 0000000000080000 RSI: ffffffff81afc8a9 RDI: 0000000000000005 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: dffffc0000000000 R13: 0000000000000003 R14: ffffed10170a7fc5 R15: ffff8880b843b580 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline] flush_tlb_mm_range+0x4a0/0x1790 arch/x86/mm/tlb.c:1451 flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline] ptep_clear_flush+0x136/0x180 mm/pgtable-generic.c:101 wp_page_copy mm/memory.c:3635 [inline] do_wp_page+0x1683/0x4f20 mm/memory.c:4030 handle_pte_fault mm/memory.c:6085 [inline] __handle_mm_fault+0x2223/0x5490 mm/memory.c:6212 handle_mm_fault+0x589/0xd10 mm/memory.c:6381 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:__put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:104 Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca e9 c1 5a 03 00 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc9000214f9f8 EFLAGS: 00050246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000200000084030 RDX: 0000000000080000 RSI: ffffffff89561a63 RDI: 0000000000000005 RBP: ffffc9000214fd98 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000001 R12: 0000000000000000 R13: 0000200000084000 R14: ffffc9000214fddc R15: 0000000000000002 ____sys_recvmsg+0x2ee/0x6b0 net/socket.c:2799 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2828 do_recvmmsg+0x2fe/0x750 net/socket.c:2923 __sys_recvmmsg net/socket.c:2997 [inline] __do_sys_recvmmsg net/socket.c:3020 [inline] __se_sys_recvmmsg net/socket.c:3013 [inline] __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3013 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7abeb8e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7abf9b1038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f7abedb6160 RCX: 00007f7abeb8e929 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000008 RBP: 00007f7abec10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f7abedb6160 R15: 00007fff425d3008 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:comedi_inc_scan_progress+0x1cc/0x340 drivers/comedi/drivers.c:556 Code: 00 00 00 03 43 2c 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 0f b6 14 11 84 d2 74 09 80 fa 03 0f 8e 53 01 00 00 31 d2 b3 80 00 00 00 89 53 2c e8 a6 76 cd f8 48 8d 7b 34 48 b8 00 00 RSP: 0018:ffffc90000007da0 EFLAGS: 00010046 RAX: 0000000000000001 RBX: ffff88807af3e400 RCX: 1ffff1100f5e7c90 RDX: 0000000000000000 RSI: ffffffff88ee6f98 RDI: ffff88807af3e480 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000002 R15: 0000000010000000 FS: 00007f7abf9b16c0(0000) GS:ffff888124718000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000084030 CR3: 00000000317d4000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 00 00 add %al,(%rax) 2: 03 43 2c add 0x2c(%rbx),%eax 5: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx c: fc ff df f: 48 89 f9 mov %rdi,%rcx 12: 48 c1 e9 03 shr $0x3,%rcx 16: 0f b6 14 11 movzbl (%rcx,%rdx,1),%edx 1a: 84 d2 test %dl,%dl 1c: 74 09 je 0x27 1e: 80 fa 03 cmp $0x3,%dl 21: 0f 8e 53 01 00 00 jle 0x17a 27: 31 d2 xor %edx,%edx * 29: f7 b3 80 00 00 00 divl 0x80(%rbx) <-- trapping instruction 2f: 89 53 2c mov %edx,0x2c(%rbx) 32: e8 a6 76 cd f8 call 0xf8cd76dd 37: 48 8d 7b 34 lea 0x34(%rbx),%rdi 3b: 48 rex.W 3c: b8 .byte 0xb8 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup