From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f207.google.com (mail-oi1-f207.google.com [209.85.167.207]) (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 057DF145A1F for ; Sun, 9 Aug 2026 23:44:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.207 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786319069; cv=none; b=T/cdYhSfS4074wp5fdw+s8RJDqLK7erpsBlbHMk536ovnf0DW1Vb7VIa5J9pjF99r37xm6Trgavajo9/9klBaabgATalv65on5k60VIbceqKDLrzUhordxh3o0s6HBV6rufBK02iYPC1+9QTDgKznZe2M79OIXoQB96Lf240sN0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786319069; c=relaxed/simple; bh=uQd/Qz8bkcT7WSFuT32E9AsaY6StteWzMLHWPKOi+EE=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=ssW1Y5ssNZcCh2ye4DX7gOXeFTkdFcc6xdAkf9kTsXNXzRjDN/s0p0yWSC4G+fHo/rz2EwNXtsJONGjGGSbsSVjv2k5ne3zDZELVQYffYRjKVrSbwsX2n4dDayHFudXqOx3JB/N53M7rfCr6u623KfrupSMIya+gLM3cUammAjo= 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=209.85.167.207 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-oi1-f207.google.com with SMTP id 5614622812f47-4afa222912eso953673b6e.2 for ; Sun, 09 Aug 2026 16:44:27 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786319067; x=1786923867; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=IsAz+s9PBiZETLOc7njAauA7t2vNPxnzL2teOHx2ORw=; b=mG9BTIpURL97yWo017kk+IjMjkRD4QD1r8EK4p4OkDIHOL77jWCXfUL0gOd3RR72bj 6OHxW6Qs//Y5NEPNuIKKueSvhXOo7OVOVgVpJLiHM78WkKyHg9dolQ0laz95MFVUGQyQ 1WizygQDu2OY+zFluaMx+pRGXrL/+nlGB/rhXepFRxSSkDFfxfPLGUOAIBuPirJz17Aj cgNnHVKt7bkhX7WlOhCmFEd4aHn7yR3lcejK6VUtYvztmTuj7Hhzy1nI7YcBawaVANxY +9xmNjJkcfa9YR3bz1GAwXKqkVKwXt1St87MxcvhVh8T5ydjJ44f8M+yuORa27JtOdlg B/ig== X-Forwarded-Encrypted: i=1; AHgh+Ro0/8CHnQ6YD2sAHOfdUiGwfudrwPW8NfXKnp3DDeu0jfWJE+rtuSEAqh1gvvdngtMl/rUVLMOrTKHKsls=@vger.kernel.org X-Gm-Message-State: AOJu0YxKpOQL/MJciy43GZmGvuNwEJQPWJbzVpUeIktB+/EUAydjiPu0 Eut3C8nUS/DjPH1ZI5kpSHcTCmqbtlvhkbmbJaLXxS892SFtCHpVzkkW1eQKNrhSVbLh4PHv4zk aG4dvjdbSGTwxqPnsab2YoWrzPADX3ftz7smMoapcJjKRgMtkdN/R+77CqwM= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:178b:b0:495:ce61:4e0c with SMTP id 5614622812f47-4b1ab72c113mr9027164b6e.3.1786319066859; Sun, 09 Aug 2026 16:44:26 -0700 (PDT) Date: Sun, 09 Aug 2026 16:44:26 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a7910da.9c11d2ce.289b96.00da.GAE@google.com> Subject: [syzbot] [iommu?] KASAN: slab-use-after-free Read in free_iova From: syzbot To: baolu.lu@linux.intel.com, dwmw2@infradead.org, iommu@lists.linux.dev, joro@8bytes.org, linux-kernel@vger.kernel.org, robin.murphy@arm.com, syzkaller-bugs@googlegroups.com, will@kernel.org Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 562bfb501c54 Merge tag 'integrity-v7.2-rc7' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17ba93b9580000 kernel config: https://syzkaller.appspot.com/x/.config?x=c05be6c9b0d36cb9 dashboard link: https://syzkaller.appspot.com/bug?extid=90c2d711b5218d10ce61 compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-562bfb50.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/7580e6506574/vmlinux-562bfb50.xz kernel image: https://storage.googleapis.com/syzbot-assets/883f7f234497/bzImage-562bfb50.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+90c2d711b5218d10ce61@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-use-after-free in private_find_iova drivers/iommu/iova.c:285 [inline] BUG: KASAN: slab-use-after-free in free_iova+0xab/0x200 drivers/iommu/iova.c:355 Read of size 8 at addr ffff888000274d60 by task syz.0.0/5327 CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 private_find_iova drivers/iommu/iova.c:285 [inline] free_iova+0xab/0x200 drivers/iommu/iova.c:355 fq_ring_free_locked+0x1ab/0x310 drivers/iommu/dma-iommu.c:155 fq_ring_free drivers/iommu/dma-iommu.c:170 [inline] fq_flush_timeout+0x234/0x2d0 drivers/iommu/dma-iommu.c:194 call_timer_fn+0x192/0x5e0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2374 [inline] __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386 run_timer_base kernel/time/timer.c:2395 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:console_flush_one_record arch/x86/include/asm/irqflags.h:-1 [inline] RIP: 0010:console_flush_all+0x7d2/0xaf0 kernel/printk/printk.c:3343 Code: ff ff e8 81 3b 21 00 90 0f 0b 90 e9 9c fc ff ff e8 73 3b 21 00 e8 ce 5d 2d 0a 48 85 db 74 c0 e8 64 3b 21 00 fb 48 8b 5c 24 18 <48> 8b 44 24 28 42 80 3c 20 00 4d 8d 77 58 74 08 4c 89 f7 e8 e6 6d RSP: 0018:ffffc9000f6271e0 EFLAGS: 00000283 RAX: ffffffff81a5e75c RBX: ffffc9000f627340 RCX: 0000000000100000 RDX: ffffc9000edfa000 RSI: 000000000002c5aa RDI: 000000000002c5ab RBP: ffffc9000f6272f0 R08: ffffffff9057c237 R09: 1ffffffff20af846 R10: dffffc0000000000 R11: fffffbfff20af847 R12: dffffc0000000000 R13: 0000000000000001 R14: 0000000000000000 R15: ffffffff8f471ce0 __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3413 vprintk_emit+0x485/0x560 kernel/printk/printk.c:2479 __warn_printf lib/bug.c:189 [inline] __report_bug+0x3c5/0x570 lib/bug.c:249 report_bug_entry+0x19a/0x290 lib/bug.c:274 handle_bug+0xce/0x200 arch/x86/kernel/traps.c:431 exc_invalid_op+0x1a/0x50 arch/x86/kernel/traps.c:490 asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:593 RIP: 0010:debug_print_object+0x18a/0x230 lib/debugobjects.c:629 Code: f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 3d 13 56 fd 4d 8b 0f 4c 89 ef 48 8b 74 24 08 48 89 ea 44 89 e1 4d 89 f0 ff 34 24 <67> 48 0f b9 3a 48 83 c4 08 ff 05 03 b3 77 0b 48 83 c4 10 5b 41 5c RSP: 0018:ffffc9000f6276f0 EFLAGS: 00010246 RAX: 1ffffffff17decd0 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffffffff8c4bf940 RSI: ffffffff8c4bf3c0 RDI: ffffffff90632440 RBP: ffffffff8c4bf940 R08: ffff8880002684e0 R09: ffffffff8bef79e0 R10: dffffc0000000000 R11: ffffffff81b33db0 R12: 0000000000000000 R13: ffffffff90632440 R14: ffff8880002684e0 R15: ffffffff8bef6680 __debug_check_no_obj_freed lib/debugobjects.c:1171 [inline] debug_check_no_obj_freed+0x2e3/0x450 lib/debugobjects.c:1201 slab_free_hook mm/slub.c:2608 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x13e/0x640 mm/slub.c:6692 iommu_domain_free drivers/iommu/iommu.c:2131 [inline] iommu_deinit_device+0x401/0x840 drivers/iommu/iommu.c:600 __iommu_group_remove_device+0x1dd/0x270 drivers/iommu/iommu.c:764 iommu_release_device drivers/iommu/iommu.c:783 [inline] iommu_bus_notifier+0x6d/0x2c0 drivers/iommu/iommu.c:1826 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380 bus_notify+0x143/0x180 drivers/base/bus.c:1086 device_del+0x740/0x8f0 drivers/base/core.c:3978 pci_destroy_dev drivers/pci/remove.c:46 [inline] pci_remove_bus_device+0x12a/0x2a0 drivers/pci/remove.c:110 pci_stop_and_remove_bus_device drivers/pci/remove.c:129 [inline] pci_stop_and_remove_bus_device_locked+0x7f/0xb0 drivers/pci/remove.c:136 remove_store+0xe5/0x150 drivers/pci/pci-sysfs.c:523 kernfs_fop_write_iter+0x3a4/0x540 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2afa79e019 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2afb6f9fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f2afaa25fa0 RCX: 00007f2afa79e019 RDX: 0000000000000001 RSI: 00002000000000c0 RDI: 0000000000000008 RBP: 00007f2afa83500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2afaa26038 R14: 00007f2afaa25fa0 R15: 00007fff4eb947c8 Allocated by task 1: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4931 alloc_iova_mem drivers/iommu/iova.c:231 [inline] alloc_and_init_iova drivers/iommu/iova.c:474 [inline] __insert_new_range drivers/iommu/iova.c:489 [inline] reserve_iova+0x2b0/0x480 drivers/iommu/iova.c:544 iova_reserve_pci_windows drivers/iommu/dma-iommu.c:521 [inline] iova_reserve_iommu_regions drivers/iommu/dma-iommu.c:563 [inline] iommu_dma_init_domain drivers/iommu/dma-iommu.c:723 [inline] iommu_setup_dma_ops+0xa21/0x1820 drivers/iommu/dma-iommu.c:2159 bus_iommu_probe+0x296/0x470 drivers/iommu/iommu.c:1983 iommu_device_register+0x1af/0x210 drivers/iommu/iommu.c:307 intel_iommu_init+0x6f0/0x8e0 drivers/iommu/intel/iommu.c:2662 pci_iommu_init+0x38/0x70 arch/x86/kernel/pci-dma.c:174 do_one_initcall+0x250/0x870 init/main.c:1347 do_initcall_level+0x10a/0x1a0 init/main.c:1409 do_initcalls+0x59/0xa0 init/main.c:1425 kernel_init_freeable+0x29d/0x3e0 init/main.c:1658 kernel_init+0x1d/0x1d0 init/main.c:1548 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 5327: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kmem_cache_free+0x182/0x650 mm/slub.c:6504 free_iova_mem drivers/iommu/iova.c:237 [inline] put_iova_domain+0xcc/0x100 drivers/iommu/iova.c:454 iommu_put_dma_cookie+0x45c/0x560 drivers/iommu/dma-iommu.c:431 iommu_domain_free drivers/iommu/iommu.c:2131 [inline] iommu_deinit_device+0x401/0x840 drivers/iommu/iommu.c:600 __iommu_group_remove_device+0x1dd/0x270 drivers/iommu/iommu.c:764 iommu_release_device drivers/iommu/iommu.c:783 [inline] iommu_bus_notifier+0x6d/0x2c0 drivers/iommu/iommu.c:1826 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380 bus_notify+0x143/0x180 drivers/base/bus.c:1086 device_del+0x740/0x8f0 drivers/base/core.c:3978 pci_destroy_dev drivers/pci/remove.c:46 [inline] pci_remove_bus_device+0x12a/0x2a0 drivers/pci/remove.c:110 pci_stop_and_remove_bus_device drivers/pci/remove.c:129 [inline] pci_stop_and_remove_bus_device_locked+0x7f/0xb0 drivers/pci/remove.c:136 remove_store+0xe5/0x150 drivers/pci/pci-sysfs.c:523 kernfs_fop_write_iter+0x3a4/0x540 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888000274d40 which belongs to the cache iommu_iova of size 40 The buggy address is located 32 bytes inside of freed 40-byte region [ffff888000274d40, ffff888000274d68) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x274 flags: 0x7ff00000000000(node=0|zone=0|lastcpupid=0x7ff) page_type: f5(slab) raw: 007ff00000000000 ffff888030463500 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800400040 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 8498569964, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab+0x79/0x5e0 mm/slub.c:3380 new_slab mm/slub.c:3426 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] kmem_cache_alloc_noprof+0x382/0x5f0 mm/slub.c:4931 alloc_iova_mem drivers/iommu/iova.c:231 [inline] alloc_and_init_iova drivers/iommu/iova.c:474 [inline] __insert_new_range drivers/iommu/iova.c:489 [inline] reserve_iova+0x2b0/0x480 drivers/iommu/iova.c:544 iova_reserve_pci_windows drivers/iommu/dma-iommu.c:521 [inline] iova_reserve_iommu_regions drivers/iommu/dma-iommu.c:563 [inline] iommu_dma_init_domain drivers/iommu/dma-iommu.c:723 [inline] iommu_setup_dma_ops+0xa21/0x1820 drivers/iommu/dma-iommu.c:2159 bus_iommu_probe+0x296/0x470 drivers/iommu/iommu.c:1983 iommu_device_register+0x1af/0x210 drivers/iommu/iommu.c:307 intel_iommu_init+0x6f0/0x8e0 drivers/iommu/intel/iommu.c:2662 pci_iommu_init+0x38/0x70 arch/x86/kernel/pci-dma.c:174 do_one_initcall+0x250/0x870 init/main.c:1347 do_initcall_level+0x10a/0x1a0 init/main.c:1409 do_initcalls+0x59/0xa0 init/main.c:1425 page_owner free stack trace missing Memory state around the buggy address: ffff888000274c00: 00 00 00 00 00 fc fc fc 00 00 00 00 00 fc fc fc ffff888000274c80: fa fb fb fb fb fc fc fc fa fb fb fb fb fc fc fc >ffff888000274d00: fa fb fb fb fb fc fc fc fa fb fb fb fb fc fc fc ^ ffff888000274d80: fa fb fb fb fb fc fc fc 00 00 00 00 00 fc fc fc ffff888000274e00: 00 00 00 00 00 fc fc fc 00 00 00 00 00 fc fc fc ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: ff ljmp (bad) 1: e8 81 3b 21 00 call 0x213b87 6: 90 nop 7: 0f 0b ud2 9: 90 nop a: e9 9c fc ff ff jmp 0xfffffcab f: e8 73 3b 21 00 call 0x213b87 14: e8 ce 5d 2d 0a call 0xa2d5de7 19: 48 85 db test %rbx,%rbx 1c: 74 c0 je 0xffffffde 1e: e8 64 3b 21 00 call 0x213b87 23: fb sti 24: 48 8b 5c 24 18 mov 0x18(%rsp),%rbx * 29: 48 8b 44 24 28 mov 0x28(%rsp),%rax <-- trapping instruction 2e: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) 33: 4d 8d 77 58 lea 0x58(%r15),%r14 37: 74 08 je 0x41 39: 4c 89 f7 mov %r14,%rdi 3c: e8 .byte 0xe8 3d: e6 6d out %al,$0x6d --- 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