Extracting prog: 3m30.687608752s Minimizing prog: 30m1.953522218s Simplifying prog options: 14m1.779648104s Extracting C: 4m35.660069692s Simplifying C: 0s extracting reproducer from 1 programs testing a last program of every proc single: executing 1 programs separately with timeout 30s testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000540)=ANY=[@ANYBLOB="043e1f0a"], 0x22) syz_emit_vhci(0x0, 0x0) syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program did not crash single: failed to extract reproducer single: executing 1 programs separately with timeout 6m0s testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000540)=ANY=[@ANYBLOB="043e1f0a"], 0x22) syz_emit_vhci(0x0, 0x0) syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program crashed: WARNING in hci_conn_timeout single: successfully extracted reproducer found reproducer with 3 syscalls minimizing guilty program testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000540)=ANY=[@ANYBLOB="043e1f0a"], 0x22) syz_emit_vhci(0x0, 0x0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000540)=ANY=[@ANYBLOB="043e1f0a"], 0x22) syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program crashed: WARNING in hci_conn_timeout testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(0x0, 0x22) syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000540)=ANY=[@ANYBLOB], 0x22) syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program did not crash extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci program crashed: no output from test machine a never seen crash title: no output from test machine, ignore simplifying guilty program options testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000540)=ANY=[@ANYBLOB="043e1f0a"], 0x22) syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000540)=ANY=[@ANYBLOB="043e1f0a"], 0x22) syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program crashed: WARNING in hci_conn_timeout extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000540)=ANY=[@ANYBLOB="043e1f0a"], 0x22) syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program crashed: INFO: task hung in hci_cmd_sync_clear validation run: crashed=true testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000540)=ANY=[@ANYBLOB="043e1f0a"], 0x22) syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program crashed: WARNING in hci_conn_timeout validation run: crashed=true testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci-syz_emit_vhci detailed listing: executing program 0: syz_emit_vhci(&(0x7f0000000540)=ANY=[@ANYBLOB="043e1f0a"], 0x22) syz_emit_vhci(&(0x7f0000000080)=@HCI_EVENT_PKT={0x4, @hci_ev_encrypt_change={{0x8, 0x4}, {0x40}}}, 0x7) program crashed: WARNING in hci_conn_timeout validation run: crashed=true reproducing took 1h7m29.609524651s repro crashed as (corrupted=false): ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 kobject: kobject_add_internal failed for hci1:0 with -EEXIST, don't try to register things with the same name in the same directory. Bluetooth: hci1: failed to register connection device ------------[ cut here ]------------ refcnt < 0 WARNING: net/bluetooth/hci_conn.c:567 at hci_conn_timeout+0xff/0x2c0 net/bluetooth/hci_conn.c:567, CPU#1: kworker/u9:1/5114 Modules linked in: CPU: 1 UID: 0 PID: 5114 Comm: kworker/u9:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026 Workqueue: hci1 hci_conn_timeout RIP: 0010:hci_conn_timeout+0xff/0x2c0 net/bluetooth/hci_conn.c:567 Code: 48 89 df e8 f3 99 09 00 eb 07 e8 6c b7 ae f7 b0 13 0f b6 f0 48 89 df 5b 41 5c 41 5e 41 5f 5d e9 07 a9 fe ff e8 52 b7 ae f7 90 <0f> 0b 90 eb 8c 44 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 31 ff ff ff RSP: 0018:ffffc90011077ad0 EFLAGS: 00010293 RAX: ffffffff8a159c7e RBX: ffff88804061c000 RCX: ffff8880376b0000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000fffffffc R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed10080c3803 R12: dffffc0000000000 R13: ffff8880374bcb18 R14: ffff88804061cac0 R15: ffff88804061c010 FS: 0000000000000000(0000) GS:ffff88812643f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555c786a28 CR3: 00000000397ce000 CR4: 00000000003526f0 Call Trace: process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 final repro crashed as (corrupted=false): ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 kobject: kobject_add_internal failed for hci1:0 with -EEXIST, don't try to register things with the same name in the same directory. Bluetooth: hci1: failed to register connection device ------------[ cut here ]------------ refcnt < 0 WARNING: net/bluetooth/hci_conn.c:567 at hci_conn_timeout+0xff/0x2c0 net/bluetooth/hci_conn.c:567, CPU#1: kworker/u9:1/5114 Modules linked in: CPU: 1 UID: 0 PID: 5114 Comm: kworker/u9:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026 Workqueue: hci1 hci_conn_timeout RIP: 0010:hci_conn_timeout+0xff/0x2c0 net/bluetooth/hci_conn.c:567 Code: 48 89 df e8 f3 99 09 00 eb 07 e8 6c b7 ae f7 b0 13 0f b6 f0 48 89 df 5b 41 5c 41 5e 41 5f 5d e9 07 a9 fe ff e8 52 b7 ae f7 90 <0f> 0b 90 eb 8c 44 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 31 ff ff ff RSP: 0018:ffffc90011077ad0 EFLAGS: 00010293 RAX: ffffffff8a159c7e RBX: ffff88804061c000 RCX: ffff8880376b0000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000fffffffc R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed10080c3803 R12: dffffc0000000000 R13: ffff8880374bcb18 R14: ffff88804061cac0 R15: ffff88804061c010 FS: 0000000000000000(0000) GS:ffff88812643f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555c786a28 CR3: 00000000397ce000 CR4: 00000000003526f0 Call Trace: process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245