Extracting prog: 8m6.707298392s
Minimizing prog: 10m28.737022043s
Simplifying prog options: 0s
Extracting C: 1m17.755049888s
Simplifying C: 38m25.0557388s


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_init_net_socket$bt_l2cap-connect$bt_l2cap
detailed listing:
executing program 0:
syz_emit_vhci(&(0x7f00000001c0)=@HCI_ACLDATA_PKT={0x2, {0xc8, 0x0, 0x0, 0x4}, @l2cap_cid_signaling={{0x0, 0x2}}}, 0x9)
r0 = syz_init_net_socket$bt_l2cap(0x1f, 0x3, 0x0)
connect$bt_l2cap(r0, &(0x7f0000000040)={0x1f, 0x0, @fixed={'\xaa\xaa\xaa\xaa\xaa', 0x10}}, 0xe)

program did not crash
single: failed to extract reproducer
single: executing 1 programs separately with timeout 1m40s
testing program (duration=1m40s, {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_init_net_socket$bt_l2cap-connect$bt_l2cap
detailed listing:
executing program 0:
syz_emit_vhci(&(0x7f00000001c0)=@HCI_ACLDATA_PKT={0x2, {0xc8, 0x0, 0x0, 0x4}, @l2cap_cid_signaling={{0x0, 0x2}}}, 0x9)
r0 = syz_init_net_socket$bt_l2cap(0x1f, 0x3, 0x0)
connect$bt_l2cap(r0, &(0x7f0000000040)={0x1f, 0x0, @fixed={'\xaa\xaa\xaa\xaa\xaa', 0x10}}, 0xe)

program crashed: KMSAN: uninit-value in l2cap_recv_frame
single: successfully extracted reproducer
found reproducer with 3 syscalls
minimizing guilty program
testing program (duration=2m6.758419708s, {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_init_net_socket$bt_l2cap
detailed listing:
executing program 0:
syz_emit_vhci(&(0x7f00000001c0)=@HCI_ACLDATA_PKT={0x2, {0xc8, 0x0, 0x0, 0x4}, @l2cap_cid_signaling={{0x0, 0x2}}}, 0x9)
syz_init_net_socket$bt_l2cap(0x1f, 0x3, 0x0)

program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing program (duration=2m6.758419708s, {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(&(0x7f00000001c0)=@HCI_ACLDATA_PKT={0x2, {0xc8, 0x0, 0x0, 0x4}, @l2cap_cid_signaling={{0x0, 0x2}}}, 0x9)

program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing program (duration=2m6.758419708s, {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(0x0, 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=2m6.758419708s, {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
program crashed: KMSAN: uninit-value in l2cap_recv_frame
simplifying C reproducer
testing compiled C program (duration=2m6.758419708s, {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
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false 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
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci
program did not crash
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false 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
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false 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
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false 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
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false 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
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false 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
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false 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
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false 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
program did not crash
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false 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
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:false Swap:true UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing compiled C program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci
program crashed: KMSAN: uninit-value in l2cap_recv_frame
testing program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci
detailed listing:
executing program 0:
syz_emit_vhci(&(0x7f00000001c0)=@HCI_ACLDATA_PKT={0x2, {0xc8, 0x0, 0x0, 0x4}, @l2cap_cid_signaling={{0x0, 0x2}}}, 0x9)

program crashed: KMSAN: uninit-value in l2cap_recv_frame
validation run: crashed=true
testing program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci
detailed listing:
executing program 0:
syz_emit_vhci(&(0x7f00000001c0)=@HCI_ACLDATA_PKT={0x2, {0xc8, 0x0, 0x0, 0x4}, @l2cap_cid_signaling={{0x0, 0x2}}}, 0x9)

program crashed: KMSAN: uninit-value in l2cap_recv_frame
validation run: crashed=true
testing program (duration=2m6.758419708s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_emit_vhci
detailed listing:
executing program 0:
syz_emit_vhci(&(0x7f00000001c0)=@HCI_ACLDATA_PKT={0x2, {0xc8, 0x0, 0x0, 0x4}, @l2cap_cid_signaling={{0x0, 0x2}}}, 0x9)

program crashed: KMSAN: uninit-value in l2cap_recv_frame
validation run: crashed=true
reproducing took 1h7m45.378704863s
repro crashed as (corrupted=false):
=====================================================
BUG: KMSAN: uninit-value in l2cap_conless_channel net/bluetooth/l2cap_core.c:6772 [inline]
BUG: KMSAN: uninit-value in l2cap_recv_frame+0xc3ae/0x187c0 net/bluetooth/l2cap_core.c:6846
 l2cap_conless_channel net/bluetooth/l2cap_core.c:6772 [inline]
 l2cap_recv_frame+0xc3ae/0x187c0 net/bluetooth/l2cap_core.c:6846
 l2cap_recv_acldata+0xe91/0x1de0 net/bluetooth/l2cap_core.c:7574
 hci_acldata_packet net/bluetooth/hci_core.c:3854 [inline]
 hci_rx_work+0x688/0xfc0 net/bluetooth/hci_core.c:4081
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xb91/0x1d80 kernel/workqueue.c:3340
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3421
 kthread+0xd5c/0xf00 kernel/kthread.c:463
 ret_from_fork+0x208/0x710 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Uninit was stored to memory at:
 l2cap_recv_frame+0xc3a7/0x187c0 net/bluetooth/l2cap_core.c:6844
 l2cap_recv_acldata+0xe91/0x1de0 net/bluetooth/l2cap_core.c:7574
 hci_acldata_packet net/bluetooth/hci_core.c:3854 [inline]
 hci_rx_work+0x688/0xfc0 net/bluetooth/hci_core.c:4081
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xb91/0x1d80 kernel/workqueue.c:3340
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3421
 kthread+0xd5c/0xf00 kernel/kthread.c:463
 ret_from_fork+0x208/0x710 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4960 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x9e7/0x17a0 mm/slub.c:5315
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:586
 __alloc_skb+0x805/0x1040 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:510 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:496 [inline]
 vhci_write+0x125/0x960 drivers/bluetooth/hci_vhci.c:616
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0xbe2/0x15d0 fs/read_write.c:686
 ksys_write fs/read_write.c:738 [inline]
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746
 x64_sys_call+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 51 Comm: kworker/u9:0 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: hci0 hci_rx_work
=====================================================

final repro crashed as (corrupted=false):
=====================================================
BUG: KMSAN: uninit-value in l2cap_conless_channel net/bluetooth/l2cap_core.c:6772 [inline]
BUG: KMSAN: uninit-value in l2cap_recv_frame+0xc3ae/0x187c0 net/bluetooth/l2cap_core.c:6846
 l2cap_conless_channel net/bluetooth/l2cap_core.c:6772 [inline]
 l2cap_recv_frame+0xc3ae/0x187c0 net/bluetooth/l2cap_core.c:6846
 l2cap_recv_acldata+0xe91/0x1de0 net/bluetooth/l2cap_core.c:7574
 hci_acldata_packet net/bluetooth/hci_core.c:3854 [inline]
 hci_rx_work+0x688/0xfc0 net/bluetooth/hci_core.c:4081
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xb91/0x1d80 kernel/workqueue.c:3340
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3421
 kthread+0xd5c/0xf00 kernel/kthread.c:463
 ret_from_fork+0x208/0x710 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Uninit was stored to memory at:
 l2cap_recv_frame+0xc3a7/0x187c0 net/bluetooth/l2cap_core.c:6844
 l2cap_recv_acldata+0xe91/0x1de0 net/bluetooth/l2cap_core.c:7574
 hci_acldata_packet net/bluetooth/hci_core.c:3854 [inline]
 hci_rx_work+0x688/0xfc0 net/bluetooth/hci_core.c:4081
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xb91/0x1d80 kernel/workqueue.c:3340
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3421
 kthread+0xd5c/0xf00 kernel/kthread.c:463
 ret_from_fork+0x208/0x710 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4960 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x9e7/0x17a0 mm/slub.c:5315
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:586
 __alloc_skb+0x805/0x1040 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:510 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:496 [inline]
 vhci_write+0x125/0x960 drivers/bluetooth/hci_vhci.c:616
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0xbe2/0x15d0 fs/read_write.c:686
 ksys_write fs/read_write.c:738 [inline]
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746
 x64_sys_call+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 51 Comm: kworker/u9:0 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: hci0 hci_rx_work
=====================================================