syzbot

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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
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