================================================================== BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x10b0/0x12a0 drivers/hid/hid-mcp2221.c:964 Read of size 1 at addr ffff88805de47fff by task ktimers/0/16 CPU: 0 UID: 0 PID: 16 Comm: ktimers/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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 mcp2221_raw_event+0x10b0/0x12a0 drivers/hid/hid-mcp2221.c:964 __hid_input_report+0x421/0x580 drivers/hid/hid-core.c:2168 hid_irq_in+0x492/0x710 drivers/hid/usbhid/hid-core.c:287 __usb_hcd_giveback_urb+0x3b8/0x5f0 drivers/usb/core/hcd.c:1657 dummy_timer+0xaac/0x4d50 drivers/usb/gadget/udc/dummy_hcd.c:2019 __run_hrtimer kernel/time/hrtimer.c:2032 [inline] __hrtimer_run_queues+0x3eb/0xaf0 kernel/time/hrtimer.c:2096 hrtimer_run_softirq+0x18f/0x260 kernel/time/hrtimer.c:2113 handle_softirqs+0x1d9/0x6c0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] run_ktimerd+0x69/0x100 kernel/softirq.c:1151 smpboot_thread_fn+0x57c/0xa80 kernel/smpboot.c:160 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5596: 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_node_noprof+0x3eb/0x670 mm/slub.c:4989 kmalloc_reserve net/core/skbuff.c:615 [inline] __alloc_skb+0x276/0x7a0 net/core/skbuff.c:715 alloc_skb include/linux/skbuff.h:1384 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:517 [inline] hci_cmd_sync_alloc+0x3d/0x3a0 net/bluetooth/hci_sync.c:58 hci_send_cmd+0x46/0x1a0 net/bluetooth/hci_core.c:3061 hci_remote_features_evt+0x292/0x950 net/bluetooth/hci_event.c:3741 hci_event_func net/bluetooth/hci_event.c:7784 [inline] hci_event_packet+0x6cd/0xf10 net/bluetooth/hci_event.c:7835 hci_rx_work+0x3ee/0x1020 net/bluetooth/hci_core.c:4039 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88805de47a80 which belongs to the cache skbuff_small_head of size 704 The buggy address is located 703 bytes to the right of allocated 704-byte region [ffff88805de47a80, ffff88805de47d40) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805de44d00 pfn:0x5de44 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000240(workingset|head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000240 ffff888140af9c80 ffffea00022a7c10 ffffea0000c8d210 raw: ffff88805de44d00 0000000800130008 00000000f5000000 0000000000000000 head: 0080000000000240 ffff888140af9c80 ffffea00022a7c10 ffffea0000c8d210 head: ffff88805de44d00 0000000800130008 00000000f5000000 0000000000000000 head: 0080000000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 9325, tgid 9322 (syz.1.1253), ts 289474739254, free_ts 288806500903 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+0x262a/0x26a0 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+0x2d8/0x350 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x330/0x690 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] kmem_cache_alloc_node_noprof+0x4dc/0x670 mm/slub.c:4989 kmalloc_reserve net/core/skbuff.c:615 [inline] __alloc_skb+0x276/0x7a0 net/core/skbuff.c:715 alloc_skb include/linux/skbuff.h:1384 [inline] alloc_skb_with_frags+0xc6/0x760 net/core/skbuff.c:6775 sock_alloc_send_pskb+0x884/0x9a0 net/core/sock.c:3012 sock_alloc_send_skb include/net/sock.h:1907 [inline] __ip_append_data+0x29ea/0x3cf0 net/ipv4/ip_output.c:1126 ip_make_skb+0x250/0x460 net/ipv4/ip_output.c:1572 udp_sendmsg+0x1937/0x2140 net/ipv4/udp.c:1438 sock_sendmsg_nosec+0x10e/0x180 net/socket.c:776 __sock_sendmsg net/socket.c:790 [inline] ____sys_sendmsg+0x565/0x870 net/socket.c:2684 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738 page last free pid 4943 tgid 4943 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x10e7/0x11c0 mm/page_alloc.c:2950 __slab_free+0x252/0x2a0 mm/slub.c:5741 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 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_node_noprof+0x3eb/0x670 mm/slub.c:4989 __alloc_skb+0x1d7/0x7a0 net/core/skbuff.c:704 alloc_skb include/linux/skbuff.h:1384 [inline] alloc_skb_with_frags+0xc6/0x760 net/core/skbuff.c:6775 sock_alloc_send_pskb+0x884/0x9a0 net/core/sock.c:3012 unix_dgram_sendmsg+0x4da/0x17b0 net/unix/af_unix.c:2137 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775 __sock_sendmsg net/socket.c:790 [inline] __sys_sendto+0x41e/0x5d0 net/socket.c:2252 __do_sys_sendto net/socket.c:2259 [inline] __se_sys_sendto net/socket.c:2255 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2255 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 Memory state around the buggy address: ffff88805de47e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805de47f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805de47f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88805de48000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805de48080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 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