================================================================== BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948 Read of size 1 at addr ffff88807d233fff by task ksoftirqd/1/23 CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948 __hid_input_report.constprop.0+0x311/0x450 drivers/hid/hid-core.c:2130 hid_irq_in+0x35e/0x870 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x38b/0x610 drivers/usb/core/hcd.c:1661 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1745 dummy_timer+0x1814/0x3a30 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579 run_ksoftirqd kernel/softirq.c:968 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:960 smpboot_thread_fn+0x3f4/0xae0 kernel/smpboot.c:160 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 16898: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4236 sctp_chunkify+0x51/0x2d0 net/sctp/sm_make_chunk.c:1373 _sctp_make_chunk+0x148/0x270 net/sctp/sm_make_chunk.c:1446 sctp_make_data net/sctp/sm_make_chunk.c:1467 [inline] sctp_make_datafrag_empty+0x16f/0x240 net/sctp/sm_make_chunk.c:732 sctp_datamsg_from_user+0x592/0x1320 net/sctp/chunk.c:262 sctp_sendmsg_to_asoc+0xaf5/0x1bf0 net/sctp/socket.c:1860 sctp_sendmsg+0xea2/0x1e10 net/sctp/socket.c:2032 inet_sendmsg+0x11c/0x140 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] __sys_sendto+0x43c/0x520 net/socket.c:2228 __do_sys_sendto net/socket.c:2235 [inline] __se_sys_sendto net/socket.c:2231 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2231 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 16898: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x60/0x70 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4782 sctp_chunk_destroy net/sctp/sm_make_chunk.c:1499 [inline] sctp_chunk_put+0x205/0x2c0 net/sctp/sm_make_chunk.c:1522 sctp_datamsg_destroy net/sctp/chunk.c:111 [inline] sctp_datamsg_put+0x124/0x5f0 net/sctp/chunk.c:128 sctp_chunk_free+0x45/0x60 net/sctp/sm_make_chunk.c:1507 __sctp_outq_teardown+0x70a/0xc40 net/sctp/outqueue.c:257 sctp_association_free+0x210/0x7e0 net/sctp/associola.c:340 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:950 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1336 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1204 [inline] sctp_do_sm+0x22dc/0x5c80 net/sctp/sm_sideeffect.c:1175 sctp_primitive_ABORT+0x9f/0xd0 net/sctp/primitive.c:104 sctp_close+0x230/0x940 net/sctp/socket.c:1527 inet_release+0xea/0x200 net/ipv4/af_inet.c:435 inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:487 __sock_release+0xb0/0x270 net/socket.c:649 sock_close+0x1c/0x30 net/socket.c:1439 __fput+0x3ff/0xb70 fs/file_table.c:468 fput_close_sync+0x118/0x210 fs/file_table.c:573 __do_sys_close fs/open.c:1587 [inline] __se_sys_close fs/open.c:1572 [inline] __x64_sys_close+0x8b/0x120 fs/open.c:1572 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807d233dc0 which belongs to the cache sctp_chunk of size 256 The buggy address is located 319 bytes to the right of allocated 256-byte region [ffff88807d233dc0, ffff88807d233ec0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7d233 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88814c689140 dead000000000122 0000000000000000 raw: 0000000000000000 00000000000c000c 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 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 16898, tgid 16886 (syz.5.1981), ts 672668935624, free_ts 671790650609 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab mm/slub.c:2655 [inline] new_slab+0x247/0x330 mm/slub.c:2709 ___slab_alloc+0xcf2/0x1740 mm/slub.c:3891 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981 __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_noprof+0xef/0x3b0 mm/slub.c:4236 sctp_chunkify+0x51/0x2d0 net/sctp/sm_make_chunk.c:1373 _sctp_make_chunk+0x148/0x270 net/sctp/sm_make_chunk.c:1446 sctp_make_data net/sctp/sm_make_chunk.c:1467 [inline] sctp_make_datafrag_empty+0x16f/0x240 net/sctp/sm_make_chunk.c:732 sctp_datamsg_from_user+0x592/0x1320 net/sctp/chunk.c:262 sctp_sendmsg_to_asoc+0xaf5/0x1bf0 net/sctp/socket.c:1860 sctp_sendmsg+0xea2/0x1e10 net/sctp/socket.c:2032 inet_sendmsg+0x11c/0x140 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] __sys_sendto+0x43c/0x520 net/socket.c:2228 page last free pid 0 tgid 0 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895 pagetable_free include/linux/mm.h:2898 [inline] pagetable_dtor_free include/linux/mm.h:2996 [inline] __tlb_remove_table include/asm-generic/tlb.h:220 [inline] __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x116/0x1a0 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0x799/0x1530 kernel/rcu/tree.c:2861 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 Memory state around the buggy address: ffff88807d233e80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88807d233f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807d233f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88807d234000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88807d234080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================