================================================================== BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948 Read of size 1 at addr ffff888056273fff by task swapper/1/0 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 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+0x388/0x610 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+0x202/0xad0 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842 handle_softirqs+0x219/0x8e0 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 RIP: 0010:sched_core_balance+0xa0/0xeb0 kernel/sched/core.c:6382 Code: 15 5c 8e e8 62 3a 0d 00 e8 5d 50 0a 0a 41 5b 85 c0 0f 85 31 0a 00 00 4c 89 e7 e8 7b 72 fe ff e8 86 e5 38 00 fb 48 63 44 24 50 <48> c7 c3 00 83 d8 93 48 89 44 24 08 48 83 f8 07 0f 87 9c 0c 00 00 RSP: 0018:ffffc90000197b00 EFLAGS: 00000206 RAX: 0000000000000001 RBX: ffff8880b8523f10 RCX: ffffffff81c3849f RDX: 0000000000000000 RSI: ffffffff8de52e89 RDI: ffffffff8c163400 RBP: ffffc90000197c20 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff90ab7797 R11: 0000000000000000 R12: ffff8880b853a300 R13: ffff88807b8d8000 R14: 0000000000000000 R15: dffffc0000000000 do_balance_callbacks kernel/sched/core.c:5011 [inline] __balance_callbacks kernel/sched/core.c:5065 [inline] finish_lock_switch kernel/sched/core.c:5104 [inline] finish_task_switch.isra.0+0x46f/0xc10 kernel/sched/core.c:5223 context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1198/0x5de0 kernel/sched/core.c:6961 schedule_idle+0x5c/0x90 kernel/sched/core.c:7084 do_idle+0x2b6/0x510 kernel/sched/idle.c:358 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 Allocated by task 2906: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] mca_alloc net/ipv6/mcast.c:876 [inline] __ipv6_dev_mc_inc+0x2f1/0xbc0 net/ipv6/mcast.c:966 addrconf_join_solict net/ipv6/addrconf.c:2246 [inline] addrconf_dad_begin net/ipv6/addrconf.c:4099 [inline] addrconf_dad_work+0x28c/0x14e0 net/ipv6/addrconf.c:4227 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff888056273c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 735 bytes to the right of allocated 288-byte region [ffff888056273c00, ffff888056273d20) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56270 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b841c80 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b841c80 0000000000000000 dead000000000001 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001589c01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 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 2906, tgid 2906 (kworker/u8:6), ts 65906824807, free_ts 16185183968 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:2492 [inline] allocate_slab mm/slub.c:2660 [inline] new_slab+0x247/0x330 mm/slub.c:2714 ___slab_alloc+0xcf2/0x1750 mm/slub.c:3901 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3992 __slab_alloc_node mm/slub.c:4067 [inline] slab_alloc_node mm/slub.c:4228 [inline] __kmalloc_cache_noprof+0xfb/0x3e0 mm/slub.c:4402 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] mca_alloc net/ipv6/mcast.c:876 [inline] __ipv6_dev_mc_inc+0x2f1/0xbc0 net/ipv6/mcast.c:966 addrconf_join_solict net/ipv6/addrconf.c:2246 [inline] addrconf_dad_begin net/ipv6/addrconf.c:4099 [inline] addrconf_dad_work+0x28c/0x14e0 net/ipv6/addrconf.c:4227 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 page last free pid 1 tgid 1 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 __free_pages mm/page_alloc.c:5260 [inline] free_contig_range+0x183/0x4b0 mm/page_alloc.c:7091 destroy_args+0x794/0xc10 mm/debug_vm_pgtable.c:958 debug_vm_pgtable+0x1a32/0x3640 mm/debug_vm_pgtable.c:1345 do_one_initcall+0x120/0x6e0 init/main.c:1269 do_initcall_level init/main.c:1331 [inline] do_initcalls init/main.c:1347 [inline] do_basic_setup init/main.c:1366 [inline] kernel_init_freeable+0x5c2/0x910 init/main.c:1579 kernel_init+0x1c/0x2b0 init/main.c:1469 ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888056273e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888056273f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888056273f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888056274000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888056274080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 15 5c 8e e8 62 adc $0x62e88e5c,%eax 5: 3a 0d 00 e8 5d 50 cmp 0x505de800(%rip),%cl # 0x505de80b b: 0a 0a or (%rdx),%cl d: 41 5b pop %r11 f: 85 c0 test %eax,%eax 11: 0f 85 31 0a 00 00 jne 0xa48 17: 4c 89 e7 mov %r12,%rdi 1a: e8 7b 72 fe ff call 0xfffe729a 1f: e8 86 e5 38 00 call 0x38e5aa 24: fb sti 25: 48 63 44 24 50 movslq 0x50(%rsp),%rax * 2a: 48 c7 c3 00 83 d8 93 mov $0xffffffff93d88300,%rbx <-- trapping instruction 31: 48 89 44 24 08 mov %rax,0x8(%rsp) 36: 48 83 f8 07 cmp $0x7,%rax 3a: 0f 87 9c 0c 00 00 ja 0xcdc