================================================================== BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x101c/0x1090 drivers/hid/hid-mcp2221.c:964 Read of size 1 at addr ffff888129aebfff by task syz.8.2756/18044 CPU: 0 UID: 0 PID: 18044 Comm: syz.8.2756 Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1d0 mm/kasan/report.c:595 mcp2221_raw_event+0x101c/0x1090 drivers/hid/hid-mcp2221.c:964 __hid_input_report.constprop.0+0x319/0x470 drivers/hid/hid-core.c:2161 hid_irq_in+0x55d/0x710 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741 dummy_timer+0xda1/0x36c0 drivers/usb/gadget/udc/dummy_hcd.c:2005 __run_hrtimer kernel/time/hrtimer.c:1930 [inline] __hrtimer_run_queues+0x470/0xa00 kernel/time/hrtimer.c:1994 hrtimer_run_softirq+0x17d/0x2c0 kernel/time/hrtimer.c:2011 handle_softirqs+0x1dd/0x9e0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x160/0x210 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:198 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 96 b8 1e fa 48 89 df e8 6e 08 1f fa f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 45 40 12 fa 65 8b 05 2e 6a 87 05 85 c0 74 16 5b RSP: 0018:ffffc9000348fca0 EFLAGS: 00000246 RAX: 0000000000000006 RBX: ffff8881316da008 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff890c9ef8 RDI: ffffffff87b08200 RBP: 0000000000000283 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffff8881316da198 R15: ffffc9000348fd18 spin_unlock_irqrestore include/linux/spinlock.h:408 [inline] raw_process_ep_io+0x7b0/0xc40 drivers/usb/gadget/legacy/raw_gadget.c:1140 raw_ioctl_ep_write drivers/usb/gadget/legacy/raw_gadget.c:1153 [inline] raw_ioctl+0x25a/0x2b80 drivers/usb/gadget/legacy/raw_gadget.c:1325 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0x7f0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb70dd2caeb Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007fb70c77df60 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fb70dd2caeb RDX: 00007fb70c77dfe0 RSI: 0000000040085507 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007fb70e0d0320 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000200000000140 R13: 0000000000000000 R14: 00007fb70dfa5fa0 R15: 00007ffc023c9a98 Allocated by task 2856: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6e/0x70 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4570 [inline] slab_alloc_node mm/slub.c:4899 [inline] kmem_cache_alloc_noprof+0x2e7/0x6a0 mm/slub.c:4906 alloc_filename fs/namei.c:142 [inline] do_getname+0x35/0x390 fs/namei.c:182 class_filename_flags_constructor include/linux/fs.h:2555 [inline] do_readlinkat+0xa9/0x370 fs/stat.c:569 __do_sys_readlink fs/stat.c:605 [inline] __se_sys_readlink fs/stat.c:602 [inline] __x64_sys_readlink+0x78/0xc0 fs/stat.c:602 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0x7f0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 2856: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x43/0x70 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6251 [inline] kmem_cache_free+0x108/0x660 mm/slub.c:6378 free_filename fs/namei.c:147 [inline] putname+0xb1/0x110 fs/namei.c:306 class_filename_destructor include/linux/fs.h:2553 [inline] class_filename_flags_destructor include/linux/fs.h:2555 [inline] do_readlinkat+0x1f1/0x370 fs/stat.c:569 __do_sys_readlink fs/stat.c:605 [inline] __se_sys_readlink fs/stat.c:602 [inline] __x64_sys_readlink+0x78/0xc0 fs/stat.c:602 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0x7f0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888129aebf00 which belongs to the cache names_cache of size 192 The buggy address is located 63 bytes to the right of allocated 192-byte region [ffff888129aebf00, ffff888129aebfc0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x129aeb flags: 0x200000000000000(node=0|zone=2) page_type: f5(slab) raw: 0200000000000000 ffff8881012ea140 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800100010 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 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2856, tgid 2856 (udevd), ts 1266757550792, free_ts 1265477455330 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1853 prep_new_page mm/page_alloc.c:1861 [inline] get_page_from_freelist+0x20a5/0x3850 mm/page_alloc.c:3941 __alloc_frozen_pages_noprof+0x273/0x28a0 mm/page_alloc.c:5221 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab mm/slub.c:3467 [inline] new_slab+0xa6/0x6b0 mm/slub.c:3525 refill_objects+0x277/0x420 mm/slub.c:7272 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x375/0x650 mm/slub.c:4652 alloc_from_pcs mm/slub.c:4750 [inline] slab_alloc_node mm/slub.c:4884 [inline] kmem_cache_alloc_noprof+0x520/0x6a0 mm/slub.c:4906 alloc_filename fs/namei.c:142 [inline] do_getname+0x35/0x390 fs/namei.c:182 getname include/linux/fs.h:2526 [inline] getname_maybe_null include/linux/fs.h:2533 [inline] class_filename_maybe_null_constructor include/linux/fs.h:2557 [inline] vfs_fstatat+0xd0/0xe0 fs/stat.c:368 __do_sys_newfstatat+0x9d/0x120 fs/stat.c:538 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0x7f0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 16471 tgid 16470 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1397 [inline] __free_frozen_pages+0x6d8/0xf60 mm/page_alloc.c:2938 tlb_batch_list_free mm/mmu_gather.c:161 [inline] tlb_finish_mmu+0x27d/0x810 mm/mmu_gather.c:552 exit_mmap+0x454/0xa10 mm/mmap.c:1313 __mmput kernel/fork.c:1178 [inline] mmput+0xe0/0x430 kernel/fork.c:1201 exit_mm kernel/exit.c:582 [inline] do_exit+0x8b2/0x2af0 kernel/exit.c:964 do_group_exit+0xd5/0x2a0 kernel/exit.c:1119 get_signal+0x20ff/0x2210 kernel/signal.c:3037 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x83/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x682/0x7f0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888129aebe80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888129aebf00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888129aebf80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff888129aec000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888129aec080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: f5 cmc 1: 53 push %rbx 2: 48 8b 74 24 10 mov 0x10(%rsp),%rsi 7: 48 89 fb mov %rdi,%rbx a: 48 83 c7 18 add $0x18,%rdi e: e8 96 b8 1e fa call 0xfa1eb8a9 13: 48 89 df mov %rbx,%rdi 16: e8 6e 08 1f fa call 0xfa1f0889 1b: f7 c5 00 02 00 00 test $0x200,%ebp 21: 75 23 jne 0x46 23: 9c pushf 24: 58 pop %rax 25: f6 c4 02 test $0x2,%ah 28: 75 37 jne 0x61 * 2a: bf 01 00 00 00 mov $0x1,%edi <-- trapping instruction 2f: e8 45 40 12 fa call 0xfa124079 34: 65 8b 05 2e 6a 87 05 mov %gs:0x5876a2e(%rip),%eax # 0x5876a69 3b: 85 c0 test %eax,%eax 3d: 74 16 je 0x55 3f: 5b pop %rbx