================================================================== BUG: KASAN: use-after-free in mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:950 Read of size 1 at addr ffff888059ab7fff by task udevd/5193 CPU: 0 UID: 0 PID: 5193 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:950 __hid_input_report drivers/hid/hid-core.c:2140 [inline] hid_input_report+0x41d/0x580 drivers/hid/hid-core.c:2167 hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1657 dummy_timer+0xbbd/0x45d0 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1785 [inline] __hrtimer_run_queues+0x53a/0xcc0 kernel/time/hrtimer.c:1849 hrtimer_run_softirq+0x182/0x5a0 kernel/time/hrtimer.c:1866 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872 Code: e9 30 ff ff ff e8 85 f4 0d 0a f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 01 02 7b 11 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 3e 95 73 RSP: 0018:ffffc900031f7c68 EFLAGS: 00000282 RAX: f7b4d27e59a7fb00 RBX: 0000000000000246 RCX: 0000000000000046 RDX: 000000008f6593ba RSI: ffffffff8e16b7af RDI: ffffffff8c27d100 RBP: 0000000000000000 R08: ffffffff826f518c R09: ffffffff8e75e5e0 R10: dffffc0000000000 R11: ffffed1004b26c01 R12: 0000000000000002 R13: ffffffff8e75e5e0 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] kernfs_root+0x38/0x230 fs/kernfs/kernfs-internal.h:75 kernfs_active fs/kernfs/dir.c:39 [inline] kernfs_dir_next_pos fs/kernfs/dir.c:1881 [inline] kernfs_fop_readdir+0x605/0x8d0 fs/kernfs/dir.c:1905 iterate_dir+0x399/0x570 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:412 [inline] __se_sys_getdents64+0xf1/0x280 fs/readdir.c:397 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3aaf0f0d23 Code: 8b 05 d9 00 10 00 64 c7 00 16 00 00 00 31 c0 eb b0 66 0f 1f 44 00 00 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 a1 00 10 00 f7 d8 RSP: 002b:00007ffeddfac3a8 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 000055bca13b8920 RCX: 00007f3aaf0f0d23 RDX: 0000000000008000 RSI: 000055bca13b8950 RDI: 000000000000000e RBP: 000055bca13b8924 R08: 0000000000000802 R09: 0000000000000000 R10: 00007f3aaf1f2270 R11: 0000000000000293 R12: 000055bca13b8950 R13: fffffffffffffe68 R14: 0000000000000002 R15: 00007ffeddfac690 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x59ab7 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5846, tgid 5846 (syz-executor), ts 132982015158, free_ts 147091625918 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250 alloc_slab_page mm/slub.c:3292 [inline] allocate_slab+0x77/0x660 mm/slub.c:3481 new_slab mm/slub.c:3539 [inline] refill_objects+0x331/0x3c0 mm/slub.c:7175 refill_sheaf mm/slub.c:2812 [inline] __pcs_replace_empty_main+0x2e6/0x730 mm/slub.c:4615 alloc_from_pcs mm/slub.c:4717 [inline] slab_alloc_node mm/slub.c:4851 [inline] __do_kmalloc_node mm/slub.c:5259 [inline] __kmalloc_noprof+0x474/0x760 mm/slub.c:5272 kmalloc_noprof include/linux/slab.h:954 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x283/0x560 security/tomoyo/file.c:827 security_inode_getattr+0x12b/0x310 security/security.c:1870 vfs_getattr+0x23/0x70 fs/stat.c:259 vfs_statx_path+0x2b/0x230 fs/stat.c:299 vfs_statx+0x12e/0x200 fs/stat.c:356 do_statx fs/stat.c:761 [inline] __do_sys_statx fs/stat.c:814 [inline] __se_sys_statx+0x1e9/0x2a0 fs/stat.c:804 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x20d/0x640 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 page last free pid 6806 tgid 6806 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978 __slab_free+0x263/0x2b0 mm/slub.c:5573 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 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:4538 [inline] slab_alloc_node mm/slub.c:4866 [inline] kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4873 anon_vma_alloc mm/rmap.c:94 [inline] __anon_vma_prepare+0x117/0x4a0 mm/rmap.c:201 __vmf_anon_prepare mm/memory.c:3734 [inline] vmf_anon_prepare mm/internal.h:502 [inline] do_anonymous_page mm/memory.c:5262 [inline] do_pte_missing+0x2dd1/0x3490 mm/memory.c:4475 handle_pte_fault mm/memory.c:6317 [inline] __handle_mm_fault mm/memory.c:6455 [inline] handle_mm_fault+0x1bec/0x3310 mm/memory.c:6624 do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 Memory state around the buggy address: ffff888059ab7e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888059ab7f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888059ab7f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888059ab8000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888059ab8080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: e9 30 ff ff ff jmp 0xffffff35 5: e8 85 f4 0d 0a call 0xa0df48f a: f7 c3 00 02 00 00 test $0x200,%ebx 10: 0f 84 38 ff ff ff je 0xffffff4e 16: 65 48 8b 05 01 02 7b mov %gs:0x117b0201(%rip),%rax # 0x117b021f 1d: 11 1e: 48 3b 44 24 30 cmp 0x30(%rsp),%rax 23: 75 33 jne 0x58 25: fb sti 26: 48 83 c4 38 add $0x38,%rsp * 2a: 5b pop %rbx <-- trapping instruction 2b: 41 5c pop %r12 2d: 41 5d pop %r13 2f: 41 5e pop %r14 31: 41 5f pop %r15 33: 5d pop %rbp 34: c3 ret 35: cc int3 36: cc int3 37: cc int3 38: cc int3 39: cc int3 3a: 48 rex.W 3b: 8d .byte 0x8d 3c: 3d .byte 0x3d 3d: 3e 95 ds xchg %eax,%ebp 3f: 73 .byte 0x73