================================================================== BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948 Read of size 1 at addr ffff888109faffff by task syz.0.2777/15499 CPU: 1 UID: 0 PID: 15499 Comm: syz.0.2777 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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+0x314/0x470 drivers/hid/hid-core.c:2139 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+0x1809/0x3ad0 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858 handle_softirqs+0x208/0x940 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xfa/0x160 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+0x90/0xb0 arch/x86/kernel/apic/apic.c:1056 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:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 c6 4c 02 fa 48 89 df e8 7e 9f 02 fa f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 c5 f2 f5 f9 65 8b 05 de 46 49 05 85 c0 74 16 5b RSP: 0018:ffffc900146a7c60 EFLAGS: 00000246 RAX: 0000000000000006 RBX: ffff8881f57280c0 RCX: ffffffff818802ef RDX: 0000000000000000 RSI: ffffffff88d033a4 RDI: ffffffff878a7180 RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8aa48bd7 R11: ffffffff93b66460 R12: dffffc0000000000 R13: ffffc900146a7db8 R14: 0000000000000001 R15: ffff888119750018 hrtimer_start_expires include/linux/hrtimer.h:273 [inline] hrtimer_sleeper_start_expires kernel/time/hrtimer.c:2039 [inline] do_nanosleep+0x1f6/0x580 kernel/time/hrtimer.c:2113 hrtimer_nanosleep+0x155/0x380 kernel/time/hrtimer.c:2163 common_nsleep+0xa1/0xd0 kernel/time/posix-timers.c:1352 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1398 [inline] __se_sys_clock_nanosleep kernel/time/posix-timers.c:1375 [inline] __x64_sys_clock_nanosleep+0x34d/0x4a0 kernel/time/posix-timers.c:1375 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcc35b82005 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007fcc345adf60 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fcc35b82005 RDX: 00007fcc345adfa0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000200000000040 R13: 0000000000000000 R14: 00007fcc35da5fa0 R15: 00007ffd564ab778 Allocated by task 15476: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6e/0x70 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4948 [inline] slab_alloc_node mm/slub.c:5258 [inline] kmem_cache_alloc_noprof+0x26e/0x740 mm/slub.c:5265 getname_flags.part.0+0x4c/0x550 fs/namei.c:146 getname_flags+0x93/0xf0 include/linux/audit.h:345 getname include/linux/fs.h:2498 [inline] do_sys_openat2+0xb8/0x250 fs/open.c:1426 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 15476: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x43/0x70 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6663 [inline] kmem_cache_free+0x2a7/0x710 mm/slub.c:6774 putname+0xf5/0x1a0 fs/namei.c:297 __free_putname include/linux/fs.h:2512 [inline] do_sys_openat2+0x177/0x250 fs/open.c:1419 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888109fae600 which belongs to the cache names_cache of size 4096 The buggy address is located 2559 bytes to the right of allocated 4096-byte region [ffff888109fae600, ffff888109faf600) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x109fa8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x200000000000040(head|node=0|zone=2) page_type: f5(slab) raw: 0200000000000040 ffff8881012a1000 ffffea0004643400 dead000000000002 raw: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000 head: 0200000000000040 ffff8881012a1000 ffffea0004643400 dead000000000002 head: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000 head: 0200000000000003 ffffea000427ea01 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2863, tgid 2863 (udevd), ts 1013558201452, free_ts 1012428387151 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x1058/0x3cb0 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x259/0x21c0 mm/page_alloc.c:5210 alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x2c3/0x430 mm/slub.c:3302 ___slab_alloc+0xe20/0x1ca0 mm/slub.c:4651 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4774 __slab_alloc_node mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:5246 [inline] kmem_cache_alloc_noprof+0x3a1/0x740 mm/slub.c:5265 getname_flags.part.0+0x4c/0x550 fs/namei.c:146 getname_flags+0x93/0xf0 include/linux/audit.h:345 getname include/linux/fs.h:2498 [inline] do_sys_openat2+0xb8/0x250 fs/open.c:1426 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 2863 tgid 2863 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x795/0x1010 mm/page_alloc.c:2943 discard_slab mm/slub.c:3346 [inline] __put_partials+0x130/0x170 mm/slub.c:3886 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4c/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x4e/0x70 mm/kasan/common.c:349 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4948 [inline] slab_alloc_node mm/slub.c:5258 [inline] kmem_cache_alloc_node_noprof+0x2a8/0x7e0 mm/slub.c:5310 __alloc_skb+0x156/0x410 net/core/skbuff.c:679 alloc_skb include/linux/skbuff.h:1383 [inline] netlink_alloc_large_skb+0x69/0x140 net/netlink/af_netlink.c:1184 netlink_sendmsg+0x698/0xdd0 net/netlink/af_netlink.c:1869 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2646 __sys_sendmsg+0x16d/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888109fafe80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888109faff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888109faff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888109fb0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888109fb0080: 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 c6 4c 02 fa call 0xfa024cd9 13: 48 89 df mov %rbx,%rdi 16: e8 7e 9f 02 fa call 0xfa029f99 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 c5 f2 f5 f9 call 0xf9f5f2f9 34: 65 8b 05 de 46 49 05 mov %gs:0x54946de(%rip),%eax # 0x5494719 3b: 85 c0 test %eax,%eax 3d: 74 16 je 0x55 3f: 5b pop %rbx