================================================================== BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948 Read of size 1 at addr ffff8881399e7fff by task syz.1.3812/21973 CPU: 1 UID: 0 PID: 21973 Comm: syz.1.3812 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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+0x314/0x450 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+0x1809/0x3a00 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x202/0xad0 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858 handle_softirqs+0x208/0x8d0 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:1052 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:finish_task_switch.isra.0+0x1e9/0x9e0 kernel/sched/core.c:5193 Code: 0f 85 5f 07 00 00 8b 0d 79 c4 51 09 85 c9 0f 85 b9 02 00 00 48 89 df e8 c5 dc f7 05 e8 40 10 37 00 fb 65 48 8b 1d 1f cc 48 0b <48> 8d bb 50 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 RSP: 0018:ffffc900005b7d40 EFLAGS: 00000206 RAX: 0000000000000753 RBX: ffff88811e8b5700 RCX: ffffffff8186432f RDX: 0000000000000000 RSI: ffffffff88c88a08 RDI: ffffffff878979c0 RBP: ffffc900005b7d80 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8aa0ebd7 R11: 0000000000000001 R12: ffff888126048000 R13: 0000000000000000 R14: ffff8881f5938918 R15: ffff8881f5939418 context_switch kernel/sched/core.c:5328 [inline] __schedule+0x1304/0x3b80 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7026 exit_to_user_mode_loop+0x5c/0xe0 kernel/entry/common.c:31 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x40f/0x4d0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb01349f6c9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffee715af88 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007fb0136f5fa8 RCX: 00007fb01349f6c9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fb0136f5fa8 RBP: 0000000000000000 R08: 0000000000000001 R09: 00000006e715b27f R10: 00007fb0136f5fa0 R11: 0000000000000246 R12: 00007fb0136f5fac R13: 00007fb0136f5fa0 R14: 0000000000001d8e R15: 0000000000000004 Allocated by task 2857: 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:342 [inline] __kasan_slab_alloc+0x6e/0x70 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4970 [inline] slab_alloc_node mm/slub.c:5280 [inline] kmem_cache_alloc_noprof+0x260/0x6c0 mm/slub.c:5287 getname_flags.part.0+0x4c/0x550 fs/namei.c:146 getname_flags+0x93/0xf0 include/linux/audit.h:345 getname include/linux/fs.h:2922 [inline] do_sys_openat2+0xb8/0x1d0 fs/open.c:1431 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 2857: 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:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] 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:2539 [inline] slab_free mm/slub.c:6630 [inline] kmem_cache_free+0x2a4/0x660 mm/slub.c:6740 putname+0x154/0x1a0 fs/namei.c:297 do_sys_openat2+0x152/0x1d0 fs/open.c:1445 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8881399e6600 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 [ffff8881399e6600, ffff8881399e7600) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1399e0 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 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000 head: 0200000000000040 ffff8881012a1000 dead000000000122 0000000000000000 head: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000 head: 0200000000000003 ffffea0004e67801 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 8367, tgid 8367 (udevd), ts 1990716616844, free_ts 1952252855362 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x1003/0x2dc0 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x259/0x21f0 mm/page_alloc.c:5183 alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3055 [inline] allocate_slab mm/slub.c:3228 [inline] new_slab+0x24a/0x360 mm/slub.c:3282 ___slab_alloc+0xdb7/0x1a70 mm/slub.c:4651 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4770 __slab_alloc_node mm/slub.c:4846 [inline] slab_alloc_node mm/slub.c:5268 [inline] kmem_cache_alloc_noprof+0x393/0x6c0 mm/slub.c:5287 getname_flags.part.0+0x4c/0x550 fs/namei.c:146 getname_flags+0x93/0xf0 include/linux/audit.h:345 getname include/linux/fs.h:2922 [inline] do_sys_openat2+0xb8/0x1d0 fs/open.c:1431 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5192 tgid 5192 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0x78f/0x1000 mm/page_alloc.c:2906 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x4e/0x70 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4970 [inline] slab_alloc_node mm/slub.c:5280 [inline] kmem_cache_alloc_noprof+0x260/0x6c0 mm/slub.c:5287 getname_flags.part.0+0x4c/0x550 fs/namei.c:146 getname_flags+0x93/0xf0 include/linux/audit.h:345 getname include/linux/fs.h:2922 [inline] do_sys_openat2+0xb8/0x1d0 fs/open.c:1431 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff8881399e7e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881399e7f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881399e7f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881399e8000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881399e8080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 0f 85 5f 07 00 00 jne 0x765 6: 8b 0d 79 c4 51 09 mov 0x951c479(%rip),%ecx # 0x951c485 c: 85 c9 test %ecx,%ecx e: 0f 85 b9 02 00 00 jne 0x2cd 14: 48 89 df mov %rbx,%rdi 17: e8 c5 dc f7 05 call 0x5f7dce1 1c: e8 40 10 37 00 call 0x371061 21: fb sti 22: 65 48 8b 1d 1f cc 48 mov %gs:0xb48cc1f(%rip),%rbx # 0xb48cc49 29: 0b * 2a: 48 8d bb 50 15 00 00 lea 0x1550(%rbx),%rdi <-- trapping instruction 31: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 38: fc ff df 3b: 48 89 fa mov %rdi,%rdx 3e: 48 rex.W 3f: c1 .byte 0xc1