================================================================== BUG: KASAN: use-after-free in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948 Read of size 1 at addr ffff888054d23fff by task udevd/5221 CPU: 0 UID: 0 PID: 5221 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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+0x38b/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+0x1ff/0xad0 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842 handle_softirqs+0x216/0x8e0 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:lock_release+0x183/0x2f0 kernel/locking/lockdep.c:5893 Code: 0f c1 05 f8 fd 3e 12 83 f8 01 0f 85 1d 01 00 00 9c 58 f6 c4 02 0f 85 08 01 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 0d bc 3e 12 0f 85 58 01 00 00 48 83 c4 18 5b 41 5c 41 RSP: 0018:ffffc90003217860 EFLAGS: 00000206 RAX: 128a1889f02ba000 RBX: ffffffff8e5c1260 RCX: ffffc9000321786c RDX: 0000000000000000 RSI: ffffffff8de2b530 RDI: ffffffff8c162a00 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 00000000000061ee R12: ffffffff816ae8a4 R13: 0000000000000202 R14: ffff8880794c4880 R15: 0000000000000001 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x3f9/0x20a0 arch/x86/kernel/unwind_orc.c:479 __unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0x73/0x100 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x60/0x70 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4782 putname+0x154/0x1a0 fs/namei.c:297 vfs_fstatat+0x85/0xf0 fs/stat.c:376 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9bfcb11b0a Code: 48 8b 15 f1 f2 0d 00 f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 b9 f2 0d 00 f7 RSP: 002b:00007ffdc6775958 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 0000562c64c4e430 RCX: 00007f9bfcb11b0a RDX: 00007ffdc6775960 RSI: 0000562c64c3cee9 RDI: 00000000ffffff9c RBP: 0000562c873d4668 R08: 00063478c1c69200 R09: 00007f9bfd3d5000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffdc6775960 R14: 0000000000000000 R15: 00063478c1c69200 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x54d23 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 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5859, tgid 5859 (udevd), ts 71485512442, free_ts 120472959539 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:2487 [inline] allocate_slab mm/slub.c:2655 [inline] new_slab+0x247/0x330 mm/slub.c:2709 ___slab_alloc+0xcf2/0x1740 mm/slub.c:3891 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981 __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_node_noprof+0xf5/0x3b0 mm/slub.c:4281 kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:578 __alloc_skb+0x166/0x380 net/core/skbuff.c:669 alloc_skb include/linux/skbuff.h:1336 [inline] netlink_alloc_large_skb+0x69/0x130 net/netlink/af_netlink.c:1186 netlink_sendmsg+0x6a1/0xdd0 net/netlink/af_netlink.c:1871 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa98/0xc70 net/socket.c:2614 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668 __sys_sendmsg+0x16d/0x220 net/socket.c:2700 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 page last free pid 6627 tgid 6625 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 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+0x69/0x90 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] __kmalloc_cache_node_noprof+0x217/0x420 mm/slub.c:4404 kmalloc_node_noprof include/linux/slab.h:928 [inline] alloc_user_cpus_ptr kernel/sched/sched.h:2588 [inline] sched_setaffinity+0x265/0x400 kernel/sched/syscalls.c:1235 __do_sys_sched_setaffinity kernel/sched/syscalls.c:1284 [inline] __se_sys_sched_setaffinity kernel/sched/syscalls.c:1273 [inline] __x64_sys_sched_setaffinity+0x116/0x140 kernel/sched/syscalls.c:1273 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888054d23e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888054d23f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888054d23f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888054d24000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888054d24080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 0f c1 05 f8 fd 3e 12 xadd %eax,0x123efdf8(%rip) # 0x123efdff 7: 83 f8 01 cmp $0x1,%eax a: 0f 85 1d 01 00 00 jne 0x12d 10: 9c pushf 11: 58 pop %rax 12: f6 c4 02 test $0x2,%ah 15: 0f 85 08 01 00 00 jne 0x123 1b: 41 f7 c5 00 02 00 00 test $0x200,%r13d 22: 74 01 je 0x25 24: fb sti 25: 48 8b 44 24 10 mov 0x10(%rsp),%rax * 2a: 65 48 2b 05 0d bc 3e sub %gs:0x123ebc0d(%rip),%rax # 0x123ebc3f <-- trapping instruction 31: 12 32: 0f 85 58 01 00 00 jne 0x190 38: 48 83 c4 18 add $0x18,%rsp 3c: 5b pop %rbx 3d: 41 5c pop %r12 3f: 41 rex.B