================================================================== BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:948 Read of size 1 at addr ffff88802fe17fff by task syz.2.170/6365 CPU: 0 UID: 0 PID: 6365 Comm: syz.2.170 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:948 __hid_input_report drivers/hid/hid-core.c:2139 [inline] hid_input_report+0x41d/0x580 drivers/hid/hid-core.c:2166 hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1661 dummy_timer+0x85f/0x45b0 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1858 handle_softirqs+0x286/0x870 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:727 irq_exit_rcu+0x9/0x30 kernel/softirq.c:743 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:check_preemption_disabled+0x49/0x120 lib/smp_processor_id.c:53 Code: 8b 0d 0b 02 1d 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d eb 01 1d 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f <5d> e9 91 cf 02 00 cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 RSP: 0018:ffffc9000400f648 EFLAGS: 00000286 RAX: 0000000000000000 RBX: ffffffff8b57115a RCX: 53b2867aaeef3800 RDX: 0000000000000001 RSI: ffffffff8bbf3240 RDI: ffffffff8bbf3200 RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff8173dfc5 R10: ffffc9000400f798 R11: ffffffff81ad2830 R12: 1ffff92000801ee9 R13: ffffc9000400f780 R14: ffffc9000400f748 R15: ffffffff8173dfc5 rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:751 rcu_read_lock include/linux/rcupdate.h:868 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xd4/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2547 [inline] slab_free mm/slub.c:6642 [inline] kfree+0x19a/0x6d0 mm/slub.c:6849 raw_ioctl+0x1fca/0x4050 drivers/usb/gadget/legacy/raw_gadget.c:-1 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f092738f2cb 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:00007f0928180f70 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f092738f2cb RDX: 00007f0928180ff0 RSI: 0000000040085507 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007f0927710320 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00002000000004c0 R13: 0000000000000000 R14: 00007f09275e5fa0 R15: 00007fffa0da8e18 Allocated by task 5824: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5654 [inline] __kmalloc_node_track_caller_noprof+0x571/0x810 mm/slub.c:5763 kmemdup_noprof+0x2b/0x70 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:765 [inline] cache_create_net+0x2f/0x260 net/sunrpc/cache.c:1743 nfsd_export_init+0x59/0x1f0 fs/nfsd/export.c:1492 nfsd_net_init+0x2f/0x480 fs/nfsd/nfsctl.c:2148 ops_init+0x35c/0x5c0 net/core/net_namespace.c:137 setup_net+0x110/0x330 net/core/net_namespace.c:446 copy_net_ns+0x34e/0x560 net/core/net_namespace.c:581 create_new_namespaces+0x3d3/0x710 kernel/nsproxy.c:111 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:222 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3129 __do_sys_unshare kernel/fork.c:3200 [inline] __se_sys_unshare kernel/fork.c:3198 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3198 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802fe17c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 743 bytes to the right of allocated 280-byte region [ffff88802fe17c00, ffff88802fe17d18) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2fe14 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813ff26c80 ffffea00014e6a00 dead000000000002 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813ff26c80 ffffea00014e6a00 dead000000000002 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0000bf8501 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5198, tgid 5198 (udevadm), ts 29045089304, free_ts 28902418132 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3920 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5214 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2479 alloc_slab_page mm/slub.c:3063 [inline] allocate_slab+0x96/0x350 mm/slub.c:3236 new_slab mm/slub.c:3290 [inline] ___slab_alloc+0xf56/0x1990 mm/slub.c:4659 __slab_alloc+0x65/0x100 mm/slub.c:4782 __slab_alloc_node mm/slub.c:4858 [inline] slab_alloc_node mm/slub.c:5280 [inline] __kmalloc_cache_noprof+0x41e/0x700 mm/slub.c:5770 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] kernfs_fop_open+0x397/0xca0 fs/kernfs/file.c:641 do_dentry_open+0x953/0x13f0 fs/open.c:965 vfs_open+0x3b/0x340 fs/open.c:1097 do_open fs/namei.c:3975 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4134 do_filp_open+0x1fa/0x410 fs/namei.c:4161 do_sys_openat2+0x121/0x1c0 fs/open.c:1437 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+0x138/0x170 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 page last free pid 5200 tgid 5200 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2948 discard_slab mm/slub.c:3334 [inline] __put_partials+0x146/0x170 mm/slub.c:3880 put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3955 __slab_free+0x2b9/0x390 mm/slub.c:5933 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:349 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4982 [inline] slab_alloc_node mm/slub.c:5292 [inline] kmem_cache_alloc_noprof+0x37d/0x700 mm/slub.c:5299 getname_flags+0xb8/0x540 fs/namei.c:146 getname include/linux/fs.h:3006 [inline] do_sys_openat2+0xbc/0x1c0 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+0x138/0x170 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802fe17e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802fe17f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802fe17f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88802fe18000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802fe18080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 8b 0d 0b 02 1d 07 mov 0x71d020b(%rip),%ecx # 0x71d0211 6: f7 c1 ff ff ff 7f test $0x7fffffff,%ecx c: 74 23 je 0x31 e: 65 48 8b 0d eb 01 1d mov %gs:0x71d01eb(%rip),%rcx # 0x71d0201 15: 07 16: 48 3b 4c 24 08 cmp 0x8(%rsp),%rcx 1b: 0f 85 cc 00 00 00 jne 0xed 21: 48 83 c4 10 add $0x10,%rsp 25: 5b pop %rbx 26: 41 5e pop %r14 28: 41 5f pop %r15 * 2a: 5d pop %rbp <-- trapping instruction 2b: e9 91 cf 02 00 jmp 0x2cfc1 30: cc int3 31: 48 c7 04 24 00 00 00 movq $0x0,(%rsp) 38: 00 39: 9c pushf 3a: 8f 04 24 pop (%rsp) 3d: f7 .byte 0xf7 3e: 04 24 add $0x24,%al