================================================================== BUG: KASAN: use-after-free in mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:948 Read of size 1 at addr ffff88804229ffff by task ktimers/1/29 CPU: 1 UID: 0 PID: 29 Comm: ktimers/1 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 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:948 __hid_input_report drivers/hid/hid-core.c:2139 [inline] hid_input_report+0x420/0x580 drivers/hid/hid-core.c:2166 hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x3b3/0x5e0 drivers/usb/core/hcd.c:1661 dummy_timer+0x8a6/0x4710 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x54c/0xd10 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x1a3/0x2e0 kernel/time/hrtimer.c:1858 handle_softirqs+0x1de/0x640 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] run_ktimerd+0x69/0x100 kernel/softirq.c:1138 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88804229fdc0 pfn:0x4229f flags: 0x80000000000000(node=0|zone=1) raw: 0080000000000000 dead000000000100 dead000000000122 0000000000000000 raw: ffff88804229fdc0 00000000000c0000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 8797, tgid 8795 (syz.3.1048), ts 192426180161, free_ts 203767662158 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x228/0x280 mm/page_alloc.c:1884 prep_new_page mm/page_alloc.c:1892 [inline] get_page_from_freelist+0x28bb/0x2950 mm/page_alloc.c:3945 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5240 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3a0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xaf8/0x13d0 mm/slub.c:4656 __slab_alloc+0xc5/0x1f0 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] kmem_cache_alloc_node_noprof+0x1ad/0x6d0 mm/slub.c:5315 __alloc_skb+0x1d7/0x390 net/core/skbuff.c:679 alloc_skb include/linux/skbuff.h:1383 [inline] alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6715 sock_alloc_send_pskb+0x884/0x9a0 net/core/sock.c:2995 sock_alloc_send_skb include/net/sock.h:1885 [inline] llc_ui_sendmsg+0x487/0xea0 net/llc/af_llc.c:970 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 sock_sendmsg+0x192/0x290 net/socket.c:765 splice_to_socket+0xae5/0x11f0 fs/splice.c:886 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x104/0x160 fs/splice.c:1161 page last free pid 5888 tgid 5888 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0xfc1/0x1130 mm/page_alloc.c:2973 discard_slab mm/slub.c:3346 [inline] __put_partials+0x149/0x170 mm/slub.c:3886 __slab_free+0x2af/0x330 mm/slub.c:5956 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:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] __kmalloc_cache_noprof+0x188/0x6b0 mm/slub.c:5775 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] device_create_groups_vargs drivers/base/core.c:4353 [inline] device_create+0x13d/0x300 drivers/base/core.c:4410 hidraw_connect+0x219/0x430 drivers/hid/hidraw.c:628 hid_connect+0x5bf/0x19d0 drivers/hid/hid-core.c:2269 hid_hw_start+0xa8/0x120 drivers/hid/hid-core.c:2379 nzxt_smart2_hid_probe+0x13b/0x3b0 drivers/hwmon/nzxt-smart2.c:747 __hid_device_probe drivers/hid/hid-core.c:2775 [inline] hid_device_probe+0x416/0x7a0 drivers/hid/hid-core.c:2812 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0xac0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:801 driver_probe_device+0x4f/0x240 drivers/base/dd.c:831 Memory state around the buggy address: ffff88804229fe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88804229ff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88804229ff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880422a0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880422a0080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================