================================================================== BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0xf94/0x1030 drivers/hid/hid-mcp2221.c:944 Read of size 1 at addr ffff888046c63fff by task syz.0.702/9752 CPU: 1 UID: 0 PID: 9752 Comm: syz.0.702 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+0xf94/0x1030 drivers/hid/hid-mcp2221.c:944 __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:__sanitizer_cov_trace_pc+0x56/0x70 kernel/kcov.c:222 Code: 00 f0 00 75 35 8b 82 3c 16 00 00 85 c0 74 2b 8b 82 18 16 00 00 83 f8 02 75 20 48 8b 8a 20 16 00 00 8b 92 1c 16 00 00 48 8b 01 <48> 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 c3 cc cc cc cc 0f RSP: 0018:ffffc90003a8f868 EFLAGS: 00000246 RAX: 000000000007ffff RBX: ffff8880582d5d80 RCX: ffffc9000dc37000 RDX: 0000000000080000 RSI: ffffffff8a3990cd RDI: 0000000000000005 RBP: 00000000ffffffff R08: 0000000000000005 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000000 R12: ffff8880582d62f0 R13: 0000000000000000 R14: 0000000000000000 R15: ffff888075214280 __unix_dgram_recvmsg+0x99d/0xc30 net/unix/af_unix.c:2675 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2700 sock_recvmsg_nosec net/socket.c:1065 [inline] ____sys_recvmsg+0x5f6/0x6b0 net/socket.c:2832 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2876 do_recvmmsg+0x2fe/0x750 net/socket.c:2971 __sys_recvmmsg net/socket.c:3045 [inline] __do_sys_recvmmsg net/socket.c:3068 [inline] __se_sys_recvmmsg net/socket.c:3061 [inline] __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3061 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: 0033:0x7faf3a38ebe9 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:00007faf3b19e038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007faf3a5b6090 RCX: 00007faf3a38ebe9 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000006 RBP: 00007faf3a411e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007faf3a5b6128 R14: 00007faf3a5b6090 R15: 00007ffdf4498bc8 Allocated by task 5514: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:356 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] kmem_cache_alloc_node_noprof+0x1d5/0x3b0 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] nlmsg_new include/net/netlink.h:1055 [inline] netlink_ack+0x15d/0xb80 net/netlink/af_netlink.c:2489 netlink_rcv_skb+0x332/0x420 net/netlink/af_netlink.c:2558 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5a7/0x870 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa95/0xc70 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 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5514: 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 skb_kfree_head net/core/skbuff.c:1045 [inline] skb_kfree_head net/core/skbuff.c:1042 [inline] skb_free_head+0x1b7/0x210 net/core/skbuff.c:1059 skb_release_data+0x795/0x9e0 net/core/skbuff.c:1086 skb_release_all net/core/skbuff.c:1151 [inline] __kfree_skb net/core/skbuff.c:1165 [inline] consume_skb net/core/skbuff.c:1397 [inline] consume_skb+0xbf/0x100 net/core/skbuff.c:1391 netlink_recvmsg+0x5b9/0xa90 net/netlink/af_netlink.c:1974 sock_recvmsg_nosec net/socket.c:1065 [inline] sock_recvmsg+0x1f9/0x250 net/socket.c:1087 ____sys_recvmsg+0x218/0x6b0 net/socket.c:2834 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2876 __sys_recvmsg+0x16a/0x220 net/socket.c:2909 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 The buggy address belongs to the object at ffff888046c63a80 which belongs to the cache skbuff_small_head of size 704 The buggy address is located 703 bytes to the right of allocated 704-byte region [ffff888046c63a80, ffff888046c63d40) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x46c60 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 ffff88801f2ddc80 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801f2ddc80 dead000000000122 0000000000000000 head: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea00011b1801 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 5514, tgid 5514 (dhcpcd), ts 363267546760, free_ts 336584433831 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+0xa95/0xc70 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 6007 tgid 6007 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 discard_slab mm/slub.c:2753 [inline] __put_partials+0x165/0x1c0 mm/slub.c:3218 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] kmem_cache_alloc_lru_noprof+0x1d0/0x3b0 mm/slub.c:4248 sock_alloc_inode+0x25/0x1c0 net/socket.c:309 alloc_inode+0x64/0x240 fs/inode.c:346 new_inode_pseudo include/linux/fs.h:3391 [inline] sock_alloc+0x40/0x280 net/socket.c:624 __sock_create+0xc1/0x8d0 net/socket.c:1553 rds_tcp_conn_path_connect+0x2d0/0x7f0 net/rds/tcp_connect.c:115 rds_connect_worker+0x1ac/0x2c0 net/rds/threads.c:176 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 Memory state around the buggy address: ffff888046c63e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888046c63f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888046c63f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888046c64000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888046c64080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 00 f0 add %dh,%al 2: 00 75 35 add %dh,0x35(%rbp) 5: 8b 82 3c 16 00 00 mov 0x163c(%rdx),%eax b: 85 c0 test %eax,%eax d: 74 2b je 0x3a f: 8b 82 18 16 00 00 mov 0x1618(%rdx),%eax 15: 83 f8 02 cmp $0x2,%eax 18: 75 20 jne 0x3a 1a: 48 8b 8a 20 16 00 00 mov 0x1620(%rdx),%rcx 21: 8b 92 1c 16 00 00 mov 0x161c(%rdx),%edx 27: 48 8b 01 mov (%rcx),%rax * 2a: 48 83 c0 01 add $0x1,%rax <-- trapping instruction 2e: 48 39 d0 cmp %rdx,%rax 31: 73 07 jae 0x3a 33: 48 89 01 mov %rax,(%rcx) 36: 48 89 34 c1 mov %rsi,(%rcx,%rax,8) 3a: c3 ret 3b: cc int3 3c: cc int3 3d: cc int3 3e: cc int3 3f: 0f .byte 0xf