================================================================== BUG: KASAN: slab-out-of-bounds in find_endpoint drivers/usb/gadget/udc/dummy_hcd.c:1617 [inline] BUG: KASAN: slab-out-of-bounds in dummy_timer+0xca7/0x34e0 drivers/usb/gadget/udc/dummy_hcd.c:1888 Read of size 1 at addr ffff8880607e5532 by task syz.0.3124/16712 CPU: 1 PID: 16712 Comm: syz.0.3124 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 find_endpoint drivers/usb/gadget/udc/dummy_hcd.c:1617 [inline] dummy_timer+0xca7/0x34e0 drivers/usb/gadget/udc/dummy_hcd.c:1888 __run_hrtimer kernel/time/hrtimer.c:1754 [inline] __hrtimer_run_queues+0x525/0xc10 kernel/time/hrtimer.c:1818 hrtimer_run_softirq+0x177/0x290 kernel/time/hrtimer.c:1835 handle_softirqs+0x27d/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0033:0x7ff53b4517c3 Code: 00 00 00 0f 1f 40 00 41 89 fb 44 8d 56 04 4c 8d 0d 52 08 3c 00 89 f0 4c 8d 05 49 e8 3b 00 89 c2 81 e2 ff 1f 00 00 49 8b 0c d1 <48> 39 f1 74 28 48 85 c9 74 29 45 38 1c 10 75 23 83 c0 01 44 39 d0 RSP: 002b:00007ffc84439a18 EFLAGS: 00000202 RAX: 0000000081ef8ab5 RBX: ffffffff81ef8ab5 RCX: ffffffff81796ab5 RDX: 0000000000000ab5 RSI: ffffffff81ef8ab5 RDI: 0000000000000002 RBP: 0000000000000000 R08: 00007ff53b810000 R09: 00007ff53b812000 R10: 0000000081ef8ab9 R11: 0000000000000002 R12: 00007ff53b826038 R13: 0000000000001012 R14: ffffffff81ef8061 R15: 00007ff53c355720 Allocated by task 12843: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] device_private_init drivers/base/core.c:3530 [inline] device_add+0xb6/0xc40 drivers/base/core.c:3581 netdev_register_kobject+0x188/0x320 net/core/net-sysfs.c:2042 register_netdevice+0x12aa/0x1ba0 net/core/dev.c:10318 veth_newlink+0x5cb/0xc70 drivers/net/veth.c:1877 rtnl_newlink_create net/core/rtnetlink.c:3529 [inline] __rtnl_newlink net/core/rtnetlink.c:3749 [inline] rtnl_newlink+0x15a0/0x2170 net/core/rtnetlink.c:3762 rtnetlink_rcv_msg+0x843/0xf90 net/core/rtnetlink.c:6484 netlink_rcv_skb+0x235/0x4c0 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x7b1/0x930 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1899 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x4a9/0x6b0 net/socket.c:2201 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x900 kernel/rcu/tree.c:2837 fib6_info_release include/net/ip6_fib.h:349 [inline] ip6_route_info_create+0xa0d/0x1260 net/ipv6/route.c:3887 ip6_route_add+0x28/0x160 net/ipv6/route.c:3901 addrconf_prefix_route+0x24d/0x330 net/ipv6/addrconf.c:2470 inet6_addr_add+0x62f/0xb30 net/ipv6/addrconf.c:3064 inet6_rtm_newaddr+0x6fd/0x9d0 net/ipv6/addrconf.c:5043 rtnetlink_rcv_msg+0x843/0xf90 net/core/rtnetlink.c:6484 netlink_rcv_skb+0x235/0x4c0 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x7b1/0x930 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1899 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x4a9/0x6b0 net/socket.c:2201 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff8880607e5400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 34 bytes to the right of allocated 272-byte region [ffff8880607e5400, ffff8880607e5510) The buggy address belongs to the physical page: page:ffffea000181f900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x607e4 head:ffffea000181f900 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017c41c80 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 11, tgid 11 (kworker/u4:0), ts 86262827127, free_ts 29886264282 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582 prep_new_page mm/page_alloc.c:1589 [inline] get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501 alloc_slab_page+0x5d/0x180 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5c/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x11f/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa7/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x455/0x1260 net/ipv6/route.c:3805 ip6_route_add+0x28/0x160 net/ipv6/route.c:3901 addrconf_prefix_route net/ipv6/addrconf.c:2470 [inline] addrconf_add_linklocal+0x44d/0x6d0 net/ipv6/addrconf.c:3316 addrconf_addr_gen+0x50e/0x620 net/ipv6/addrconf.c:3445 addrconf_dev_config net/ipv6/addrconf.c:3490 [inline] addrconf_init_auto_addrs+0x720/0xac0 net/ipv6/addrconf.c:3569 addrconf_notify+0xb62/0x1010 net/ipv6/addrconf.c:3742 notifier_call_chain+0x18f/0x380 kernel/notifier.c:93 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1182 [inline] free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459 free_contig_range+0xa1/0x150 mm/page_alloc.c:6421 destroy_args+0x7d/0x840 mm/debug_vm_pgtable.c:1015 debug_vm_pgtable+0x411/0x440 mm/debug_vm_pgtable.c:1400 do_one_initcall+0x242/0x790 init/main.c:1210 do_initcall_level+0x13d/0x1f0 init/main.c:1272 do_initcalls+0x69/0xd0 init/main.c:1288 kernel_init_freeable+0x3d9/0x560 init/main.c:1525 kernel_init+0x1d/0x1c0 init/main.c:1415 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Memory state around the buggy address: ffff8880607e5400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880607e5480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880607e5500: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880607e5580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880607e5600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================