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BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:980 [inline]
BUG: KASAN: slab-use-after-free in hlist_del_init include/linux/list.h:1008 [inline]
BUG: KASAN: slab-use-after-free in udp_tunnel_update_gro_lookup+0x169/0x2c0 net/ipv4/udp_offload.c:62
Write of size 8 at addr ffff888029986d28 by task syz.1.354/7006

CPU: 1 UID: 0 PID: 7006 Comm: syz.1.354 Not tainted 6.14.0-rc6-syzkaller-01279-gaedfbe251e1c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0x16e/0x5b0 mm/kasan/report.c:521
 kasan_report+0x143/0x180 mm/kasan/report.c:634
 __hlist_del include/linux/list.h:980 [inline]
 hlist_del_init include/linux/list.h:1008 [inline]
 udp_tunnel_update_gro_lookup+0x169/0x2c0 net/ipv4/udp_offload.c:62
 sk_common_release+0x71/0x2e0 net/core/sock.c:3892
 inet_release+0x17d/0x200 net/ipv4/af_inet.c:435
 __sock_release net/socket.c:647 [inline]
 sock_close+0xbc/0x240 net/socket.c:1389
 __fput+0x3e9/0x9f0 fs/file_table.c:464
 task_work_run+0x24f/0x310 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xa2a/0x28e0 kernel/exit.c:938
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096
 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6d8a78d169
Code: Unable to access opcode bytes at 0x7f6d8a78d13f.
RSP: 002b:00007fffc0d2fd78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000000000000b RCX: 00007f6d8a78d169
RDX: 00007f6d8a744777 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 0000000000000003 R08: 00007fffc0d301f7 R09: 000000000000000b
R10: 00007f6d8a9a5fa0 R11: 0000000000000246 R12: 00007f6d8a9a624c
R13: 00007f6d8a9a6240 R14: 0000000000000091 R15: 0000000000000003
 </TASK>

Allocated by task 7007:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4115 [inline]
 slab_alloc_node mm/slub.c:4164 [inline]
 kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4171
 sk_prot_alloc+0x58/0x210 net/core/sock.c:2190
 sk_alloc+0x3e/0x370 net/core/sock.c:2249
 inet6_create+0x6ce/0x10f0 net/ipv6/af_inet6.c:193
 __sock_create+0x4c0/0xa30 net/socket.c:1539
 sock_create net/socket.c:1597 [inline]
 __sys_socket_create net/socket.c:1634 [inline]
 __sys_socket+0x150/0x3c0 net/socket.c:1681
 __do_sys_socket net/socket.c:1695 [inline]
 __se_sys_socket net/socket.c:1693 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1693
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 7006:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4609 [inline]
 kmem_cache_free+0x195/0x410 mm/slub.c:4711
 sk_prot_free net/core/sock.c:2230 [inline]
 __sk_destruct+0x4fd/0x690 net/core/sock.c:2327
 inet_release+0x17d/0x200 net/ipv4/af_inet.c:435
 __sock_release net/socket.c:647 [inline]
 sock_close+0xbc/0x240 net/socket.c:1389
 __fput+0x3e9/0x9f0 fs/file_table.c:464
 task_work_run+0x24f/0x310 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xa2a/0x28e0 kernel/exit.c:938
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096
 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888029986600
 which belongs to the cache UDPv6 of size 2048
The buggy address is located 1832 bytes inside of
 freed 2048-byte region [ffff888029986600, ffff888029986e00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888029982200 pfn:0x29980
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff8880750b9f01
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88814c1d0a00 dead000000000122 0000000000000000
raw: ffff888029982200 00000000800f000d 00000000f5000000 ffff8880750b9f01
head: 00fff00000000040 ffff88814c1d0a00 dead000000000122 0000000000000000
head: ffff888029982200 00000000800f000d 00000000f5000000 ffff8880750b9f01
head: 00fff00000000003 ffffea0000a66001 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6394, tgid 6391 (syz.0.149), ts 98427101671, free_ts 98396093819
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551
 prep_new_page mm/page_alloc.c:1559 [inline]
 get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477
 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4740
 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270
 alloc_slab_page mm/slub.c:2423 [inline]
 allocate_slab+0x8f/0x3a0 mm/slub.c:2587
 new_slab mm/slub.c:2640 [inline]
 ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826
 __slab_alloc+0x58/0xa0 mm/slub.c:3916
 __slab_alloc_node mm/slub.c:3991 [inline]
 slab_alloc_node mm/slub.c:4152 [inline]
 kmem_cache_alloc_noprof+0x268/0x380 mm/slub.c:4171
 sk_prot_alloc+0x58/0x210 net/core/sock.c:2190
 sk_alloc+0x3e/0x370 net/core/sock.c:2249
 inet6_create+0x6ce/0x10f0 net/ipv6/af_inet6.c:193
 __sock_create+0x4c0/0xa30 net/socket.c:1539
 udp_sock_create6+0xe5/0x820 net/ipv6/ip6_udp_tunnel.c:24
 udp_sock_create include/net/udp_tunnel.h:62 [inline]
 rxrpc_open_socket net/rxrpc/local_object.c:187 [inline]
 rxrpc_lookup_local+0xd8f/0x1890 net/rxrpc/local_object.c:293
 rxrpc_bind+0x181/0x430 net/rxrpc/af_rxrpc.c:150
 kernel_bind+0x10c/0x170 net/socket.c:3526
page last free pid 6394 tgid 6391 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660
 discard_slab mm/slub.c:2684 [inline]
 __put_partials+0x160/0x1c0 mm/slub.c:3153
 put_cpu_partial+0x17c/0x250 mm/slub.c:3228
 __slab_free+0x290/0x380 mm/slub.c:4479
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4115 [inline]
 slab_alloc_node mm/slub.c:4164 [inline]
 __kmalloc_cache_noprof+0x1d9/0x390 mm/slub.c:4320
 kmalloc_noprof include/linux/slab.h:901 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 kset_create lib/kobject.c:965 [inline]
 kset_create_and_add+0x5b/0x170 lib/kobject.c:1008
 register_queue_kobjects net/core/net-sysfs.c:2082 [inline]
 netdev_register_kobject+0x181/0x2f0 net/core/net-sysfs.c:2335
 register_netdevice+0x12c3/0x1b70 net/core/dev.c:10992
 __ip_tunnel_create+0x3be/0x520 net/ipv4/ip_tunnel.c:268
 ip_tunnel_init_net+0x2aa/0x7e0 net/ipv4/ip_tunnel.c:1161
 ops_init+0x349/0x5b0 net/core/net_namespace.c:138
 setup_net+0x287/0x9e0 net/core/net_namespace.c:362
 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516

Memory state around the buggy address:
 ffff888029986c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888029986c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888029986d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888029986d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888029986e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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