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BUG: KASAN: slab-use-after-free in hlist_add_head include/linux/list.h:1026 [inline]
BUG: KASAN: slab-use-after-free in udp_tunnel_update_gro_lookup+0xfe/0x2c0 net/ipv4/udp_offload.c:60
Write of size 8 at addr ffff8880355f35b0 by task syz.2.1913/12632

CPU: 1 UID: 0 PID: 12632 Comm: syz.2.1913 Not tainted 6.14.0-rc7-syzkaller-01431-gbfc17c165835 #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_add_head include/linux/list.h:1026 [inline]
 udp_tunnel_update_gro_lookup+0xfe/0x2c0 net/ipv4/udp_offload.c:60
 rxrpc_open_socket net/rxrpc/local_object.c:197 [inline]
 rxrpc_lookup_local+0xea5/0x1890 net/rxrpc/local_object.c:293
 rxrpc_sendmsg+0x323/0x5f0 net/rxrpc/af_rxrpc.c:608
 sock_sendmsg_nosec net/socket.c:709 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:724
 ____sys_sendmsg+0x53a/0x860 net/socket.c:2564
 ___sys_sendmsg net/socket.c:2618 [inline]
 __sys_sendmmsg+0x36a/0x720 net/socket.c:2707
 __do_sys_sendmmsg net/socket.c:2734 [inline]
 __se_sys_sendmmsg net/socket.c:2731 [inline]
 __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2731
 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: 0033:0x7f36f498d169
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:00007f36f57cf038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f36f4ba5fa0 RCX: 00007f36f498d169
RDX: 0000000000000001 RSI: 0000200000000180 RDI: 0000000000000003
RBP: 00007f36f4a0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 61acbc565664f7c8 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f36f4ba5fa0 R15: 00007ffc2d9ae238
 </TASK>

Allocated by task 12491:
 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
 inet_create+0x648/0xea0 net/ipv4/af_inet.c:326
 __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 12490:
 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
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880355f2e80
 which belongs to the cache UDP of size 1856
The buggy address is located 1840 bytes inside of
 freed 1856-byte region [ffff8880355f2e80, ffff8880355f35c0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x355f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888033dd0201
ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801bbac3c0 ffffea00017a5600 0000000000000003
raw: 0000000000000000 0000000080100010 00000000f5000000 ffff888033dd0201
head: 00fff00000000040 ffff88801bbac3c0 ffffea00017a5600 0000000000000003
head: 0000000000000000 0000000080100010 00000000f5000000 ffff888033dd0201
head: 00fff00000000003 ffffea0000d57c01 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 6035, tgid 6034 (syz.4.35), ts 83734880165, free_ts 83652544899
 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
 inet_create+0x648/0xea0 net/ipv4/af_inet.c:326
 __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
page last free pid 6033 tgid 6033 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]
 __do_kmalloc_node mm/slub.c:4293 [inline]
 __kmalloc_node_noprof+0x23c/0x4d0 mm/slub.c:4300
 kmalloc_array_node_noprof include/linux/slab.h:1018 [inline]
 alloc_slab_obj_exts+0x3a/0xa0 mm/slub.c:1964
 __memcg_slab_post_alloc_hook+0x319/0x7e0 mm/memcontrol.c:3004
 memcg_slab_post_alloc_hook mm/slub.c:2152 [inline]
 slab_post_alloc_hook mm/slub.c:4125 [inline]
 slab_alloc_node mm/slub.c:4164 [inline]
 kmem_cache_alloc_noprof+0x287/0x380 mm/slub.c:4171
 anon_vma_alloc mm/rmap.c:94 [inline]
 __anon_vma_prepare+0x117/0x4a0 mm/rmap.c:202
 __vmf_anon_prepare mm/memory.c:3401 [inline]
 vmf_anon_prepare mm/internal.h:372 [inline]
 do_anonymous_page mm/memory.c:4887 [inline]
 do_pte_missing mm/memory.c:4057 [inline]
 handle_pte_fault mm/memory.c:5888 [inline]
 __handle_mm_fault+0x5f7d/0x6ef0 mm/memory.c:6031
 handle_mm_fault+0x3e5/0x8d0 mm/memory.c:6200
 do_user_addr_fault arch/x86/mm/fault.c:1337 [inline]
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x459/0x8b0 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

Memory state around the buggy address:
 ffff8880355f3480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880355f3500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880355f3580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                                     ^
 ffff8880355f3600: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
 ffff8880355f3680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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