syzbot

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BUG: KASAN: slab-use-after-free in udp_tunnel_update_gro_lookup+0x23c/0x2c0 net/ipv4/udp_offload.c:65
Read of size 8 at addr ffff88801bf7ebe8 by task syz.0.709/8655

CPU: 0 UID: 0 PID: 8655 Comm: syz.0.709 Not tainted 6.14.0-rc6-syzkaller-01366-g6855b9be9cf7 #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
 udp_tunnel_update_gro_lookup+0x23c/0x2c0 net/ipv4/udp_offload.c:65
 sk_common_release+0x71/0x2e0 net/core/sock.c:3896
 inet_release+0x17d/0x200 net/ipv4/af_inet.c:435
 __sock_release net/socket.c:647 [inline]
 sock_release+0x82/0x150 net/socket.c:675
 sock_free drivers/net/wireguard/socket.c:339 [inline]
 wg_socket_reinit+0x215/0x380 drivers/net/wireguard/socket.c:435
 wg_stop+0x59f/0x600 drivers/net/wireguard/device.c:133
 __dev_close_many+0x3a6/0x700 net/core/dev.c:1695
 __dev_close net/core/dev.c:1707 [inline]
 __dev_change_flags+0x30e/0x6f0 net/core/dev.c:9336
 netif_change_flags+0x8b/0x1a0 net/core/dev.c:9401
 do_setlink+0xd94/0x41d0 net/core/rtnetlink.c:3149
 rtnl_group_changelink net/core/rtnetlink.c:3780 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3934 [inline]
 rtnl_newlink+0x141c/0x1d90 net/core/rtnetlink.c:4062
 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6952
 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
 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_sendmsg+0x269/0x350 net/socket.c:2650
 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: 0033:0x7f45c138d169
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:00007f45c2148038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f45c15a6080 RCX: 00007f45c138d169
RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000008
RBP: 00007f45c140e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f45c15a6080 R15: 00007ffc0729b1e8
 </TASK>

Allocated by task 8651:
 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
 udp_sock_create4+0xda/0x670 net/ipv4/udp_tunnel_core.c:18
 udp_sock_create include/net/udp_tunnel.h:59 [inline]
 wg_socket_init+0x6c0/0xea0 drivers/net/wireguard/socket.c:387
 wg_open+0x255/0x420 drivers/net/wireguard/device.c:51
 __dev_open+0x45a/0x8a0 net/core/dev.c:1622
 __dev_change_flags+0x1e2/0x6f0 net/core/dev.c:9338
 rtnl_configure_link net/core/rtnetlink.c:3585 [inline]
 rtnl_newlink_create+0x5ea/0xbd0 net/core/rtnetlink.c:3840
 __rtnl_newlink net/core/rtnetlink.c:3947 [inline]
 rtnl_newlink+0x167a/0x1d90 net/core/rtnetlink.c:4062
 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6952
 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
 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_sendmsg+0x269/0x350 net/socket.c:2650
 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 13:
 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
 rcu_do_batch kernel/rcu/tree.c:2546 [inline]
 rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2802
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
 __do_softirq kernel/softirq.c:595 [inline]
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xaa/0xc0 mm/kasan/generic.c:548
 __call_rcu_common kernel/rcu/tree.c:3065 [inline]
 call_rcu+0x168/0xac0 kernel/rcu/tree.c:3172
 inet_release+0x17d/0x200 net/ipv4/af_inet.c:435
 __sock_release net/socket.c:647 [inline]
 sock_release+0x82/0x150 net/socket.c:675
 sock_free drivers/net/wireguard/socket.c:339 [inline]
 wg_socket_reinit+0x215/0x380 drivers/net/wireguard/socket.c:435
 wg_stop+0x59f/0x600 drivers/net/wireguard/device.c:133
 __dev_close_many+0x3a6/0x700 net/core/dev.c:1695
 dev_close_many+0x24e/0x4c0 net/core/dev.c:1720
 unregister_netdevice_many_notify+0x629/0x24f0 net/core/dev.c:11910
 rtnl_newlink_create+0x890/0xbd0 net/core/rtnetlink.c:3858
 __rtnl_newlink net/core/rtnetlink.c:3947 [inline]
 rtnl_newlink+0x167a/0x1d90 net/core/rtnetlink.c:4062
 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6952
 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
 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_sendmsg+0x269/0x350 net/socket.c:2650
 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 ffff88801bf7e4c0
 which belongs to the cache UDP of size 1856
The buggy address is located 1832 bytes inside of
 freed 1856-byte region [ffff88801bf7e4c0, ffff88801bf7ec00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1bf78
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88807d2fa301
anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff8880202e1a00 0000000000000000 0000000000000001
raw: 0000000000000000 0000000080100010 00000000f5000000 ffff88807d2fa301
head: 00fff00000000040 ffff8880202e1a00 0000000000000000 0000000000000001
head: 0000000000000000 0000000080100010 00000000f5000000 ffff88807d2fa301
head: 00fff00000000003 ffffea00006fde01 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 1, tgid 1 (swapper/0), ts 4179863706, free_ts 0
 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
 inet_ctl_sock_create+0xc2/0x250 net/ipv4/af_inet.c:1637
 igmp_net_init+0xbb/0x150 net/ipv4/igmp.c:3125
 ops_init+0x349/0x5b0 net/core/net_namespace.c:138
 __register_pernet_operations net/core/net_namespace.c:1272 [inline]
 register_pernet_operations+0x30d/0x630 net/core/net_namespace.c:1348
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88801bf7ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801bf7eb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88801bf7eb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff88801bf7ec00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88801bf7ec80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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