================================================================== 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 ffff888029235c70 by task syz.1.508/7936 CPU: 0 UID: 0 PID: 7936 Comm: syz.1.508 Not tainted 6.14.0-rc7-syzkaller-01413-gd9917c7d533c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __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 wg_socket_init+0x78f/0xea0 drivers/net/wireguard/socket.c:393 set_port drivers/net/wireguard/netlink.c:326 [inline] wg_set_device+0x710/0x20d0 drivers/net/wireguard/netlink.c:534 genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0xb1f/0xec0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 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: 0033:0x7f53b9f8d169 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:00007f53bad73038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f53ba1a6080 RCX: 00007f53b9f8d169 RDX: 0000000000000000 RSI: 0000200000001040 RDI: 0000000000000008 RBP: 00007f53ba00e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f53ba1a6080 R15: 00007ffe64d08a08 Allocated by task 7863: 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 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 setup_net+0x287/0x9e0 net/core/net_namespace.c:362 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 ksys_unshare+0x57d/0xa70 kernel/fork.c:3342 __do_sys_unshare kernel/fork.c:3413 [inline] __se_sys_unshare kernel/fork.c:3411 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3411 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 7863: 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_release+0x82/0x150 net/socket.c:675 ops_exit_list net/core/net_namespace.c:172 [inline] setup_net+0x794/0x9e0 net/core/net_namespace.c:394 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 ksys_unshare+0x57d/0xa70 kernel/fork.c:3342 __do_sys_unshare kernel/fork.c:3413 [inline] __se_sys_unshare kernel/fork.c:3411 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3411 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 ffff888029235540 which belongs to the cache UDP of size 1856 The buggy address is located 1840 bytes inside of freed 1856-byte region [ffff888029235540, ffff888029235c80) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888029231f00 pfn:0x29230 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888033a85001 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88814368e640 dead000000000122 0000000000000000 raw: ffff888029231f00 000000008010000d 00000000f5000000 ffff888033a85001 head: 00fff00000000040 ffff88814368e640 dead000000000122 0000000000000000 head: ffff888029231f00 000000008010000d 00000000f5000000 ffff888033a85001 head: 00fff00000000003 ffffea0000a48c01 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 5835, tgid 5835 (syz-executor), ts 79264934468, free_ts 79121172894 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 udp_sock_create4+0xda/0x670 net/ipv4/udp_tunnel_core.c:18 udp_sock_create include/net/udp_tunnel.h:59 [inline] geneve_create_sock drivers/net/geneve.c:487 [inline] geneve_socket_create drivers/net/geneve.c:600 [inline] geneve_sock_add+0x469/0xc40 drivers/net/geneve.c:687 geneve_open+0xe3/0x160 drivers/net/geneve.c:729 __dev_open+0x45a/0x8a0 net/core/dev.c:1622 page last free pid 5209 tgid 5209 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_noprof+0x236/0x4c0 mm/slub.c:4306 kmalloc_noprof include/linux/slab.h:905 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x2c0/0x610 security/tomoyo/file.c:822 security_inode_getattr+0x130/0x330 security/security.c:2377 vfs_getattr fs/stat.c:243 [inline] vfs_fstat fs/stat.c:265 [inline] vfs_fstatat+0xa3/0x150 fs/stat.c:366 __do_sys_newfstatat fs/stat.c:532 [inline] __se_sys_newfstatat fs/stat.c:526 [inline] __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:526 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 Memory state around the buggy address: ffff888029235b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888029235b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888029235c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888029235c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888029235d00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================