================================================================== BUG: KASAN: use-after-free in __xfrm_state_insert+0x8af/0x1450 net/xfrm/xfrm_state.c:1743 Read of size 1 at addr ffff88805a953a70 by task syz.2.2838/16678 CPU: 0 UID: 0 PID: 16678 Comm: syz.2.2838 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __xfrm_state_insert+0x8af/0x1450 net/xfrm/xfrm_state.c:1743 xfrm_state_insert+0x54/0x60 net/xfrm/xfrm_state.c:1795 ipcomp6_tunnel_attach net/ipv6/ipcomp6.c:131 [inline] ipcomp6_init_state+0x655/0x900 net/ipv6/ipcomp6.c:163 __xfrm_init_state+0xa73/0x13f0 net/xfrm/xfrm_state.c:3188 xfrm_init_state+0x18/0xa0 net/xfrm/xfrm_state.c:3231 pfkey_msg2xfrm_state net/key/af_key.c:1286 [inline] pfkey_add+0x1d38/0x2e00 net/key/af_key.c:1504 pfkey_process net/key/af_key.c:2848 [inline] pfkey_sendmsg+0xbfe/0x1090 net/key/af_key.c:3699 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:729 ____sys_sendmsg+0x52d/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmmsg+0x227/0x430 net/socket.c:2757 __do_sys_sendmmsg net/socket.c:2784 [inline] __se_sys_sendmmsg net/socket.c:2781 [inline] __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2781 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2e0f98eec9 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:00007f2e108c3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f2e0fbe6090 RCX: 00007f2e0f98eec9 RDX: 000000000400008a RSI: 0000200000000180 RDI: 0000000000000004 RBP: 00007f2e0fa11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2e0fbe6128 R14: 00007f2e0fbe6090 R15: 00007ffe74fc7568 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5a953 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 14609, tgid 14608 (syz.0.2287), ts 330438241354, free_ts 378336026589 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2492 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2660 new_slab mm/slub.c:2714 [inline] ___slab_alloc+0xbeb/0x1420 mm/slub.c:3901 __slab_alloc mm/slub.c:3992 [inline] __slab_alloc_node mm/slub.c:4067 [inline] slab_alloc_node mm/slub.c:4228 [inline] kmem_cache_alloc_node_noprof+0x280/0x3c0 mm/slub.c:4292 kmalloc_reserve+0xbd/0x290 net/core/skbuff.c:579 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670 alloc_skb include/linux/skbuff.h:1377 [inline] alloc_uevent_skb+0x7d/0x230 lib/kobject_uevent.c:289 uevent_net_broadcast_tagged lib/kobject_uevent.c:352 [inline] kobject_uevent_net_broadcast+0x184/0x560 lib/kobject_uevent.c:413 kobject_uevent_env+0x55b/0x8c0 lib/kobject_uevent.c:608 rx_queue_add_kobject net/core/net-sysfs.c:1280 [inline] net_rx_queue_update_kobjects+0x3e5/0x740 net/core/net-sysfs.c:1322 register_queue_kobjects net/core/net-sysfs.c:2114 [inline] netdev_register_kobject+0x21f/0x310 net/core/net-sysfs.c:2362 register_netdevice+0x126c/0x1ae0 net/core/dev.c:11287 __ip_tunnel_create+0x3e7/0x560 net/ipv4/ip_tunnel.c:268 page last free pid 9802 tgid 9802 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 __slab_free+0x303/0x3c0 mm/slub.c:4606 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4191 [inline] slab_alloc_node mm/slub.c:4240 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4247 lsm_inode_alloc security/security.c:755 [inline] security_inode_alloc+0x39/0x330 security/security.c:1697 inode_init_always_gfp+0x9ed/0xdc0 fs/inode.c:306 inode_init_always include/linux/fs.h:3309 [inline] alloc_inode+0x82/0x1b0 fs/inode.c:353 new_inode_pseudo include/linux/fs.h:3392 [inline] sock_alloc net/socket.c:624 [inline] __sock_create+0x12d/0x9f0 net/socket.c:1553 rds_tcp_conn_path_connect+0x282/0x680 net/rds/tcp_connect.c:-1 rds_connect_worker+0x1d5/0x290 net/rds/threads.c:176 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 Memory state around the buggy address: ffff88805a953900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805a953980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88805a953a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88805a953a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805a953b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================