================================================================== BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:980 [inline] BUG: KASAN: slab-use-after-free in hlist_del_rcu include/linux/rculist.h:513 [inline] BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x454/0x800 net/xfrm/xfrm_state.c:753 Write of size 8 at addr ffff88807893d828 by task kworker/u4:9/2951 CPU: 0 PID: 2951 Comm: kworker/u4:9 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: netns cleanup_net Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x220 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 __hlist_del include/linux/list.h:980 [inline] hlist_del_rcu include/linux/rculist.h:513 [inline] __xfrm_state_delete+0x454/0x800 net/xfrm/xfrm_state.c:753 xfrm_state_delete net/xfrm/xfrm_state.c:776 [inline] xfrm_state_flush+0x454/0x830 net/xfrm/xfrm_state.c:859 xfrm6_tunnel_net_exit+0x46/0x100 net/ipv6/xfrm6_tunnel.c:338 ops_exit_list net/core/net_namespace.c:173 [inline] cleanup_net+0x6f4/0xb90 net/core/net_namespace.c:652 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Allocated by task 14634: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3493 [inline] __kmem_cache_alloc_lru mm/slub.c:3500 [inline] kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3509 kmem_cache_zalloc include/linux/slab.h:711 [inline] xfrm_state_alloc+0x22/0x2a0 net/xfrm/xfrm_state.c:661 __find_acq_core+0x7d8/0x19d0 net/xfrm/xfrm_state.c:1598 xfrm_find_acq+0x6a/0x90 net/xfrm/xfrm_state.c:2070 xfrm_alloc_userspi+0x57a/0xa90 net/xfrm/xfrm_user.c:1613 xfrm_user_rcv_msg+0x596/0x870 net/xfrm/xfrm_user.c:3169 netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2545 xfrm_netlink_rcv+0x79/0x90 net/xfrm/xfrm_user.c:3191 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8c1/0xbe0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5bf/0x950 net/socket.c:2595 ___sys_sendmsg+0x220/0x290 net/socket.c:2649 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2687 [inline] __se_sys_sendmsg+0x1a5/0x270 net/socket.c:2685 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 2951: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] kmem_cache_free+0xf8/0x280 mm/slub.c:3838 __xfrm_state_destroy net/xfrm/xfrm_state.c:729 [inline] xfrm_state_put_sync include/net/xfrm.h:828 [inline] xfrm_state_flush+0x50e/0x830 net/xfrm/xfrm_state.c:863 xfrm6_tunnel_net_exit+0x46/0x100 net/ipv6/xfrm6_tunnel.c:338 ops_exit_list net/core/net_namespace.c:173 [inline] cleanup_net+0x6f4/0xb90 net/core/net_namespace.c:652 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88807893d800 which belongs to the cache xfrm_state of size 848 The buggy address is located 40 bytes inside of freed 848-byte region [ffff88807893d800, ffff88807893db50) The buggy address belongs to the physical page: page:ffffea0001e24f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7893c head:ffffea0001e24f00 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017ef2dc0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 12323, tgid 12322 (syz.0.3062), ts 336327632154, free_ts 328668073386 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1876 allocate_slab mm/slub.c:2023 [inline] new_slab+0x87/0x2e0 mm/slub.c:2076 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230 __slab_alloc mm/slub.c:3329 [inline] __slab_alloc_node mm/slub.c:3382 [inline] slab_alloc_node mm/slub.c:3475 [inline] slab_alloc mm/slub.c:3493 [inline] __kmem_cache_alloc_lru mm/slub.c:3500 [inline] kmem_cache_alloc+0x1b7/0x2e0 mm/slub.c:3509 kmem_cache_zalloc include/linux/slab.h:711 [inline] xfrm_state_alloc+0x22/0x2a0 net/xfrm/xfrm_state.c:661 __find_acq_core+0x7d8/0x19d0 net/xfrm/xfrm_state.c:1598 xfrm_find_acq+0x6a/0x90 net/xfrm/xfrm_state.c:2070 xfrm_alloc_userspi+0x57a/0xa90 net/xfrm/xfrm_user.c:1613 xfrm_user_rcv_msg+0x596/0x870 net/xfrm/xfrm_user.c:3169 netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2545 xfrm_netlink_rcv+0x79/0x90 net/xfrm/xfrm_user.c:3191 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8c1/0xbe0 net/netlink/af_netlink.c:1894 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2122 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2662 put_cpu_partial+0x17c/0x250 mm/slub.c:2738 __slab_free+0x31d/0x410 mm/slub.c:3686 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3493 [inline] __kmem_cache_alloc_lru mm/slub.c:3500 [inline] kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3509 getname_flags+0xbb/0x500 fs/namei.c:140 vfs_fstatat+0x111/0x1b0 fs/stat.c:298 __do_sys_newfstatat fs/stat.c:463 [inline] __se_sys_newfstatat fs/stat.c:457 [inline] __x64_sys_newfstatat+0x117/0x190 fs/stat.c:457 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88807893d700: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc ffff88807893d780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807893d800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807893d880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807893d900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================