================================================================== BUG: KASAN: slab-use-after-free in __xfrm_state_insert+0x8af/0x1450 net/xfrm/xfrm_state.c:1743 Read of size 1 at addr ffff8880574afeb0 by task syz.2.1351/11119 CPU: 1 UID: 0 PID: 11119 Comm: syz.2.1351 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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: 0033:0x7f2dcc58ebe9 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:00007f2dca7f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f2dcc7b5fa0 RCX: 00007f2dcc58ebe9 RDX: 000000000400008a RSI: 0000200000000180 RDI: 0000000000000009 RBP: 00007f2dcc611e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2dcc7b6038 R14: 00007f2dcc7b5fa0 R15: 00007ffe4f7c9e58 Allocated by task 6379: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236 xfrm_state_alloc+0x24/0x2f0 net/xfrm/xfrm_state.c:733 __find_acq_core+0x8a7/0x1c00 net/xfrm/xfrm_state.c:1833 xfrm_find_acq+0x78/0xa0 net/xfrm/xfrm_state.c:2353 xfrm_alloc_userspi+0x6b3/0xc90 net/xfrm/xfrm_user.c:1863 xfrm_user_rcv_msg+0x7a0/0xab0 net/xfrm/xfrm_user.c:3501 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552 xfrm_netlink_rcv+0x79/0x90 net/xfrm/xfrm_user.c:3523 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 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 Freed by task 5972: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4782 xfrm_state_free net/xfrm/xfrm_state.c:591 [inline] xfrm_state_gc_destroy net/xfrm/xfrm_state.c:618 [inline] xfrm_state_gc_task+0x52d/0x6b0 net/xfrm/xfrm_state.c:634 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+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff8880574afb80 which belongs to the cache xfrm_state of size 928 The buggy address is located 816 bytes inside of freed 928-byte region [ffff8880574afb80, ffff8880574aff20) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880574afb80 pfn:0x574ac head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff888142aa1c80 0000000000000000 0000000000000001 raw: ffff8880574afb80 00000000000f0001 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff888142aa1c80 0000000000000000 0000000000000001 head: ffff8880574afb80 00000000000f0001 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea00015d2b01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 6100, tgid 6098 (syz.1.32), ts 80472449405, free_ts 27397372658 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:2487 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4236 xfrm_state_alloc+0x24/0x2f0 net/xfrm/xfrm_state.c:733 xfrm_state_find+0x37d4/0x5400 net/xfrm/xfrm_state.c:1513 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2522 [inline] xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:2573 [inline] xfrm_resolve_and_create_bundle+0x768/0x2f80 net/xfrm/xfrm_policy.c:2871 xfrm_bundle_lookup net/xfrm/xfrm_policy.c:3106 [inline] xfrm_lookup_with_ifid+0x58a/0x1a70 net/xfrm/xfrm_policy.c:3237 xfrm_lookup net/xfrm/xfrm_policy.c:3336 [inline] xfrm_lookup_route+0x3c/0x1c0 net/xfrm/xfrm_policy.c:3347 ip6_datagram_dst_update+0x75c/0xcb0 net/ipv6/datagram.c:96 __ip6_datagram_connect+0xbd1/0x1150 net/ipv6/datagram.c:255 ip6_datagram_connect net/ipv6/datagram.c:279 [inline] ip6_datagram_connect_v6_only+0x63/0xa0 net/ipv6/datagram.c:291 __sys_connect_file net/socket.c:2086 [inline] __sys_connect+0x316/0x440 net/socket.c:2105 page last free pid 1 tgid 1 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 __free_pages mm/page_alloc.c:5260 [inline] free_contig_range+0x1bd/0x4a0 mm/page_alloc.c:7091 destroy_args+0x64/0x4a0 mm/debug_vm_pgtable.c:958 debug_vm_pgtable+0x39f/0x3b0 mm/debug_vm_pgtable.c:1340 do_one_initcall+0x233/0x820 init/main.c:1269 do_initcall_level+0x104/0x190 init/main.c:1331 do_initcalls+0x59/0xa0 init/main.c:1347 kernel_init_freeable+0x334/0x4b0 init/main.c:1579 kernel_init+0x1d/0x1d0 init/main.c:1469 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff8880574afd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880574afe00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880574afe80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880574aff00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ffff8880574aff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================