================================================================== BUG: KASAN: slab-use-after-free in __xfrm_state_insert+0x24fc/0x2510 net/xfrm/xfrm_state.c:1743 Read of size 1 at addr ffff888079693a70 by task syz.3.1659/12842 CPU: 1 UID: 0 PID: 12842 Comm: syz.3.1659 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 __xfrm_state_insert+0x24fc/0x2510 net/xfrm/xfrm_state.c:1743 xfrm_state_insert+0x4c/0x60 net/xfrm/xfrm_state.c:1795 ipcomp6_tunnel_attach net/ipv6/ipcomp6.c:131 [inline] ipcomp6_init_state net/ipv6/ipcomp6.c:163 [inline] ipcomp6_init_state+0x608/0x8d0 net/ipv6/ipcomp6.c:141 __xfrm_init_state+0x6fe/0x1c10 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+0x24f4/0x2ec0 net/key/af_key.c:1504 pfkey_process+0x6d9/0x840 net/key/af_key.c:2848 pfkey_sendmsg+0x435/0x850 net/key/af_key.c:3699 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa98/0xc70 net/socket.c:2614 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668 __sys_sendmsg+0x16d/0x220 net/socket.c:2700 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe9ec98ebe9 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:00007fe9ed73a038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fe9ecbb6180 RCX: 00007fe9ec98ebe9 RDX: 0000000000000000 RSI: 00002000000001c0 RDI: 0000000000000007 RBP: 00007fe9eca11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe9ecbb6218 R14: 00007fe9ecbb6180 R15: 00007ffdf4256ca8 Allocated by task 12087: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x89/0x90 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+0x1cb/0x3b0 mm/slub.c:4236 xfrm_state_alloc+0x23/0x5c0 net/xfrm/xfrm_state.c:733 __find_acq_core+0xb59/0x2900 net/xfrm/xfrm_state.c:1833 xfrm_find_acq+0x7b/0xa0 net/xfrm/xfrm_state.c:2353 xfrm_alloc_userspi+0x58e/0xbb0 net/xfrm/xfrm_user.c:1863 xfrm_user_rcv_msg+0x58e/0xc00 net/xfrm/xfrm_user.c:3501 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552 xfrm_netlink_rcv+0x71/0x90 net/xfrm/xfrm_user.c:3523 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa98/0xc70 net/socket.c:2614 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668 __sys_sendmsg+0x16d/0x220 net/socket.c:2700 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 9: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x60/0x70 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+0x2d1/0x4d0 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+0x50a/0x770 net/xfrm/xfrm_state.c:634 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 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 ffff888079693740 which belongs to the cache xfrm_state of size 928 The buggy address is located 816 bytes inside of freed 928-byte region [ffff888079693740, ffff888079693ae0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888079692a80 pfn:0x79690 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff8880212f4280 ffffea0001548300 0000000000000003 raw: ffff888079692a80 00000000800f000c 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff8880212f4280 ffffea0001548300 0000000000000003 head: ffff888079692a80 00000000800f000c 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001e5a401 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 6274, tgid 6268 (syz.2.47), ts 89196868269, free_ts 88416079488 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab mm/slub.c:2655 [inline] new_slab+0x247/0x330 mm/slub.c:2709 ___slab_alloc+0xcf2/0x1740 mm/slub.c:3891 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981 __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_noprof+0xef/0x3b0 mm/slub.c:4236 xfrm_state_alloc+0x23/0x5c0 net/xfrm/xfrm_state.c:733 xfrm_state_find+0x31e6/0x84c0 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+0x4cd/0x3740 net/xfrm/xfrm_policy.c:2871 xfrm_lookup_with_ifid+0x2a0/0x1e40 net/xfrm/xfrm_policy.c:3205 xfrm_lookup net/xfrm/xfrm_policy.c:3336 [inline] xfrm_lookup_route+0x3b/0x200 net/xfrm/xfrm_policy.c:3347 ip6_dst_lookup_flow+0x15c/0x1d0 net/ipv6/ip6_output.c:1268 rawv6_sendmsg+0xe85/0x4820 net/ipv6/raw.c:893 inet_sendmsg+0x11c/0x140 net/ipv4/af_inet.c:851 page last free pid 3002 tgid 3002 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895 ops_free_list net/core/net_namespace.c:214 [inline] ops_undo_list+0x487/0xab0 net/core/net_namespace.c:255 cleanup_net+0x408/0x890 net/core/net_namespace.c:682 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 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: ffff888079693900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888079693980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888079693a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888079693a80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888079693b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================