================================================================== BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:982 [inline] BUG: KASAN: slab-use-after-free in hlist_del_rcu include/linux/rculist.h:560 [inline] BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x696/0xca0 net/xfrm/xfrm_state.c:830 Write of size 8 at addr ffff8880591348b0 by task syz.6.776/9459 CPU: 1 UID: 0 PID: 9459 Comm: syz.6.776 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 __hlist_del include/linux/list.h:982 [inline] hlist_del_rcu include/linux/rculist.h:560 [inline] __xfrm_state_delete+0x696/0xca0 net/xfrm/xfrm_state.c:830 xfrm_timer_handler+0x18f/0xa00 net/xfrm/xfrm_state.c:716 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1842 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5893 Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 db d0 02 11 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000aee7018 EFLAGS: 00000206 RAX: 899ed0255fbba200 RBX: 0000000000000202 RCX: 899ed0255fbba200 RDX: 0000000000000004 RSI: ffffffff8dba5d03 RDI: ffffffff8be33300 RBP: ffff88802f4fc790 R08: ffffc9000aee710f R09: 0000000000000000 R10: ffffc9000aee7100 R11: ffffffffa02019cc R12: 0000000000000004 R13: 0000000000000004 R14: ffffffff8e139ea0 R15: ffff88802f4fbc00 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] trace_call_bpf+0x5a9/0x850 kernel/trace/bpf_trace.c:148 perf_trace_run_bpf_submit+0x78/0x170 kernel/events/core.c:10911 do_perf_trace_lock include/trace/events/lock.h:50 [inline] perf_trace_lock+0x2f8/0x3b0 include/trace/events/lock.h:50 __do_trace_lock_release include/trace/events/lock.h:69 [inline] trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x3b2/0x3e0 kernel/locking/lockdep.c:5879 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] page_table_check_clear+0x4f3/0x700 mm/page_table_check.c:89 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline] get_and_clear_full_ptes include/linux/pgtable.h:725 [inline] zap_present_folio_ptes mm/memory.c:1499 [inline] zap_present_ptes mm/memory.c:1581 [inline] do_zap_pte_range mm/memory.c:1682 [inline] zap_pte_range mm/memory.c:1726 [inline] zap_pmd_range mm/memory.c:1818 [inline] zap_pud_range mm/memory.c:1847 [inline] zap_p4d_range mm/memory.c:1868 [inline] unmap_page_range+0x3445/0x4370 mm/memory.c:1889 unmap_single_vma mm/memory.c:1932 [inline] unmap_vmas+0x399/0x580 mm/memory.c:1976 exit_mmap+0x248/0xb50 mm/mmap.c:1280 __mmput+0x118/0x420 kernel/fork.c:1130 exit_mm+0x1da/0x2c0 kernel/exit.c:582 do_exit+0x648/0x2300 kernel/exit.c:949 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff1d638eba9 Code: Unable to access opcode bytes at 0x7ff1d638eb7f. RSP: 002b:00007ff1d72b5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: fffffffffffffff5 RBX: 00007ff1d65d5fa0 RCX: 00007ff1d638eba9 RDX: 0000000000000094 RSI: 0000200000000880 RDI: 0000000000000005 RBP: 00007ff1d6411e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff1d65d6038 R14: 00007ff1d65d5fa0 R15: 00007fff9f586008 Allocated by task 8519: 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 10: 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+0x711/0x8a0 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 ffff888059134880 which belongs to the cache xfrm_state of size 928 The buggy address is located 48 bytes inside of freed 928-byte region [ffff888059134880, ffff888059134c20) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888059134000 pfn:0x59134 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff888142ab7500 dead000000000122 0000000000000000 raw: ffff888059134000 00000000800f000e 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff888142ab7500 dead000000000122 0000000000000000 head: ffff888059134000 00000000800f000e 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001644d01 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 6756, tgid 6755 (syz.2.205), ts 141922746280, free_ts 141613259401 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 __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 page last free pid 6746 tgid 6744 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 stack_depot_save_flags+0x436/0x860 lib/stackdepot.c:727 kasan_save_stack mm/kasan/common.c:48 [inline] kasan_save_track+0x4f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4365 [inline] __kmalloc_node_noprof+0x276/0x4e0 mm/slub.c:4371 kmalloc_array_node_noprof include/linux/slab.h:1020 [inline] alloc_slab_obj_exts mm/slub.c:2028 [inline] account_slab mm/slub.c:2614 [inline] allocate_slab+0x16a/0x370 mm/slub.c:2674 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 sk_prot_alloc+0x57/0x220 net/core/sock.c:2233 sk_alloc+0x3a/0x370 net/core/sock.c:2295 inet_create+0x7a0/0x1000 net/ipv4/af_inet.c:326 __sock_create+0x4b3/0x9f0 net/socket.c:1589 smc_create_clcsk net/smc/af_smc.c:3347 [inline] __smc_create+0x199/0x280 net/smc/af_smc.c:3392 __sock_create+0x4b3/0x9f0 net/socket.c:1589 sock_create net/socket.c:1647 [inline] __sys_socket_create net/socket.c:1684 [inline] __sys_socket+0xd7/0x1b0 net/socket.c:1731 __do_sys_socket net/socket.c:1745 [inline] __se_sys_socket net/socket.c:1743 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1743 Memory state around the buggy address: ffff888059134780: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888059134800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888059134880: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888059134900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888059134980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 51 push %rcx 1: 48 c7 44 24 20 00 00 movq $0x0,0x20(%rsp) 8: 00 00 a: 9c pushf b: 8f 44 24 20 pop 0x20(%rsp) f: f7 44 24 20 00 02 00 testl $0x200,0x20(%rsp) 16: 00 17: 75 56 jne 0x6f 19: f7 c3 00 02 00 00 test $0x200,%ebx 1f: 74 01 je 0x22 21: fb sti 22: 65 48 8b 05 db d0 02 mov %gs:0x1102d0db(%rip),%rax # 0x1102d105 29: 11 * 2a: 48 3b 44 24 28 cmp 0x28(%rsp),%rax <-- trapping instruction 2f: 0f 85 8b 00 00 00 jne 0xc0 35: 48 83 c4 30 add $0x30,%rsp 39: 5b pop %rbx 3a: 41 5c pop %r12 3c: 41 5d pop %r13 3e: 41 5e pop %r14