================================================================== 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:513 [inline] BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x47c/0x800 net/xfrm/xfrm_state.c:753 Write of size 8 at addr ffff88805ea58430 by task syz.2.888/8726 CPU: 1 PID: 8726 Comm: syz.2.888 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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:982 [inline] hlist_del_rcu include/linux/rculist.h:513 [inline] __xfrm_state_delete+0x47c/0x800 net/xfrm/xfrm_state.c:753 xfrm_timer_handler+0x1c3/0x9e0 net/xfrm/xfrm_state.c:644 __run_hrtimer kernel/time/hrtimer.c:1755 [inline] __hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0033:0x7f3914a4d9d0 Code: 41 5e c3 0f 1f 80 00 00 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <41> 89 fb 44 8d 56 04 4c 8d 0d 22 46 35 00 89 f0 4c 8d 05 19 26 35 RSP: 002b:00007ffeacd7ea48 EFLAGS: 00000246 RAX: 000000000001a1ef RBX: 00007f39158e5720 RCX: 000000000000504c RDX: ffffffff81e372df RSI: ffffffff81e373db RDI: 0000000000000000 RBP: ffffffff81e373db R08: 00007f3914db6038 R09: 00007f3914da2000 R10: 00007f39145ff008 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff81e372df R15: 000000000000504c Allocated by task 6514: 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 The buggy address belongs to the object at ffff88805ea58400 which belongs to the cache xfrm_state of size 848 The buggy address is located 48 bytes inside of freed 848-byte region [ffff88805ea58400, ffff88805ea58750) The buggy address belongs to the physical page: page:ffffea00017a9600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805ea58800 pfn:0x5ea58 head:ffffea00017a9600 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 ffff88814565a500 dead000000000122 0000000000000000 raw: ffff88805ea58800 000000008010000d 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 6438, tgid 6437 (syz.1.226), ts 93617920484, free_ts 93542282256 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 xfrm_state_construct net/xfrm/xfrm_user.c:689 [inline] xfrm_add_sa+0xfe5/0x30a0 net/xfrm/xfrm_user.c:799 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 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 free_large_kmalloc+0x101/0x1a0 mm/slab_common.c:984 bpf_check+0x62c6/0xe970 kernel/bpf/verifier.c:20555 bpf_prog_load+0x11cb/0x16d0 kernel/bpf/syscall.c:2744 __sys_bpf+0x55a/0x800 kernel/bpf/syscall.c:5467 __do_sys_bpf kernel/bpf/syscall.c:5571 [inline] __se_sys_bpf kernel/bpf/syscall.c:5569 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5569 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: ffff88805ea58300: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc ffff88805ea58380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805ea58400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805ea58480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805ea58500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================