================================================================== BUG: KASAN: slab-use-after-free in rose_send_frame+0x29a/0x2c0 net/rose/rose_link.c:101 Read of size 8 at addr ffff888058a7cc20 by task kworker/u8:10/2117 CPU: 0 UID: 0 PID: 2117 Comm: kworker/u8:10 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: iou_exit io_ring_exit_work 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 rose_send_frame+0x29a/0x2c0 net/rose/rose_link.c:101 rose_transmit_restart_request+0x1b8/0x240 net/rose/rose_link.c:198 rose_t0timer_expiry+0x1d/0x150 net/rose/rose_link.c:83 call_timer_fn+0x19a/0x5a0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers+0x74a/0xae0 kernel/time/timer.c:2373 __run_timer_base kernel/time/timer.c:2385 [inline] __run_timer_base kernel/time/timer.c:2377 [inline] run_timer_base+0x114/0x190 kernel/time/timer.c:2394 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2404 handle_softirqs+0x219/0x950 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872 Code: b4 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 72 b8 ee 0e 0f 82 74 02 00 00 8b 35 0a e9 ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 89 b4 18 12 0f 85 ad 02 00 00 48 83 c4 RSP: 0018:ffffc90005567868 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e3c9620 RCX: 00000000c6ee6a25 RDX: 0000000000000000 RSI: ffffffff8daa7d80 RDI: ffffffff8bf2b380 RBP: 0000000000000002 R08: 000000000fca4a6a R09: 00000000a0fca4a6 R10: 0000000000000002 R11: ffff88802b1454b0 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] percpu_ref_put_many include/linux/percpu-refcount.h:330 [inline] percpu_ref_put include/linux/percpu-refcount.h:351 [inline] obj_cgroup_put include/linux/memcontrol.h:793 [inline] obj_cgroup_put include/linux/memcontrol.h:790 [inline] __memcg_slab_free_hook+0x2e5/0x590 mm/memcontrol.c:3241 memcg_slab_free_hook mm/slub.c:2364 [inline] slab_free mm/slub.c:6665 [inline] kmem_cache_free+0x52d/0x770 mm/slub.c:6779 __io_req_caches_free+0x19e/0x5c0 io_uring/io_uring.c:2826 io_req_caches_free io_uring/io_uring.c:2838 [inline] io_ring_exit_work+0x33c/0x1130 io_uring/io_uring.c:3024 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 23255: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:414 kmalloc_noprof include/linux/slab.h:957 [inline] rose_add_node net/rose/rose_route.c:85 [inline] rose_rt_ioctl+0x880/0x2580 net/rose/rose_route.c:748 rose_ioctl+0x64d/0x7c0 net/rose/af_rose.c:1382 sock_do_ioctl+0x118/0x280 net/socket.c:1254 sock_ioctl+0x227/0x6b0 net/socket.c:1375 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 25253: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6668 [inline] kfree+0x2f8/0x6e0 mm/slub.c:6876 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x53f/0x630 net/rose/rose_timer.c:183 call_timer_fn+0x19a/0x5a0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers+0x74a/0xae0 kernel/time/timer.c:2373 __run_timer_base kernel/time/timer.c:2385 [inline] __run_timer_base kernel/time/timer.c:2377 [inline] run_timer_base+0x114/0x190 kernel/time/timer.c:2394 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2404 handle_softirqs+0x219/0x950 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 The buggy address belongs to the object at ffff888058a7cc00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 32 bytes inside of freed 512-byte region [ffff888058a7cc00, ffff888058a7ce00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x58a7c 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 ffff88813ff26c80 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813ff26c80 0000000000000000 dead000000000001 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001629f01 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5811, tgid 5811 (syz-executor), ts 63973469432, free_ts 14167553901 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x2c3/0x430 mm/slub.c:3302 ___slab_alloc+0xe18/0x1c90 mm/slub.c:4656 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __do_kmalloc_node mm/slub.c:5656 [inline] __kmalloc_noprof+0x4fc/0x910 mm/slub.c:5669 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] __alloc_workqueue+0xe55/0x1810 kernel/workqueue.c:5717 alloc_workqueue_noprof+0xd2/0x200 kernel/workqueue.c:5820 wg_newlink+0x29e/0x7a0 drivers/net/wireguard/device.c:346 rtnl_newlink_create net/core/rtnetlink.c:3840 [inline] __rtnl_newlink net/core/rtnetlink.c:3957 [inline] rtnl_newlink+0xc19/0x1f50 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1894 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+0x7df/0x1170 mm/page_alloc.c:2943 __free_pages mm/page_alloc.c:5329 [inline] free_contig_range+0x183/0x4a0 mm/page_alloc.c:7197 destroy_args+0xb95/0x14e0 mm/debug_vm_pgtable.c:983 debug_vm_pgtable+0x2220/0x38d0 mm/debug_vm_pgtable.c:1372 do_one_initcall+0x123/0x680 init/main.c:1378 do_initcall_level init/main.c:1440 [inline] do_initcalls init/main.c:1456 [inline] do_basic_setup init/main.c:1475 [inline] kernel_init_freeable+0x5c8/0x920 init/main.c:1688 kernel_init+0x1c/0x2b0 init/main.c:1578 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Memory state around the buggy address: ffff888058a7cb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888058a7cb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888058a7cc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888058a7cc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888058a7cd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: b4 18 mov $0x18,%ah 2: 12 83 f8 07 0f 87 adc -0x78f0f808(%rbx),%al 8: a2 02 00 00 89 c0 48 movabs %al,0xa30f48c089000002 f: 0f a3 11: 05 72 b8 ee 0e add $0xeeeb872,%eax 16: 0f 82 74 02 00 00 jb 0x290 1c: 8b 35 0a e9 ee 0e mov 0xeeee90a(%rip),%esi # 0xeeee92c 22: 85 f6 test %esi,%esi 24: 0f 85 8d 00 00 00 jne 0xb7 * 2a: 48 8b 44 24 30 mov 0x30(%rsp),%rax <-- trapping instruction 2f: 65 48 2b 05 89 b4 18 sub %gs:0x1218b489(%rip),%rax # 0x1218b4c0 36: 12 37: 0f 85 ad 02 00 00 jne 0x2ea 3d: 48 rex.W 3e: 83 .byte 0x83 3f: c4 .byte 0xc4