================================================================== BUG: KASAN: use-after-free in rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183 Read of size 2 at addr ffff88806159bc2a by task rm/10985 CPU: 0 PID: 10985 Comm: rm Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x53a/0x7f0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x339/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:zap_pte_range mm/memory.c:1375 [inline] RIP: 0010:zap_pmd_range mm/memory.c:1505 [inline] RIP: 0010:zap_pud_range mm/memory.c:1534 [inline] RIP: 0010:zap_p4d_range mm/memory.c:1555 [inline] RIP: 0010:unmap_page_range+0xd40/0x2500 mm/memory.c:1576 Code: de 48 83 e6 01 31 ff e8 5e 9f cb ff 48 83 e3 01 75 1f 48 8b 5c 24 78 89 de 83 e6 40 31 ff e8 c7 9e cb ff 89 d8 83 e0 40 75 11 5b 9b cb ff eb 22 e8 54 9b cb ff e9 98 00 00 00 e8 4a 9b cb ff RSP: 0018:ffffc90004a0f8a0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 000000000a03c025 RCX: ffff88801ed91dc0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90004a0fa10 R08: ffff88801ed91dc7 R09: 1ffff11003db23b8 R10: dffffc0000000000 R11: ffffed1003db23b9 R12: ffffea0000280f18 R13: 00007fa4c638b000 R14: ffffea0000280f08 R15: ffffea0000280f00 unmap_vmas+0x131/0x250 mm/memory.c:1653 exit_mmap+0x3b9/0x640 mm/mmap.c:3216 __mmput+0x115/0x3b0 kernel/fork.c:1127 exit_mm+0x588/0x6e0 kernel/exit.c:550 do_exit+0x5a9/0x20c0 kernel/exit.c:870 do_group_exit+0x12e/0x300 kernel/exit.c:997 __do_sys_exit_group kernel/exit.c:1008 [inline] __se_sys_exit_group kernel/exit.c:1006 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fa4c634b6c5 Code: Unable to access opcode bytes at RIP 0x7fa4c634b69b. RSP: 002b:00007fffbe10ffe8 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007fa4c644cfe8 RCX: 00007fa4c634b6c5 RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000 RBP: 0000000000000001 R08: 00007fffbe10ff78 R09: 0000000000000000 R10: 00007fffbe10fe10 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa4c644b680 R15: 00007fa4c644d000 Allocated by task 4178: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] kernfs_fop_open+0x3da/0xbf0 fs/kernfs/file.c:628 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x26f5/0x2fa0 fs/namei.c:3750 do_filp_open+0x1e2/0x410 fs/namei.c:3777 do_sys_openat2+0x150/0x4b0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_openat fs/open.c:1287 [inline] __se_sys_openat fs/open.c:1282 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1282 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 kvfree_call_rcu+0x105/0x7d0 kernel/rcu/tree.c:3600 drop_sysctl_table+0x359/0x4e0 fs/proc/proc_sysctl.c:1685 drop_sysctl_table+0x348/0x4e0 fs/proc/proc_sysctl.c:1688 unregister_sysctl_table+0x87/0x130 fs/proc/proc_sysctl.c:1723 neigh_sysctl_unregister+0x74/0x90 net/core/neighbour.c:3737 addrconf_sysctl_unregister net/ipv6/addrconf.c:7162 [inline] addrconf_ifdown+0x16cb/0x19c0 net/ipv6/addrconf.c:3928 addrconf_notify+0x445/0xf00 net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] unregister_netdevice_many+0x1049/0x19f0 net/core/dev.c:11134 unregister_netdevice_queue+0x324/0x370 net/core/dev.c:11067 unregister_netdevice include/linux/netdevice.h:3029 [inline] __tun_detach+0xd4a/0x1500 drivers/net/tun.c:686 tun_detach drivers/net/tun.c:702 [inline] tun_chr_close+0x109/0x1b0 drivers/net/tun.c:3440 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88806159bc00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of 512-byte region [ffff88806159bc00, ffff88806159be00) The buggy address belongs to the page: page:ffffea0001856600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888061599000 pfn:0x61598 head:ffffea0001856600 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00017f0e08 ffffea0001830708 ffff888016c41c80 raw: ffff888061599000 0000000000100004 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4184, ts 70144748868, free_ts 21791406105 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5487 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x80a/0xdd0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] __kmalloc_node_track_caller+0x1fc/0x3a0 mm/slub.c:4963 kmalloc_reserve net/core/skbuff.c:356 [inline] __alloc_skb+0x22c/0x750 net/core/skbuff.c:427 alloc_skb include/linux/skbuff.h:1162 [inline] alloc_uevent_skb+0x7d/0x230 lib/kobject_uevent.c:290 uevent_net_broadcast_tagged lib/kobject_uevent.c:351 [inline] kobject_uevent_net_broadcast+0x17e/0x530 lib/kobject_uevent.c:412 kobject_uevent_env+0x556/0x890 lib/kobject_uevent.c:608 device_add+0x91c/0xfb0 drivers/base/core.c:3393 netdev_register_kobject+0x184/0x320 net/core/net-sysfs.c:2014 register_netdevice+0x1039/0x16f0 net/core/dev.c:10397 hsr_dev_finalize+0x5f6/0x870 net/hsr/hsr_device.c:689 hsr_newlink+0x637/0x6f0 net/hsr/hsr_netlink.c:102 __rtnl_newlink net/core/rtnetlink.c:3526 [inline] rtnl_newlink+0x1359/0x1a50 net/core/rtnetlink.c:3574 rtnetlink_rcv_msg+0x844/0xf30 net/core/rtnetlink.c:5684 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396 free_contig_range+0x96/0xf0 mm/page_alloc.c:9406 destroy_args+0xf0/0xa00 mm/debug_vm_pgtable.c:1018 debug_vm_pgtable+0x321/0x380 mm/debug_vm_pgtable.c:1336 do_one_initcall+0x272/0x730 init/main.c:1316 do_initcall_level+0x137/0x1f0 init/main.c:1389 do_initcalls+0x4b/0x90 init/main.c:1405 kernel_init_freeable+0x3e9/0x570 init/main.c:1629 kernel_init+0x19/0x1b0 init/main.c:1520 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Memory state around the buggy address: ffff88806159bb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806159bb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88806159bc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806159bc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806159bd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: de 48 83 fimuls -0x7d(%rax) 3: e6 01 out %al,$0x1 5: 31 ff xor %edi,%edi 7: e8 5e 9f cb ff call 0xffcb9f6a c: 48 83 e3 01 and $0x1,%rbx 10: 75 1f jne 0x31 12: 48 8b 5c 24 78 mov 0x78(%rsp),%rbx 17: 89 de mov %ebx,%esi 19: 83 e6 40 and $0x40,%esi 1c: 31 ff xor %edi,%edi 1e: e8 c7 9e cb ff call 0xffcb9eea 23: 89 d8 mov %ebx,%eax 25: 83 e0 40 and $0x40,%eax 28: 75 11 jne 0x3b * 2a: e8 5b 9b cb ff call 0xffcb9b8a <-- trapping instruction 2f: eb 22 jmp 0x53 31: e8 54 9b cb ff call 0xffcb9b8a 36: e9 98 00 00 00 jmp 0xd3 3b: e8 4a 9b cb ff call 0xffcb9b8a