================================================================== BUG: KASAN: use-after-free in rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183 Read of size 2 at addr ffff888025f3e82a by task syz.2.605/7099 CPU: 0 PID: 7099 Comm: syz.2.605 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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:1648 expire_timers kernel/time/timer.c:1699 [inline] __run_timers+0x53e/0x800 kernel/time/timer.c:1970 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194 Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 2f 8a 8c f7 65 8b 05 d0 97 3c 76 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc90002f0f420 EFLAGS: 00000206 RAX: dffffc0000000004 RBX: 0000000000000a02 RCX: 7af09d19442c9000 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: 0000000000000001 RBP: ffffc90002f0f4b0 R08: ffffffff901d4107 R09: 1ffffffff203a820 R10: dffffc0000000000 R11: fffffbfff203a821 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff888028915050 R15: 1ffff920005e1e84 spin_unlock_irqrestore include/linux/spinlock.h:419 [inline] unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1538 [inline] __pagevec_lru_add+0x13e9/0x1780 mm/swap.c:1055 lru_cache_add+0x516/0x750 mm/swap.c:453 shmem_getpage_gfp+0x186b/0x2d40 mm/shmem.c:1945 shmem_fault+0x1ac/0x540 mm/shmem.c:2118 __do_fault+0x141/0x330 mm/memory.c:3928 do_read_fault mm/memory.c:4264 [inline] do_fault mm/memory.c:4392 [inline] handle_pte_fault mm/memory.c:4650 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x2985/0x4410 mm/memory.c:4883 faultin_page mm/gup.c:976 [inline] __get_user_pages+0x94b/0x11e0 mm/gup.c:1197 populate_vma_page_range+0x213/0x290 mm/gup.c:1529 __mm_populate+0x275/0x3b0 mm/gup.c:1638 mm_populate include/linux/mm.h:2646 [inline] vm_mmap_pgoff+0x212/0x2d0 mm/util.c:556 ksys_mmap_pgoff+0x140/0x790 mm/mmap.c:1635 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: 0033:0x7feec3c84799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007feec1ede028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007feec3efdfa0 RCX: 00007feec3c84799 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007feec3d1ac99 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007feec3efe038 R14: 00007feec3efdfa0 R15: 00007ffcfa537ce8 Allocated by task 6023: 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:612 [inline] kzalloc include/linux/slab.h:738 [inline] fib6_info_alloc+0x2e/0xe0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x44f/0x1210 net/ipv6/route.c:3769 ip6_route_add+0x24/0x130 net/ipv6/route.c:3865 addrconf_prefix_route net/ipv6/addrconf.c:2446 [inline] fixup_permanent_addr net/ipv6/addrconf.c:3524 [inline] addrconf_permanent_addr+0x692/0xa00 net/ipv6/addrconf.c:3548 addrconf_notify+0x827/0xf00 net/ipv6/addrconf.c:3616 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:2074 [inline] call_netdevice_notifiers net/core/dev.c:2088 [inline] __dev_notify_flags+0x194/0x300 net/core/dev.c:8917 dev_change_flags+0xe3/0x1a0 net/core/dev.c:8955 do_setlink+0xcdb/0x3d60 net/core/rtnetlink.c:2781 __rtnl_newlink net/core/rtnetlink.c:3452 [inline] rtnl_newlink+0x1658/0x1a50 net/core/rtnetlink.c:3574 rtnetlink_rcv_msg+0x844/0xf30 net/core/rtnetlink.c:5684 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2507 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] __sys_sendto+0x46d/0x620 net/socket.c:2072 __do_sys_sendto net/socket.c:2084 [inline] __se_sys_sendto net/socket.c:2080 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2080 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 __call_rcu kernel/rcu/tree.c:3011 [inline] call_rcu+0x189/0x950 kernel/rcu/tree.c:3091 fib6_info_release include/net/ip6_fib.h:339 [inline] fib6_del_route net/ipv6/ip6_fib.c:1998 [inline] fib6_del+0x112b/0x1550 net/ipv6/ip6_fib.c:2031 fib6_clean_node+0x293/0x540 net/ipv6/ip6_fib.c:2193 fib6_walk_continue+0x640/0x8c0 net/ipv6/ip6_fib.c:2115 fib6_walk+0x149/0x290 net/ipv6/ip6_fib.c:2163 fib6_clean_tree net/ipv6/ip6_fib.c:2243 [inline] __fib6_clean_all+0x25f/0x3c0 net/ipv6/ip6_fib.c:2259 rt6_sync_down_dev net/ipv6/route.c:4915 [inline] rt6_disable_ip+0x127/0x6b0 net/ipv6/route.c:4920 addrconf_ifdown+0x155/0x19c0 net/ipv6/addrconf.c:3775 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:2074 [inline] call_netdevice_notifiers net/core/dev.c:2088 [inline] dev_close_many+0x29f/0x400 net/core/dev.c:1663 unregister_netdevice_many+0x481/0x19f0 net/core/dev.c:11136 default_device_exit_batch+0x364/0x3c0 net/core/dev.c:11693 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x791/0xba0 net/core/net_namespace.c:635 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 The buggy address belongs to the object at ffff888025f3e800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of 512-byte region [ffff888025f3e800, ffff888025f3ea00) The buggy address belongs to the page: page:ffffea000097cf00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888025f3d400 pfn:0x25f3c head:ffffea000097cf00 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00017f6908 ffffea000174b908 ffff888016c41c80 raw: ffff888025f3d400 0000000000100006 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 2422, ts 10985894609, free_ts 0 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:5501 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] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc_trace+0x1a5/0x2a0 mm/slub.c:3250 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] alloc_bprm+0x56/0x6a0 fs/exec.c:1516 kernel_execve+0x49/0x900 fs/exec.c:1978 call_usermodehelper_exec_async+0x207/0x350 kernel/umh.c:112 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 page_owner free stack trace missing Memory state around the buggy address: ffff888025f3e700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888025f3e780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888025f3e800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888025f3e880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888025f3e900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: c7 44 24 20 00 00 00 movl $0x0,0x20(%rsp) 7: 00 8: 9c pushf 9: 8f 44 24 20 pop 0x20(%rsp) d: f7 44 24 20 00 02 00 testl $0x200,0x20(%rsp) 14: 00 15: 41 c6 04 07 f8 movb $0xf8,(%r15,%rax,1) 1a: 75 4b jne 0x67 1c: f7 c3 00 02 00 00 test $0x200,%ebx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 2f 8a 8c f7 call 0xf78c8a5e <-- trapping instruction 2f: 65 8b 05 d0 97 3c 76 mov %gs:0x763c97d0(%rip),%eax # 0x763c9806 36: 85 c0 test %eax,%eax 38: 74 3c je 0x76 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss