================================================================== BUG: KASAN: use-after-free in rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183 Read of size 2 at addr ffff8880613ef82a by task dhcpcd/3853 CPU: 0 PID: 3853 Comm: dhcpcd 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:finish_lock_switch+0x134/0x280 kernel/sched/core.c:4804 Code: be ff ff ff ff e8 4c 80 67 08 85 c0 74 4a 4d 85 ff 75 66 e9 fe 00 00 00 48 89 df e8 b6 eb 70 08 e8 41 e0 2a 00 fb 48 83 c4 08 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 c9 09 fe ff 43 80 3c RSP: 0018:ffffc900031bf568 EFLAGS: 00000282 RAX: 3fad0484fe59cb00 RBX: ffff8880b903a340 RCX: 3fad0484fe59cb00 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f780 RBP: 1ffff11017207613 R08: ffff8880b903a343 R09: 1ffff11017207468 R10: dffffc0000000000 R11: ffffed1017207469 R12: ffff8880b903b088 R13: dffffc0000000000 R14: ffff8880b903ae08 R15: 0000000000000000 finish_task_switch+0x12f/0x640 kernel/sched/core.c:4921 context_switch kernel/sched/core.c:5052 [inline] __schedule+0x11f7/0x43c0 kernel/sched/core.c:6395 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799 irqentry_exit+0x63/0x70 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681 RIP: 0010:security_sock_rcv_skb+0x0/0x90 security/security.c:2287 Code: c0 75 10 e8 62 a9 d7 fd eb b4 e8 5b a9 d7 fd 31 c0 eb 09 89 c3 e8 50 a9 d7 fd 89 d8 5b 41 5c 41 5d 41 5e 41 5f c3 0f 1f 40 00 <41> 57 41 56 41 55 41 54 53 48 89 f3 49 89 fe 49 bd 00 00 00 00 00 RSP: 0018:ffffc900031bf948 EFLAGS: 00000293 RAX: ffffffff87ea982f RBX: ffff888067503500 RCX: ffff888029883b80 RDX: 0000000000000000 RSI: ffff888067503500 RDI: ffff88802cfba000 RBP: ffffc900031bf9f0 R08: 6572646461204c4c R09: 1ffff1100aa6a707 R10: dffffc0000000000 R11: ffffed100aa6a708 R12: 0000000000000001 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88802cfba000 sk_filter_trim_cap+0x120/0x810 net/core/filter.c:142 sk_filter include/linux/filter.h:935 [inline] unix_dgram_sendmsg+0xafc/0x18a0 net/unix/af_unix.c:1840 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] sock_write_iter+0x2a6/0x3a0 net/socket.c:1089 call_write_iter include/linux/fs.h:2173 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x745/0xd60 fs/read_write.c:594 ksys_write+0x152/0x260 fs/read_write.c:647 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: 0033:0x7f156f492407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffca8ba6de0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f156f408740 RCX: 00007f156f492407 RDX: 000000000000003b RSI: 00007ffca8ba6e40 RDI: 0000000000000005 RBP: 000055b1613d4168 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffca8ba7270 R13: 000055b1744d7e90 R14: 000055b17415ed20 R15: 000055b17415df30 Allocated by task 26458: 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] rose_add_node+0x227/0xdb0 net/rose/rose_route.c:85 rose_rt_ioctl+0xa2b/0xe70 net/rose/rose_route.c:738 rose_ioctl+0x2a7/0x7d0 net/rose/af_rose.c:1372 sock_do_ioctl+0xfb/0x320 net/socket.c:1147 sock_ioctl+0x4d2/0x710 net/socket.c:1266 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860 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 Freed by task 28825: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kfree+0xef/0x2a0 mm/slub.c:4564 rose_rt_device_down+0x4e2/0x530 net/rose/rose_route.c:515 rose_device_event+0x606/0x6c0 net/rose/af_rose.c:247 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] __dev_notify_flags+0x158/0x300 net/core/dev.c:8893 dev_change_flags+0xe3/0x1a0 net/core/dev.c:8929 dev_ifsioc+0x130/0xd50 net/core/dev_ioctl.c:324 dev_ioctl+0x545/0xe30 net/core/dev_ioctl.c:572 sock_do_ioctl+0x245/0x320 net/socket.c:1161 sock_ioctl+0x4d2/0x710 net/socket.c:1266 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860 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 insert_work+0x54/0x3d0 kernel/workqueue.c:1366 __queue_work+0x9c5/0xd50 kernel/workqueue.c:1532 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1491 [inline] __run_timers+0x565/0x7f0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x339/0x830 kernel/softirq.c:576 run_ksoftirqd+0xa4/0x100 kernel/softirq.c:943 smpboot_thread_fn+0x4f6/0x970 kernel/smpboot.c:164 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Second to 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 insert_work+0x54/0x3d0 kernel/workqueue.c:1366 __queue_work+0x9c5/0xd50 kernel/workqueue.c:1532 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1491 [inline] __run_timers+0x565/0x7f0 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+0x142/0x210 kernel/softirq.c:477 __local_bh_enable_ip+0x180/0x1c0 kernel/softirq.c:401 spin_unlock_bh include/linux/spinlock.h:409 [inline] br_port_carrier_check+0x56b/0x700 net/bridge/br_if.c:89 br_device_event+0x4cd/0x880 net/bridge/br.c:89 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 netdev_state_change+0xe0/0x160 net/core/dev.c:1440 linkwatch_do_dev+0x10d/0x160 net/core/link_watch.c:167 __linkwatch_run_queue+0x4b1/0x7c0 net/core/link_watch.c:213 linkwatch_event+0x48/0x50 net/core/link_watch.c:252 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 process_scheduled_works kernel/workqueue.c:2373 [inline] worker_thread+0xd60/0x1290 kernel/workqueue.c:2459 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 ffff8880613ef800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of 512-byte region [ffff8880613ef800, ffff8880613efa00) The buggy address belongs to the page: page:ffffea000184fb00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880613ee000 pfn:0x613ec head:ffffea000184fb00 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea000184f708 ffffea00017fc308 ffff888016c41c80 raw: ffff8880613ee000 000000000010000e 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 4194, ts 58647747146, free_ts 19504284748 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] nlmsg_new include/net/netlink.h:953 [inline] inet_netconf_notify_devconf+0x16f/0x230 net/ipv4/devinet.c:2121 __devinet_sysctl_register+0x32a/0x3a0 net/ipv4/devinet.c:2609 devinet_sysctl_register+0x17c/0x1f0 net/ipv4/devinet.c:2643 inetdev_init+0x28c/0x4d0 net/ipv4/devinet.c:277 inetdev_event+0x26f/0x1370 net/ipv4/devinet.c:1543 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] register_netdevice+0x129d/0x16f0 net/core/dev.c:10428 veth_newlink+0x8d7/0xe30 drivers/net/veth.c:1714 __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: ffff8880613ef700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880613ef780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880613ef800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880613ef880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880613ef900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: be ff ff ff ff mov $0xffffffff,%esi 5: e8 4c 80 67 08 call 0x8678056 a: 85 c0 test %eax,%eax c: 74 4a je 0x58 e: 4d 85 ff test %r15,%r15 11: 75 66 jne 0x79 13: e9 fe 00 00 00 jmp 0x116 18: 48 89 df mov %rbx,%rdi 1b: e8 b6 eb 70 08 call 0x870ebd6 20: e8 41 e0 2a 00 call 0x2ae066 25: fb sti 26: 48 83 c4 08 add $0x8,%rsp * 2a: 5b pop %rbx <-- trapping instruction 2b: 41 5c pop %r12 2d: 41 5d pop %r13 2f: 41 5e pop %r14 31: 41 5f pop %r15 33: 5d pop %rbp 34: c3 ret 35: 48 89 df mov %rbx,%rdi 38: e8 c9 09 fe ff call 0xfffe0a06 3d: 43 rex.XB 3e: 80 .byte 0x80 3f: 3c .byte 0x3c