================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff88805f9e482a by task syz-executor/17721 CPU: 1 PID: 17721 Comm: syz-executor Not tainted 6.6.102-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 rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x52d/0x7d0 kernel/time/timer.c:2022 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035 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+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:preempt_latency_start kernel/sched/core.c:5828 [inline] RIP: 0010:preempt_count_add+0xa6/0x1a0 kernel/sched/core.c:5851 Code: ff ff ff 7f 39 f8 75 42 48 8b 5c 24 18 48 89 df e8 ef d2 0c 00 85 c0 74 09 31 db 31 ff e8 e2 d2 0c 00 65 4c 8b 35 1a 50 a8 7e <49> 81 c6 c8 14 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c RSP: 0018:ffffc90003597830 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff813aa37e RCX: ffffffff96eaa400 RDX: ffff888079d19e00 RSI: 0000000000000001 RDI: ffffffff813aa37e RBP: 0000000000000001 R08: ffffc90003597901 R09: 0000000000000000 R10: ffffc90003597988 R11: fffff520006b2f3d R12: ffffc90003597988 R13: dffffc0000000000 R14: ffff888079d19e00 R15: dffffc0000000000 unwind_next_frame+0xbe/0x2970 arch/x86/kernel/unwind_orc.c:479 __unwind_start+0x66a/0x7e0 arch/x86/kernel/unwind_orc.c:760 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xf8/0x190 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] kmem_cache_free+0xf8/0x280 mm/slub.c:3838 do_sys_openat2+0x168/0x1c0 fs/open.c:1427 do_sys_open fs/open.c:1434 [inline] __do_sys_openat fs/open.c:1450 [inline] __se_sys_openat fs/open.c:1445 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1445 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 RIP: 0033:0x7ff2c6d8d550 Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 49 94 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 9c 94 02 00 8b 44 RSP: 002b:00007fff90dc5f10 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000080001 RCX: 00007ff2c6d8d550 RDX: 0000000000080001 RSI: 00007ff2c6e136a0 RDI: 00000000ffffff9c RBP: 00007ff2c6e136a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000004 R13: 00007fff90dc5fb0 R14: 00000000000a776e R15: 00007fff90dc6520 Allocated by task 11957: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] rose_add_node+0x23a/0xdd0 net/rose/rose_route.c:85 rose_rt_ioctl+0xa42/0xfb0 net/rose/rose_route.c:740 rose_ioctl+0x3cf/0x8b0 net/rose/af_rose.c:1380 sock_do_ioctl+0xd7/0x2f0 net/socket.c:1222 sock_ioctl+0x623/0x7a0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 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 Freed by task 17544: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829 rose_rt_device_down+0x43d/0x490 net/rose/rose_route.c:515 rose_device_event+0x604/0x690 net/rose/af_rose.c:248 notifier_call_chain+0x197/0x390 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2064 [inline] call_netdevice_notifiers net/core/dev.c:2078 [inline] __dev_notify_flags+0x18e/0x2e0 net/core/dev.c:-1 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8750 dev_ifsioc+0x6a7/0xe20 net/core/dev_ioctl.c:529 dev_ioctl+0x7e2/0x1170 net/core/dev_ioctl.c:786 sock_do_ioctl+0x226/0x2f0 net/socket.c:1236 sock_ioctl+0x623/0x7a0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 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 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x158/0x930 kernel/rcu/tree.c:2837 fib6_info_release include/net/ip6_fib.h:339 [inline] ip6_route_info_create+0x9c0/0x1200 net/ipv6/route.c:3875 ip6_route_add+0x28/0x130 net/ipv6/route.c:3889 addrconf_prefix_route+0x211/0x2b0 net/ipv6/addrconf.c:2451 inet6_addr_add+0x64a/0xb60 net/ipv6/addrconf.c:3035 inet6_rtm_newaddr+0x68d/0x940 net/ipv6/addrconf.c:5004 rtnetlink_rcv_msg+0x7c7/0xf10 net/core/rtnetlink.c:6475 netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2555 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1356 netlink_sendmsg+0x8c1/0xbe0 net/netlink/af_netlink.c:1904 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x46a/0x620 net/socket.c:2201 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2209 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 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x158/0x930 kernel/rcu/tree.c:2837 fib6_info_release include/net/ip6_fib.h:339 [inline] __ip6_del_rt+0xf1/0x150 net/ipv6/route.c:3916 ip6_del_rt+0xb4/0x100 net/ipv6/route.c:3927 __ipv6_ifa_notify+0x5be/0xaa0 net/ipv6/addrconf.c:6274 addrconf_ifdown+0xe6a/0x1880 net/ipv6/addrconf.c:3950 addrconf_notify+0x6c6/0x1010 net/ipv6/addrconf.c:-1 notifier_call_chain+0x197/0x390 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2064 [inline] call_netdevice_notifiers net/core/dev.c:2078 [inline] dev_close_many+0x297/0x400 net/core/dev.c:1619 unregister_netdevice_many_notify+0x4c1/0x1810 net/core/dev.c:11047 unregister_netdevice_many net/core/dev.c:11130 [inline] default_device_exit_batch+0x9cb/0xa60 net/core/dev.c:11608 ops_exit_list net/core/net_namespace.c:178 [inline] cleanup_net+0x77f/0xb90 net/core/net_namespace.c:652 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88805f9e4800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff88805f9e4800, ffff88805f9e4a00) The buggy address belongs to the physical page: page:ffffea00017e7900 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805f9e4000 pfn:0x5f9e4 head:ffffea00017e7900 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 ffff888017841c80 ffffea0000963910 ffffea0000946b10 raw: ffff88805f9e4000 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 8738, tgid 8738 (syz-executor), ts 277641589447, free_ts 275227344601 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] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] fib6_info_alloc+0x32/0xe0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x44f/0x1200 net/ipv6/route.c:3793 addrconf_f6i_alloc+0x1c6/0x400 net/ipv6/route.c:4621 ipv6_add_addr+0x576/0x1090 net/ipv6/addrconf.c:1129 inet6_addr_add+0x57e/0xb60 net/ipv6/addrconf.c:3032 inet6_rtm_newaddr+0x68d/0x940 net/ipv6/addrconf.c:5004 rtnetlink_rcv_msg+0x7c7/0xf10 net/core/rtnetlink.c:6475 netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2555 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_pages_ok+0x9b3/0xad0 mm/page_alloc.c:1284 free_large_kmalloc+0x101/0x1a0 mm/slab_common.c:984 proc_sys_call_handler+0x50f/0x6d0 fs/proc/proc_sysctl.c:611 call_read_iter include/linux/fs.h:2012 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x431/0x920 fs/read_write.c:470 ksys_read+0x147/0x250 fs/read_write.c:613 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: ffff88805f9e4700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805f9e4780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805f9e4800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805f9e4880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805f9e4900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 3 bytes skipped: 0: 7f 39 jg 0x3b 2: f8 clc 3: 75 42 jne 0x47 5: 48 8b 5c 24 18 mov 0x18(%rsp),%rbx a: 48 89 df mov %rbx,%rdi d: e8 ef d2 0c 00 call 0xcd301 12: 85 c0 test %eax,%eax 14: 74 09 je 0x1f 16: 31 db xor %ebx,%ebx 18: 31 ff xor %edi,%edi 1a: e8 e2 d2 0c 00 call 0xcd301 1f: 65 4c 8b 35 1a 50 a8 mov %gs:0x7ea8501a(%rip),%r14 # 0x7ea85041 26: 7e * 27: 49 81 c6 c8 14 00 00 add $0x14c8,%r14 <-- trapping instruction 2e: 4c 89 f0 mov %r14,%rax 31: 48 c1 e8 03 shr $0x3,%rax 35: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) 3a: 74 08 je 0x44 3c: 4c rex.WR