netlink: 12 bytes leftover after parsing attributes in process `syz.8.1278'. ================================================================== BUG: KASAN: slab-out-of-bounds in ax25_dev_device_down+0x9c/0x67c net/ax25/ax25_dev.c:113 Read of size 8 at addr ffff0000db07d508 by task syz.8.1278/9822 CPU: 1 PID: 9822 Comm: syz.8.1278 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 Call trace: dump_backtrace+0x0/0x43c arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 print_address_description+0x78/0x30c mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xec/0x15c mm/kasan/report.c:451 __asan_report_load8_noabort+0x44/0x50 mm/kasan/report_generic.c:309 ax25_dev_device_down+0x9c/0x67c net/ax25/ax25_dev.c:113 ax25_device_event+0x538/0x590 net/ax25/af_ax25.c:144 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2049 [inline] call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] dev_close_many+0x2cc/0x440 net/core/dev.c:1650 dev_close+0x148/0x1f8 net/core/dev.c:1672 bpq_device_event+0x318/0x824 drivers/net/hamradio/bpqether.c:548 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2049 [inline] call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] dev_close_many+0x2cc/0x440 net/core/dev.c:1650 dev_close+0x148/0x1f8 net/core/dev.c:1672 bond_setup_by_slave+0x70/0x318 drivers/net/bonding/bond_main.c:1471 bond_enslave+0x624/0x3014 drivers/net/bonding/bond_main.c:1855 bond_do_ioctl+0x6ec/0xb3c drivers/net/bonding/bond_main.c:4238 bond_siocdevprivate+0x18c/0x1dc drivers/net/bonding/bond_main.c:-1 dev_siocdevprivate net/core/dev_ioctl.c:285 [inline] dev_ifsioc+0xa30/0xef4 net/core/dev_ioctl.c:403 dev_ioctl+0x550/0xc94 net/core/dev_ioctl.c:612 sock_ioctl+0x7e0/0x87c net/socket.c:1184 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Allocated by task 8174: 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+0xb0/0xf0 mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:264 [inline] __kmalloc+0x298/0x44c mm/slub.c:4407 kmalloc include/linux/slab.h:609 [inline] kzalloc include/linux/slab.h:735 [inline] new_dir fs/proc/proc_sysctl.c:959 [inline] get_subdir fs/proc/proc_sysctl.c:1004 [inline] __register_sysctl_table+0x8d4/0xfb0 fs/proc/proc_sysctl.c:1353 register_net_sysctl+0x2e4/0x330 net/sysctl_net.c:169 mpls_dev_sysctl_register+0x198/0x25c net/mpls/af_mpls.c:1421 mpls_add_dev net/mpls/af_mpls.c:1476 [inline] mpls_dev_notify+0x330/0x738 net/mpls/af_mpls.c:1621 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2049 [inline] call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers+0x10c/0x18c net/core/dev.c:2075 register_netdevice+0xf04/0x1304 net/core/dev.c:10428 cfg80211_register_netdevice+0x12c/0x298 net/wireless/core.c:1356 ieee80211_if_add+0xeec/0x1ce0 net/mac80211/iface.c:2078 ieee80211_register_hw+0x21dc/0x2f58 net/mac80211/main.c:1323 mac80211_hwsim_new_radio+0x19fc/0x371c drivers/net/wireless/mac80211_hwsim.c:3374 hwsim_new_radio_nl+0x838/0xba0 drivers/net/wireless/mac80211_hwsim.c:3950 genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline] genl_family_rcv_msg net/netlink/genetlink.c:775 [inline] genl_rcv_msg+0x8b4/0xb6c net/netlink/genetlink.c:792 netlink_rcv_skb+0x208/0x3c4 net/netlink/af_netlink.c:2507 genl_rcv+0x38/0x50 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x624/0x8b0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x6e8/0x9cc net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x2e8/0x3d8 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2071 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xcc/0x114 mm/kasan/generic.c:348 insert_work+0x64/0x388 kernel/workqueue.c:1366 __queue_work+0xb30/0x1054 kernel/workqueue.c:1532 queue_work_on+0xc4/0x17c kernel/workqueue.c:1559 queue_work include/linux/workqueue.h:512 [inline] addr_event+0x2f8/0x3f0 drivers/infiniband/core/roce_gid_mgmt.c:853 inet6addr_event+0xa4/0xd8 drivers/infiniband/core/roce_gid_mgmt.c:883 notifier_call_chain kernel/notifier.c:83 [inline] atomic_notifier_call_chain+0x174/0x2a0 kernel/notifier.c:198 inet6addr_notifier_call_chain+0x30/0x40 net/ipv6/addrconf_core.c:109 addrconf_ifdown+0xc78/0x1688 net/ipv6/addrconf.c:3901 addrconf_notify+0x2f4/0xc6c net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2049 [inline] call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] __dev_notify_flags+0x250/0x46c net/core/dev.c:-1 dev_change_flags+0xc8/0x154 net/core/dev.c:8929 do_setlink+0xa20/0x3088 net/core/rtnetlink.c:2779 rtnl_group_changelink net/core/rtnetlink.c:3296 [inline] __rtnl_newlink net/core/rtnetlink.c:3460 [inline] rtnl_newlink+0xb98/0x1404 net/core/rtnetlink.c:3572 rtnetlink_rcv_msg+0x9d4/0xd04 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x208/0x3c4 net/netlink/af_netlink.c:2507 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:5668 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x624/0x8b0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x6e8/0x9cc net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x61c/0x920 net/socket.c:2436 ___sys_sendmsg+0x1d0/0x240 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg net/socket.c:2526 [inline] __arm64_sys_sendmsg+0x1a8/0x254 net/socket.c:2526 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Second to last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xcc/0x114 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3011 [inline] call_rcu+0x114/0x8fc kernel/rcu/tree.c:3091 free_fib_info net/ipv4/fib_semantics.c:255 [inline] fib_info_put include/net/ip_fib.h:579 [inline] fib_release_info+0x554/0x694 net/ipv4/fib_semantics.c:281 fib_table_flush+0x314/0xe00 net/ipv4/fib_trie.c:2066 fib_flush net/ipv4/fib_frontend.c:194 [inline] fib_disable_ip+0xf8/0x174 net/ipv4/fib_frontend.c:1428 fib_netdev_event+0x2e8/0x4c8 net/ipv4/fib_frontend.c:-1 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2049 [inline] call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] dev_close_many+0x2cc/0x440 net/core/dev.c:1650 unregister_netdevice_many+0x3d4/0x17d0 net/core/dev.c:11110 default_device_exit_batch+0x444/0x4a4 net/core/dev.c:11667 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x644/0xa98 net/core/net_namespace.c:635 process_one_work+0x79c/0x1140 kernel/workqueue.c:2310 worker_thread+0x8f4/0x101c kernel/workqueue.c:2457 kthread+0x374/0x454 kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:855 The buggy address belongs to the object at ffff0000db07d400 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 8 bytes to the right of 256-byte region [ffff0000db07d400, ffff0000db07d500) The buggy address belongs to the page: page:00000000e126f58a refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11b07c head:00000000e126f58a order:1 compound_mapcount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 fffffc000333aa80 0000000700000004 ffff0000c0002480 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000db07d400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000db07d480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 06 >ffff0000db07d500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff0000db07d580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000db07d600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== Unable to handle kernel paging request at virtual address dfff80060dcc2d90 Mem abort info: ESR = 0x0000000096000005 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x05: level 1 translation fault Data abort info: ISV = 0, ISS = 0x00000005 CM = 0, WnR = 0 [dfff80060dcc2d90] address between user and kernel address ranges Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 9822 Comm: syz.8.1278 Tainted: G B 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--) pc : ax25_dev_device_down+0x8c/0x67c net/ax25/ax25_dev.c:113 lr : ax25_dev_device_down+0x84/0x67c net/ax25/ax25_dev.c:112 sp : ffff8000208a7030 x29: ffff8000208a7030 x28: ffff8000163d4b00 x27: 000000060dcc2d90 x26: ffff80001b1e4000 x25: 1fffe0001a56946d x24: dfff800000000000 x23: 000000306e616c87 x22: 000000306e616c77 x21: ffff0000d2b4a000 x20: ffff0000d2b4a368 x19: ffff0000db07d400 x18: 0000000000000203 x17: 0000000000000002 x16: ffff8000082d6448 x15: 00000000ffffffff x14: 0000000000ff0100 x13: 0000000000000001 x12: 0000000000080000 x11: 0000000000058437 x10: ffff80002897f000 x9 : ffff80001044e6a4 x8 : 0000000000058438 x7 : 0000000000000000 x6 : 0000000000000001 x5 : ffff8000208a6858 x4 : 0000000000000000 x3 : ffff80001044e6fc x2 : 0000000000000000 x1 : 0000000000000008 x0 : 0000000000000000 Call trace: ax25_dev_device_down+0x8c/0x67c net/ax25/ax25_dev.c:113 ax25_device_event+0x538/0x590 net/ax25/af_ax25.c:144 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2049 [inline] call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] dev_close_many+0x2cc/0x440 net/core/dev.c:1650 dev_close+0x148/0x1f8 net/core/dev.c:1672 bpq_device_event+0x318/0x824 drivers/net/hamradio/bpqether.c:548 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2049 [inline] call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] dev_close_many+0x2cc/0x440 net/core/dev.c:1650 dev_close+0x148/0x1f8 net/core/dev.c:1672 bond_setup_by_slave+0x70/0x318 drivers/net/bonding/bond_main.c:1471 bond_enslave+0x624/0x3014 drivers/net/bonding/bond_main.c:1855 bond_do_ioctl+0x6ec/0xb3c drivers/net/bonding/bond_main.c:4238 bond_siocdevprivate+0x18c/0x1dc drivers/net/bonding/bond_main.c:-1 dev_siocdevprivate net/core/dev_ioctl.c:285 [inline] dev_ifsioc+0xa30/0xef4 net/core/dev_ioctl.c:403 dev_ioctl+0x550/0xc94 net/core/dev_ioctl.c:612 sock_ioctl+0x7e0/0x87c net/socket.c:1184 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Code: 1400001b 9600ab58 910042d7 d343fefb (38786b68) ---[ end trace 1409daf3d7bd1d1e ]--- ---------------- Code disassembly (best guess): 0: 1400001b b 0x6c 4: 9600ab58 bl 0xfffffffff802ad64 8: 910042d7 add x23, x22, #0x10 c: d343fefb lsr x27, x23, #3 * 10: 38786b68 ldrb w8, [x27, x24] <-- trapping instruction