==================================================================
BUG: KASAN: use-after-free in ax25_fillin_cb_from_dev net/ax25/af_ax25.c:468 [inline]
BUG: KASAN: use-after-free in ax25_fillin_cb+0x394/0x568 net/ax25/af_ax25.c:495
Read of size 4 at addr ffff0000cdff0238 by task syz.7.2363/12927

CPU: 1 PID: 12927 Comm: syz.7.2363 Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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_load4_noabort+0x44/0x50 mm/kasan/report_generic.c:308
 ax25_fillin_cb_from_dev net/ax25/af_ax25.c:468 [inline]
 ax25_fillin_cb+0x394/0x568 net/ax25/af_ax25.c:495
 ax25_setsockopt+0x8d0/0xa5c net/ax25/af_ax25.c:690
 __sys_setsockopt+0x2f8/0x4b0 net/socket.c:2203
 __do_sys_setsockopt net/socket.c:2214 [inline]
 __se_sys_setsockopt net/socket.c:2211 [inline]
 __arm64_sys_setsockopt+0xb8/0xd4 net/socket.c:2211
 __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 4883:
 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]
 kmem_cache_alloc_trace+0x274/0x3fc mm/slub.c:3247
 kmalloc include/linux/slab.h:604 [inline]
 kzalloc include/linux/slab.h:735 [inline]
 ax25_dev_device_up+0x5c/0x540 net/ax25/ax25_dev.c:55
 ax25_device_event+0x504/0x590 net/ax25/af_ax25.c:139
 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
 dev_ifsioc+0x504/0xef4 net/core/dev_ioctl.c:324
 dev_ioctl+0x4d0/0xc94 net/core/dev_ioctl.c:587
 sock_do_ioctl+0x18c/0x240 net/socket.c:1154
 sock_ioctl+0x5c8/0x87c net/socket.c:1257
 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

Freed by task 12718:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4c/0x84 mm/kasan/common.c:46
 kasan_set_free_info+0x28/0x4c mm/kasan/generic.c:360
 ____kasan_slab_free+0x118/0x164 mm/kasan/common.c:366
 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0x128/0x1e8 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kfree+0x170/0x40c mm/slub.c:4559
 ax25_dev_put include/net/ax25.h:302 [inline]
 ax25_release+0x564/0x814 net/ax25/af_ax25.c:1062
 __sock_release net/socket.c:649 [inline]
 sock_close+0xb4/0x1f8 net/socket.c:1336
 __fput+0x1c0/0x7f8 fs/file_table.c:311
 ____fput+0x20/0x30 fs/file_table.c:339
 task_work_run+0x12c/0x1e0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 do_notify_resume+0x24b4/0x3128 arch/arm64/kernel/signal.c:949
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline]
 el0_svc+0xf0/0x1e0 arch/arm64/kernel/entry-common.c:609
 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
 kvfree_call_rcu+0xb8/0x66c kernel/rcu/tree.c:3596
 drop_sysctl_table+0x274/0x39c fs/proc/proc_sysctl.c:1681
 drop_sysctl_table+0x294/0x39c fs/proc/proc_sysctl.c:1684
 unregister_sysctl_table+0x94/0x134 fs/proc/proc_sysctl.c:1719
 unregister_net_sysctl_table+0x20/0x30 net/sysctl_net.c:175
 mpls_dev_sysctl_unregister net/mpls/af_mpls.c:1445 [inline]
 mpls_dev_notify+0x5e0/0x738 net/mpls/af_mpls.c:1671
 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_change_name+0x540/0x7c0 net/core/dev.c:1332
 do_setlink+0x818/0x3088 net/core/rtnetlink.c:2759
 __rtnl_newlink net/core/rtnetlink.c:3450 [inline]
 rtnl_newlink+0x10d0/0x1404 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:2489
 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:5668
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0x60c/0x89c net/netlink/af_netlink.c:1337
 netlink_sendmsg+0x6e8/0x9cc net/netlink/af_netlink.c:1905
 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

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
 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]
 call_usermodehelper_exec+0x22c/0x478 kernel/umh.c:435
 kobject_uevent_env+0x670/0x888 lib/kobject_uevent.c:633
 kobject_uevent+0x2c/0x3c lib/kobject_uevent.c:657
 driver_register+0x29c/0x374 drivers/base/driver.c:248
 usb_register_driver+0x1bc/0x390 drivers/usb/core/driver.c:1061
 rtl8152_driver_init+0x5c/0x74 drivers/net/usb/r8152.c:9928
 do_one_initcall+0x228/0x8b0 init/main.c:1302
 do_initcall_level+0x154/0x214 init/main.c:1375
 do_initcalls+0x58/0xac init/main.c:1391
 do_basic_setup+0x8c/0xa0 init/main.c:1410
 kernel_init_freeable+0x404/0x5fc init/main.c:1615
 kernel_init+0x24/0x1d0 init/main.c:1506
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:855

The buggy address belongs to the object at ffff0000cdff0200
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 56 bytes inside of
 256-byte region [ffff0000cdff0200, ffff0000cdff0300)
The buggy address belongs to the page:
page:0000000052bde711 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10dff0
head:0000000052bde711 order:1 compound_mapcount:0
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000010200 dead000000000100 dead000000000122 ffff0000c0002480
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000cdff0100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000cdff0180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff0000cdff0200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff0000cdff0280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000cdff0300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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