================================================================== BUG: KASAN: use-after-free in ax25_release+0x5ca/0x870 net/ax25/af_ax25.c:1061 Read of size 8 at addr ffff88801b5e2508 by task syz.4.106/4654 CPU: 0 PID: 4654 Comm: syz.4.106 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x230 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 ax25_release+0x5ca/0x870 net/ax25/af_ax25.c:1061 __sock_release net/socket.c:649 [inline] sock_close+0xd5/0x240 net/socket.c:1336 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fcc53842be9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffcb6c778e8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fcc53a6bda0 RCX: 00007fcc53842be9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fcc53a6bda0 R08: 00000000000001d4 R09: 00000018b6c77bdf R10: 00007fcc53a6bcb0 R11: 0000000000000246 R12: 0000000000019cc6 R13: 00007ffcb6c779e0 R14: ffffffffffffffff R15: 00007ffcb6c77a00 Allocated by task 4660: 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:604 [inline] kzalloc include/linux/slab.h:735 [inline] ax25_dev_device_up+0x50/0x580 net/ax25/ax25_dev.c:55 ax25_device_event+0x483/0x4f0 net/ax25/af_ax25.c:139 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+0x178/0x2d0 net/core/dev.c:-1 dev_change_flags+0xe3/0x1a0 net/core/dev.c:8929 dev_ifsioc+0x147/0xe70 net/core/dev_ioctl.c:324 dev_ioctl+0x55f/0xe50 net/core/dev_ioctl.c:587 sock_do_ioctl+0x222/0x2f0 net/socket.c:1154 sock_ioctl+0x4ed/0x6e0 net/socket.c:1257 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 4660: 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:1705 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0xef/0x2a0 mm/slub.c:4559 ax25_device_event+0x4b4/0x4f0 net/ax25/af_ax25.c:144 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+0x178/0x2d0 net/core/dev.c:-1 dev_change_flags+0xe3/0x1a0 net/core/dev.c:8929 dev_ifsioc+0x147/0xe70 net/core/dev_ioctl.c:324 dev_ioctl+0x55f/0xe50 net/core/dev_ioctl.c:587 sock_do_ioctl+0x222/0x2f0 net/socket.c:1154 sock_ioctl+0x4ed/0x6e0 net/socket.c:1257 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 queue_work_on+0x11d/0x1d0 kernel/workqueue.c:1559 queue_work include/linux/workqueue.h:512 [inline] netdevice_queue_work drivers/infiniband/core/roce_gid_mgmt.c:659 [inline] netdevice_event+0x803/0x900 drivers/infiniband/core/roce_gid_mgmt.c:802 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+0x1275/0x16b0 net/core/dev.c:10428 __ip_tunnel_create+0x2bf/0x380 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x232/0x6b0 net/ipv4/ip_tunnel.c:1098 ops_init+0x357/0x600 net/core/net_namespace.c:138 setup_net+0x38d/0x9f0 net/core/net_namespace.c:333 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x116/0x160 kernel/nsproxy.c:226 ksys_unshare+0x4bc/0x890 kernel/fork.c:3175 __do_sys_unshare kernel/fork.c:3249 [inline] __se_sys_unshare kernel/fork.c:3247 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3247 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 The buggy address belongs to the object at ffff88801b5e2500 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 8 bytes inside of 192-byte region [ffff88801b5e2500, ffff88801b5e25c0) The buggy address belongs to the page: page:ffffea00006d7880 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1b5e2 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea00006b6b40 0000000800000004 ffff888016841a00 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, ts 2293041417, free_ts 0 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5474 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2031 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1975 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc_trace+0x1a5/0x2a0 mm/slub.c:3245 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:735 [inline] kset_create lib/kobject.c:982 [inline] kset_create_and_add+0x56/0x160 lib/kobject.c:1025 bus_register+0x363/0x6c0 drivers/base/bus.c:816 vdpa_init+0x13/0x70 drivers/vdpa/vdpa.c:669 do_one_initcall+0x1ee/0x680 init/main.c:1302 do_initcall_level+0x137/0x1f0 init/main.c:1375 do_initcalls+0x4b/0x90 init/main.c:1391 kernel_init_freeable+0x3ce/0x560 init/main.c:1615 kernel_init+0x19/0x1b0 init/main.c:1506 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 page_owner free stack trace missing Memory state around the buggy address: ffff88801b5e2400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88801b5e2480: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801b5e2500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801b5e2580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88801b5e2600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================