================================================================== BUG: KASAN: slab-use-after-free in kobject_uevent_net_broadcast+0x12c/0x560 lib/kobject_uevent.c:415 Read of size 8 at addr ffff88802aeb64d0 by task syz.4.1272/9691 CPU: 1 UID: 0 PID: 9691 Comm: syz.4.1272 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 kobject_uevent_net_broadcast+0x12c/0x560 lib/kobject_uevent.c:415 kobject_uevent_env+0x566/0x9e0 lib/kobject_uevent.c:611 device_del+0x74d/0x8f0 drivers/base/core.c:3983 remove_one_compat_dev drivers/infiniband/core/device.c:1036 [inline] remove_compat_devs drivers/infiniband/core/device.c:1047 [inline] disable_device+0x248/0x330 drivers/infiniband/core/device.c:1339 __ib_unregister_device+0x2c9/0x400 drivers/infiniband/core/device.c:1571 ib_unregister_device_and_put+0xb8/0xf0 drivers/infiniband/core/device.c:1636 nldev_dellink+0x39c/0x430 drivers/infiniband/core/nldev.c:1902 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline] rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] rdma_nl_rcv+0x6ef/0xa40 drivers/infiniband/core/netlink.c:259 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800 __sock_sendmsg net/socket.c:815 [inline] ____sys_sendmsg+0x54e/0x850 net/socket.c:2713 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2767 __sys_sendmsg net/socket.c:2799 [inline] __do_sys_sendmsg net/socket.c:2804 [inline] __se_sys_sendmsg net/socket.c:2802 [inline] __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2802 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f92a299e0d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f92a3887028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f92a2c25fa0 RCX: 00007f92a299e0d9 RDX: 0000000000000004 RSI: 0000200000004680 RDI: 0000000000000004 RBP: 00007f92a2a35024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f92a2c26038 R14: 00007f92a2c25fa0 R15: 00007ffde59de818 Allocated by task 9675: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x321/0x600 mm/slub.c:5563 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] uevent_net_init+0xdb/0x2d0 lib/kobject_uevent.c:782 ops_init+0x35d/0x5d0 net/core/net_namespace.c:137 setup_net+0x118/0x350 net/core/net_namespace.c:450 copy_net_ns+0x4f9/0x720 net/core/net_namespace.c:587 create_new_namespaces+0x3f0/0x6b0 kernel/nsproxy.c:132 unshare_nsproxy_namespaces+0x149/0x190 kernel/nsproxy.c:234 ksys_unshare+0x5a7/0x950 kernel/fork.c:3292 __do_sys_unshare kernel/fork.c:3356 [inline] __se_sys_unshare kernel/fork.c:3354 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3354 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 49: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6499 [inline] kfree+0x1c5/0x650 mm/slub.c:6792 ops_exit_list net/core/net_namespace.c:200 [inline] ops_undo_list+0x43d/0x8d0 net/core/net_namespace.c:253 cleanup_net+0x572/0x810 net/core/net_namespace.c:710 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88802aeb64c0 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 16 bytes inside of freed 32-byte region [ffff88802aeb64c0, ffff88802aeb64e0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802aeb6000 pfn:0x2aeb6 flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000200 ffff88813ff15780 ffffea0000adf890 ffffea0000d31310 raw: ffff88802aeb6000 0000000000400037 00000000f5000000 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1975, tgid 1975 (kworker/u8:5), ts 15482835812 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943 __alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436 alloc_slab_page mm/slub.c:3347 [inline] allocate_slab+0x7d/0x620 mm/slub.c:3462 new_slab mm/slub.c:3513 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7410 refill_sheaf mm/slub.c:2885 [inline] __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4774 alloc_from_pcs mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:4984 [inline] __kmalloc_cache_noprof+0x39b/0x600 mm/slub.c:5559 _kmalloc_noprof include/linux/slab.h:991 [inline] slab_free_hook mm/slub.c:2700 [inline] slab_free mm/slub.c:6499 [inline] kmem_cache_free+0x156/0x650 mm/slub.c:6626 __exit_signal kernel/exit.c:222 [inline] release_task+0xfc5/0x16c0 kernel/exit.c:269 exit_notify kernel/exit.c:809 [inline] do_exit+0x168c/0x2360 kernel/exit.c:1020 call_usermodehelper_exec_async+0x357/0x360 kernel/umh.c:120 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 page last free pid 85 tgid 85 ts 15476704613 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] __free_frozen_pages+0xc93/0xd90 mm/page_alloc.c:2962 __kasan_populate_vmalloc_do mm/kasan/shadow.c:393 [inline] __kasan_populate_vmalloc+0x1a8/0x1c0 mm/kasan/shadow.c:424 kasan_populate_vmalloc include/linux/kasan.h:580 [inline] alloc_vmap_area+0xd1a/0x1420 mm/vmalloc.c:2145 __get_vm_area_node+0x200/0x2f0 mm/vmalloc.c:3248 __vmalloc_node_range_noprof+0x343/0x1540 mm/vmalloc.c:4064 __vmalloc_node_noprof+0xc2/0x100 mm/vmalloc.c:4165 alloc_thread_stack_node kernel/fork.c:359 [inline] dup_task_struct+0x2c6/0xa00 kernel/fork.c:930 copy_process+0x820/0x43e0 kernel/fork.c:2133 kernel_clone+0x2d7/0x940 kernel/fork.c:2766 user_mode_thread+0x115/0x180 kernel/fork.c:2843 call_usermodehelper_exec_work+0x5c/0x230 kernel/umh.c:169 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88802aeb6380: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ffff88802aeb6400: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc >ffff88802aeb6480: 00 00 00 07 fc fc fc fc fa fb fb fb fc fc fc fc ^ ffff88802aeb6500: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc ffff88802aeb6580: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc ==================================================================