================================================================== BUG: KASAN: use-after-free in instrument_atomic_write include/linux/instrumented.h:71 [inline] BUG: KASAN: use-after-free in atomic_dec_return include/asm-generic/atomic-instrumented.h:340 [inline] BUG: KASAN: use-after-free in rxrpc_put_bundle+0x1d/0x80 net/rxrpc/conn_client.c:141 Write of size 4 at addr ffff8880a6245120 by task ksoftirqd/0/9 CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.9.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x198/0x1fd lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 check_memory_region_inline mm/kasan/generic.c:186 [inline] check_memory_region+0x13d/0x180 mm/kasan/generic.c:192 instrument_atomic_write include/linux/instrumented.h:71 [inline] atomic_dec_return include/asm-generic/atomic-instrumented.h:340 [inline] rxrpc_put_bundle+0x1d/0x80 net/rxrpc/conn_client.c:141 rxrpc_destroy_connection+0x150/0x2f0 net/rxrpc/conn_object.c:367 rcu_do_batch kernel/rcu/tree.c:2428 [inline] rcu_core+0x5ca/0x1130 kernel/rcu/tree.c:2656 __do_softirq+0x1f8/0xb23 kernel/softirq.c:298 run_ksoftirqd kernel/softirq.c:652 [inline] run_ksoftirqd+0xcf/0x170 kernel/softirq.c:644 smpboot_thread_fn+0x655/0x9e0 kernel/smpboot.c:165 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Allocated by task 17544: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 kmem_cache_alloc_trace+0x174/0x300 mm/slab.c:3550 kmalloc include/linux/slab.h:554 [inline] kzalloc include/linux/slab.h:666 [inline] rxrpc_alloc_bundle+0x88/0x2c0 net/rxrpc/conn_client.c:121 rxrpc_look_up_bundle net/rxrpc/conn_client.c:275 [inline] rxrpc_prep_call net/rxrpc/conn_client.c:374 [inline] rxrpc_connect_call+0x85c/0x1580 net/rxrpc/conn_client.c:710 rxrpc_new_client_call+0x961/0x1020 net/rxrpc/call_object.c:331 rxrpc_new_client_call_for_sendmsg net/rxrpc/sendmsg.c:622 [inline] rxrpc_do_sendmsg+0xf14/0x136d net/rxrpc/sendmsg.c:679 rxrpc_sendmsg+0x420/0x630 net/rxrpc/af_rxrpc.c:560 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2353 ___sys_sendmsg+0xf3/0x170 net/socket.c:2407 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2440 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 8206: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422 __cache_free mm/slab.c:3418 [inline] kfree+0x10e/0x2b0 mm/slab.c:3756 rxrpc_put_bundle net/rxrpc/conn_client.c:146 [inline] rxrpc_put_bundle+0x6b/0x80 net/rxrpc/conn_client.c:138 rxrpc_unbundle_conn+0x1f8/0x3d0 net/rxrpc/conn_client.c:935 rxrpc_clean_up_local_conns+0x38d/0x587 net/rxrpc/conn_client.c:1114 rxrpc_local_destroyer net/rxrpc/local_object.c:399 [inline] rxrpc_local_processor+0x38d/0x5e0 net/rxrpc/local_object.c:433 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Last call_rcu(): kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_record_aux_stack+0x82/0xb0 mm/kasan/generic.c:346 __call_rcu kernel/rcu/tree.c:2894 [inline] call_rcu+0x15e/0x7c0 kernel/rcu/tree.c:2968 neigh_parms_release net/core/neighbour.c:1662 [inline] neigh_parms_release+0x1e3/0x260 net/core/neighbour.c:1652 inetdev_destroy net/ipv4/devinet.c:325 [inline] inetdev_event+0xca6/0x14fd net/ipv4/devinet.c:1599 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2034 call_netdevice_notifiers_extack net/core/dev.c:2046 [inline] call_netdevice_notifiers net/core/dev.c:2060 [inline] rollback_registered_many+0x97f/0x1550 net/core/dev.c:9346 rollback_registered net/core/dev.c:9391 [inline] unregister_netdevice_queue+0x2dd/0x570 net/core/dev.c:10480 unregister_netdevice include/linux/netdevice.h:2798 [inline] __tun_detach+0x105a/0x13d0 drivers/net/tun.c:673 tun_detach drivers/net/tun.c:690 [inline] tun_chr_close+0xd9/0x180 drivers/net/tun.c:3390 __fput+0x285/0x920 fs/file_table.c:281 task_work_run+0xdd/0x190 kernel/task_work.c:141 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:165 [inline] exit_to_user_mode_prepare+0x1e1/0x200 kernel/entry/common.c:192 syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:267 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8880a6245100 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 32 bytes inside of 192-byte region [ffff8880a6245100, ffff8880a62451c0) The buggy address belongs to the page: page:0000000088bb06ba refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880a6245d00 pfn:0xa6245 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea000278d848 ffffea00029b6dc8 ffff8880aa040000 raw: ffff8880a6245d00 ffff8880a6245000 000000010000000f 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a6245000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880a6245080: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff8880a6245100: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a6245180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880a6245200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================