Another NFSv4 KASAN splat, this time from rc3. ================================================================== BUG: KASAN: use-after-free in nfs4_exchange_id_done+0x3d7/0x8e0 [nfsv4] Read of size 8 at addr ffff8804508af528 by task kworker/2:1/34 CPU: 2 PID: 34 Comm: kworker/2:1 Not tainted 4.13.0-rc3-think+ #1 Workqueue: rpciod rpc_async_schedule [sunrpc] Call Trace: dump_stack+0x68/0xa1 print_address_description+0xd9/0x270 kasan_report+0x257/0x370 ? nfs4_exchange_id_done+0x3d7/0x8e0 [nfsv4] check_memory_region+0x13a/0x1a0 __asan_loadN+0xf/0x20 nfs4_exchange_id_done+0x3d7/0x8e0 [nfsv4] ? nfs4_exchange_id_release+0xb0/0xb0 [nfsv4] rpc_exit_task+0x69/0x110 [sunrpc] ? rpc_destroy_wait_queue+0x20/0x20 [sunrpc] ? rpc_destroy_wait_queue+0x20/0x20 [sunrpc] __rpc_execute+0x1a0/0x840 [sunrpc] ? rpc_wake_up_queued_task+0x50/0x50 [sunrpc] ? __lock_is_held+0x9a/0x100 ? debug_lockdep_rcu_enabled.part.16+0x1a/0x30 rpc_async_schedule+0x12/0x20 [sunrpc] process_one_work+0x4d5/0xa70 ? flush_delayed_work+0x70/0x70 ? lock_acquire+0xfc/0x220 worker_thread+0x88/0x630 ? pci_mmcfg_check_reserved+0xc0/0xc0 kthread+0x1a6/0x1f0 ? process_one_work+0xa70/0xa70 ? kthread_create_on_node+0xc0/0xc0 ret_from_fork+0x27/0x40 Allocated by task 1: save_stack_trace+0x1b/0x20 save_stack+0x46/0xd0 kasan_kmalloc+0xad/0xe0 kasan_slab_alloc+0x12/0x20 kmem_cache_alloc+0xe0/0x2f0 getname_flags+0x43/0x220 getname+0x12/0x20 do_sys_open+0x14c/0x2b0 SyS_open+0x1e/0x20 do_syscall_64+0xea/0x260 return_from_SYSCALL_64+0x0/0x7a Freed by task 1: save_stack_trace+0x1b/0x20 save_stack+0x46/0xd0 kasan_slab_free+0x72/0xc0 kmem_cache_free+0xa8/0x300 putname+0x80/0x90 do_sys_open+0x22f/0x2b0 SyS_open+0x1e/0x20 do_syscall_64+0xea/0x260 return_from_SYSCALL_64+0x0/0x7a The buggy address belongs to the object at ffff8804508aeac0\x0a which belongs to the cache names_cache of size 4096 The buggy address is located 2664 bytes inside of\x0a 4096-byte region [ffff8804508aeac0, ffff8804508afac0) The buggy address belongs to the page: page:ffffea0011422a00 count:1 mapcount:0 mapping: (null) index:0x0 [CONT START] compound_mapcount: 0 flags: 0x8000000000008100(slab|head) raw: 8000000000008100 0000000000000000 0000000000000000 0000000100070007 raw: ffffea00113d6020 ffffea001136e220 ffff8804664f8040 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8804508af400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8804508af480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8804508af500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8804508af580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8804508af600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================