IPVS: ftp: loaded support on port[0] = 21
==================================================================
BUG: KASAN: use-after-free in uprobe_perf_close+0x3e0/0x570 kernel/trace/trace_uprobe.c:1048
Read of size 4 at addr ffff8801ac62830c by task syzkaller523193/4490

CPU: 1 PID: 4490 Comm: syzkaller523193 Not tainted 4.16.0+ #11
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1a7/0x27d lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23c/0x360 mm/kasan/report.c:412
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 uprobe_perf_close+0x3e0/0x570 kernel/trace/trace_uprobe.c:1048
 trace_uprobe_register+0x4cb/0xc00 kernel/trace/trace_uprobe.c:1210
 perf_trace_event_close kernel/trace/trace_event_perf.c:186 [inline]
 perf_uprobe_destroy+0x9b/0x130 kernel/trace/trace_event_perf.c:335
 _free_event+0x3d7/0x11f0 kernel/events/core.c:4445
 put_event+0x35/0x40 kernel/events/core.c:4528
 perf_event_release_kernel+0x6e8/0xfe0 kernel/events/core.c:4634
 perf_release+0x37/0x50 kernel/events/core.c:4644
 __fput+0x327/0x7f0 fs/file_table.c:209
 ____fput+0x15/0x20 fs/file_table.c:243
 task_work_run+0x1ab/0x280 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xa75/0x2700 kernel/exit.c:865
 do_group_exit+0x149/0x400 kernel/exit.c:968
 SYSC_exit_group kernel/exit.c:979 [inline]
 SyS_exit_group+0x1d/0x20 kernel/exit.c:977
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x445c89
RSP: 002b:00007ffe7c691e08 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445c89
RDX: 0000000000445c89 RSI: 0000000000445c89 RDI: 0000000000000001
RBP: 00000000006da018 R08: 0000000000000000 R09: 0000000000406fd0
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000406f40
R13: 0000000000406fd0 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 4490:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:552
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489
 kmem_cache_alloc_node+0x144/0x760 mm/slab.c:3632
 alloc_task_struct_node kernel/fork.c:157 [inline]
 dup_task_struct kernel/fork.c:770 [inline]
 copy_process.part.38+0x1ab9/0x6140 kernel/fork.c:1631
 copy_process kernel/fork.c:1606 [inline]
 _do_fork+0x1f7/0xfa0 kernel/fork.c:2087
 SYSC_clone kernel/fork.c:2194 [inline]
 SyS_clone+0x37/0x50 kernel/fork.c:2188
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 0:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:520
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:527
 __cache_free mm/slab.c:3486 [inline]
 kmem_cache_free+0x83/0x2a0 mm/slab.c:3744
 free_task_struct kernel/fork.c:162 [inline]
 free_task+0x155/0x1b0 kernel/fork.c:391
 __put_task_struct+0x24b/0x3e0 kernel/fork.c:657
 put_task_struct include/linux/sched/task.h:96 [inline]
 delayed_put_task_struct+0xd8/0x3e0 kernel/exit.c:180
 __rcu_reclaim kernel/rcu/rcu.h:178 [inline]
 rcu_do_batch kernel/rcu/tree.c:2675 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2930 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2897 [inline]
 rcu_process_callbacks+0xd6c/0x17b0 kernel/rcu/tree.c:2914
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285

The buggy address belongs to the object at ffff8801ac6282c0
 which belongs to the cache task_struct of size 6016
The buggy address is located 76 bytes inside of
 6016-byte region [ffff8801ac6282c0, ffff8801ac629a40)
The buggy address belongs to the page:
page:ffffea0006b18a00 count:1 mapcount:0 mapping:ffff8801ac6282c0 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801ac6282c0 0000000000000000 0000000100000001
raw: ffffea0006ae0c20 ffff8801dad0c248 ffff8801dad46200 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801ac628200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801ac628280: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
>ffff8801ac628300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff8801ac628380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801ac628400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================