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BUG: KASAN: use-after-free in uprobe_perf_close+0x467/0x600 kernel/trace/trace_uprobe.c:1031
Read of size 4 at addr ffff8801913f65a4 by task syz-executor4/17181

CPU: 0 PID: 17181 Comm: syz-executor4 Not tainted 4.18.0+ #189
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+0x1c9/0x2b4 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 uprobe_perf_close+0x467/0x600 kernel/trace/trace_uprobe.c:1031
 trace_uprobe_register+0x305/0xcf0 kernel/trace/trace_uprobe.c:1215
 perf_trace_event_close kernel/trace/trace_event_perf.c:186 [inline]
 perf_uprobe_destroy+0xa0/0x130 kernel/trace/trace_event_perf.c:339
 _free_event+0x414/0x15e0 kernel/events/core.c:4445
 free_event+0xb4/0x180 kernel/events/core.c:4472
 perf_event_release_kernel+0x7d5/0xfc0 kernel/events/core.c:4633
 perf_release+0x37/0x50 kernel/events/core.c:4647
 __fput+0x39b/0x860 fs/file_table.c:251
 ____fput+0x15/0x20 fs/file_table.c:282
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x1b25/0x2760 kernel/exit.c:865
 do_group_exit+0x177/0x440 kernel/exit.c:968
 get_signal+0x88e/0x1970 kernel/signal.c:2468
 do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816
 exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162
 prepare_exit_to_usermode+0x342/0x3b0 arch/x86/entry/common.c:197
 retint_user+0x8/0x18
RIP: 0033:0x457095
Code: Bad RIP value.
RSP: 002b:0000000020000040 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fb24f1846d4 RCX: 0000000000457089
RDX: 0000000020000100 RSI: 0000000020000040 RDI: 0002001000000000
RBP: 00000000009300a0 R08: 0000000020000080 R09: 0000000000000000
R10: 0000000020000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004cb268 R14: 00000000004c3092 R15: 0000000000000000

Allocated by task 17168:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
 kmem_cache_alloc_node+0x144/0x780 mm/slab.c:3644
 alloc_task_struct_node kernel/fork.c:157 [inline]
 dup_task_struct kernel/fork.c:802 [inline]
 copy_process.part.35+0x16fb/0x7140 kernel/fork.c:1669
 copy_process kernel/fork.c:1644 [inline]
 _do_fork+0x291/0x12a0 kernel/fork.c:2127
 __do_sys_clone kernel/fork.c:2234 [inline]
 __se_sys_clone kernel/fork.c:2228 [inline]
 __x64_sys_clone+0xbf/0x150 kernel/fork.c:2228
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 17168:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kmem_cache_free+0x86/0x2d0 mm/slab.c:3756
 free_task_struct kernel/fork.c:162 [inline]
 free_task+0x16e/0x1f0 kernel/fork.c:415
 copy_process.part.35+0x160f/0x7140 kernel/fork.c:2062
 copy_process kernel/fork.c:1644 [inline]
 _do_fork+0x291/0x12a0 kernel/fork.c:2127
 __do_sys_clone kernel/fork.c:2234 [inline]
 __se_sys_clone kernel/fork.c:2228 [inline]
 __x64_sys_clone+0xbf/0x150 kernel/fork.c:2228
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801913f6580
 which belongs to the cache task_struct(49:syz4) of size 5952
The buggy address is located 36 bytes inside of
 5952-byte region [ffff8801913f6580, ffff8801913f7cc0)
The buggy address belongs to the page:
page:ffffea000644fd80 count:1 mapcount:0 mapping:ffff8801d8374040 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffffea0006c9e088 ffffea000662e608 ffff8801d8374040
raw: 0000000000000000 ffff8801913f6580 0000000100000001 ffff8801b0626800
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff8801b0626800

Memory state around the buggy address:
 ffff8801913f6480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801913f6500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8801913f6580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff8801913f6600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801913f6680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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