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KCSAN: data-race in __ptrace_unlink / do_exit

Status: auto-closed as invalid on 2020/09/28 07:37
Subsystems: kernel
[Documentation on labels]
First crash: 1365d, last: 1313d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __ptrace_unlink / do_exit (3) kernel 1 1191d 1191d 0/26 auto-closed as invalid on 2021/01/27 14:46
upstream KCSAN: data-race in __ptrace_unlink / do_exit (2) kernel 4 1239d 1207d 0/26 auto-closed as invalid on 2020/12/21 11:46
upstream KCSAN: data-race in __ptrace_unlink / do_exit (5) kernel 2 1052d 1063d 0/26 auto-closed as invalid on 2021/06/15 19:49
upstream KCSAN: data-race in __ptrace_unlink / do_exit (6) kernel 7 879d 978d 0/26 auto-closed as invalid on 2021/12/06 01:33
upstream KCSAN: data-race in __ptrace_unlink / do_exit (4) kernel 1 1131d 1131d 0/26 auto-closed as invalid on 2021/03/28 11:03

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __ptrace_unlink / do_exit

write to 0xffff88811dc1c028 of 4 bytes by task 32671 on cpu 1:
 __ptrace_unlink+0x160/0x300 kernel/ptrace.c:132
 __ptrace_detach+0x1b/0x1a0 kernel/ptrace.c:528
 exit_ptrace+0x93/0x160 kernel/ptrace.c:588
 forget_original_parent kernel/exit.c:610 [inline]
 exit_notify kernel/exit.c:650 [inline]
 do_exit+0x13d1/0x16c0 kernel/exit.c:826
 do_group_exit+0xcb/0x180 kernel/exit.c:903
 get_signal+0xe9f/0x1650 kernel/signal.c:2757
 arch_do_signal+0x25/0x270 arch/x86/kernel/signal.c:811
 exit_to_user_mode_loop kernel/entry/common.c:136 [inline]
 exit_to_user_mode_prepare+0x124/0x210 kernel/entry/common.c:167
 syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:242
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88811dc1c028 of 4 bytes by task 32708 on cpu 0:
 ptrace_event_enabled include/linux/ptrace.h:142 [inline]
 ptrace_event include/linux/ptrace.h:157 [inline]
 do_exit+0x13c/0x16c0 kernel/exit.c:747
 do_group_exit+0xcb/0x180 kernel/exit.c:903
 get_signal+0xe9f/0x1650 kernel/signal.c:2757
 arch_do_signal+0x25/0x270 arch/x86/kernel/signal.c:811
 exit_to_user_mode_loop kernel/entry/common.c:136 [inline]
 exit_to_user_mode_prepare+0x124/0x210 kernel/entry/common.c:167
 syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:242
 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:287

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 32708 Comm: syz-executor.0 Not tainted 5.9.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/08/24 07:34 upstream cb95712138ec cef5ae68 .config console log report ci2-upstream-kcsan-gce
2020/08/01 03:47 upstream 7dc6fd0f3b84 8df85ed9 .config console log report ci2-upstream-kcsan-gce
2020/07/08 13:39 upstream dcde237b9b0e 5962a2dc .config console log report ci2-upstream-kcsan-gce
2020/07/02 11:49 upstream cd77006e01b3 f30c14bf .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.