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KCSAN: data-race in __ptrace_unlink / do_exit (3)

Status: auto-closed as invalid on 2021/01/27 14:46
Subsystems: kernel
[Documentation on labels]
First crash: 1191d, last: 1191d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __ptrace_unlink / do_exit kernel 4 1312d 1365d 0/26 auto-closed as invalid on 2020/09/28 07:37
upstream KCSAN: data-race in __ptrace_unlink / do_exit (2) kernel 4 1238d 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 1062d 0/26 auto-closed as invalid on 2021/06/15 19:49
upstream KCSAN: data-race in __ptrace_unlink / do_exit (6) kernel 7 878d 977d 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 0xffff88802fd8a030 of 4 bytes by task 4144 on cpu 0:
 __ptrace_unlink+0x162/0x2f0 kernel/ptrace.c:132
 __ptrace_detach+0x1b/0x1a0 kernel/ptrace.c:522
 exit_ptrace+0x93/0x160 kernel/ptrace.c:582
 forget_original_parent kernel/exit.c:627 [inline]
 exit_notify kernel/exit.c:667 [inline]
 do_exit+0x1219/0x1630 kernel/exit.c:843
 do_group_exit+0xc8/0x170 kernel/exit.c:920
 get_signal+0xd5e/0x1440 kernel/signal.c:2770
 arch_do_signal_or_restart+0x2a/0x270 arch/x86/kernel/signal.c:811
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x109/0x1a0 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88802fd8a030 of 4 bytes by task 4140 on cpu 1:
 ptrace_event_enabled include/linux/ptrace.h:142 [inline]
 ptrace_event include/linux/ptrace.h:157 [inline]
 do_exit+0xff/0x1630 kernel/exit.c:764
 do_group_exit+0xc8/0x170 kernel/exit.c:920
 get_signal+0xd5e/0x1440 kernel/signal.c:2770
 arch_do_signal_or_restart+0x2a/0x270 arch/x86/kernel/signal.c:811
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x109/0x1a0 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 4140 Comm: syz-executor.5 Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/12/23 14:43 upstream 614cb5894306 c2c1d1dd .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.