syzbot


KCSAN: data-race in do_exit / zap_pid_ns_processes (2)

Status: auto-closed as invalid on 2022/03/10 18:16
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 305d, last: 305d
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_exit / zap_pid_ns_processes 1 579d 579d 0/24 auto-closed as invalid on 2021/06/09 20:04

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

write to 0xffff888125aa4ddc of 4 bytes by task 4824 on cpu 1:
 reparent_leader kernel/exit.c:606 [inline]
 forget_original_parent kernel/exit.c:658 [inline]
 exit_notify kernel/exit.c:674 [inline]
 do_exit+0xb11/0x16a0 kernel/exit.c:826
 do_group_exit+0xa5/0x160 kernel/exit.c:935
 get_signal+0x8cf/0x15d0 kernel/signal.c:2862
 arch_do_signal_or_restart+0x8c/0x2e0 arch/x86/kernel/signal.c:868
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x113/0x190 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
 do_syscall_64+0x50/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888125aa4ddc of 4 bytes by task 4832 on cpu 0:
 thread_group_leader include/linux/sched/signal.h:673 [inline]
 zap_pid_ns_processes+0x39/0x2d0 kernel/pid_namespace.c:171
 find_child_reaper kernel/exit.c:548 [inline]
 forget_original_parent kernel/exit.c:637 [inline]
 exit_notify kernel/exit.c:674 [inline]
 do_exit+0x14ed/0x16a0 kernel/exit.c:826
 __do_sys_exit+0xb/0x10 kernel/exit.c:902
 __se_sys_exit+0x5/0x10 kernel/exit.c:900
 __x64_sys_exit+0x16/0x20 kernel/exit.c:900
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000 -> 0x00000011

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4832 Comm: syz-executor.4 Not tainted 5.17.0-rc2-syzkaller-00060-g88808fbbead4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2022/02/03 18:07 upstream 88808fbbead4 4ebb2798 .config log report info KCSAN: data-race in do_exit / zap_pid_ns_processes
* Struck through repros no longer work on HEAD.