KCSAN: data-race in do_group_exit / mm_release

Status: auto-closed as invalid on 2020/08/30 02:37
Subsystems: kernel
[Documentation on labels]
First crash: 2211d, last: 2211d
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_group_exit / mm_release (2) kernel 6 1 2135d 2135d 0/29 auto-closed as invalid on 2020/11/13 23:31
upstream KCSAN: data-race in do_group_exit / mm_release (3) kernel 6 1 2098d 2077d 0/29 auto-closed as invalid on 2020/12/21 16:29

Sample crash report:
==================================================================
BUG: KCSAN: data-race in do_group_exit / mm_release

write to 0xffff888098ae84b4 of 4 bytes by task 24022 on cpu 1:
 do_group_exit+0x137/0x180 kernel/exit.c:897
 __do_sys_exit_group+0xb/0x10 kernel/exit.c:914
 __se_sys_exit_group+0x5/0x10 kernel/exit.c:912
 __x64_sys_exit_group+0x16/0x20 kernel/exit.c:912
 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:384
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888098ae84b4 of 4 bytes by task 24029 on cpu 0:
 mm_release+0x7f/0x190 kernel/fork.c:1313
 exit_mm_release+0x21/0x30 kernel/fork.c:1337
 exit_mm+0x4b/0x330 kernel/exit.c:437
 do_exit+0x415/0x16e0 kernel/exit.c:792
 __do_sys_exit+0xb/0x10 kernel/exit.c:872
 __se_sys_exit+0x5/0x10 kernel/exit.c:870
 __x64_sys_exit+0x16/0x20 kernel/exit.c:870
 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:384
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 24029 Comm: syz-executor.2 Not tainted 5.8.0-rc6-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
2020/07/26 02:29 upstream 04300d66f0a0 1f7cc1ca .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.