syzbot


KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (7)

Status: auto-closed as invalid on 2021/06/11 04:30
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 460d, last: 460d
similar bugs (6):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (4) 3 747d 778d 0/23 auto-closed as invalid on 2020/08/28 22:57
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (2) 2 978d 979d 0/23 auto-closed as invalid on 2020/02/14 17:46
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me 1 1008d 1008d 0/23 closed as invalid on 2019/11/19 13:54
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (3) 3 847d 906d 0/23 auto-closed as invalid on 2020/06/18 14:03
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (5) 1 655d 655d 0/23 auto-closed as invalid on 2020/11/28 10:56
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (6) 1 601d 601d 0/23 auto-closed as invalid on 2021/01/21 10:32

Sample crash report:
==================================================================
BUG: KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me

write to 0xffff8881241fe0ac of 4 bytes by task 7374 on cpu 1:
 freezer_count include/linux/freezer.h:121 [inline]
 freezable_schedule include/linux/freezer.h:173 [inline]
 futex_wait_queue_me+0x1ba/0x260 kernel/futex.c:2606
 futex_wait_requeue_pi kernel/futex.c:3223 [inline]
 do_futex+0x187b/0x1ee0 kernel/futex.c:3753
 __do_sys_futex kernel/futex.c:3796 [inline]
 __se_sys_futex+0x2a8/0x390 kernel/futex.c:3762
 __x64_sys_futex+0x74/0x80 kernel/futex.c:3762
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881241fe0ac of 4 bytes by task 7385 on cpu 0:
 attach_to_pi_owner+0x64/0x530 kernel/futex.c:1234
 lookup_pi_state kernel/futex.c:1321 [inline]
 futex_requeue+0xbc8/0x1620 kernel/futex.c:2058
 do_futex+0x1227/0x1ee0 kernel/futex.c:3756
 __do_sys_futex kernel/futex.c:3796 [inline]
 __se_sys_futex+0x2a8/0x390 kernel/futex.c:3762
 __x64_sys_futex+0x74/0x80 kernel/futex.c:3762
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7385 Comm: syz-executor.3 Not tainted 5.12.0-syzkaller #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 2021/05/07 04:22 upstream e48661230cc3 06585184 .config log report info KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me