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

Status: auto-closed as invalid on 2021/06/11 04:30
Subsystems: kernel
[Documentation on labels]
First crash: 1056d, last: 1056d
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) kernel 3 1342d 1373d 0/26 auto-closed as invalid on 2020/08/28 22:57
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (2) kernel 2 1573d 1574d 0/26 auto-closed as invalid on 2020/02/14 17:46
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me kasan 1 1603d 1603d 0/26 closed as invalid on 2019/11/19 13:54
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (3) kernel 3 1442d 1501d 0/26 auto-closed as invalid on 2020/06/18 14:03
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (5) kernel 1 1250d 1250d 0/26 auto-closed as invalid on 2020/11/28 10:56
upstream KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (6) kernel 1 1196d 1196d 0/26 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):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/05/07 04:22 upstream e48661230cc3 06585184 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me
* Struck through repros no longer work on HEAD.