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KCSAN: data-race in do_nanosleep / task_dump_owner (3)

Status: auto-closed as invalid on 2021/01/25 08:51
Subsystems: kernel
[Documentation on labels]
First crash: 1228d, last: 1222d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_nanosleep / task_dump_owner kernel 2 1628d 1644d 0/26 closed as invalid on 2019/11/19 14:54
upstream KCSAN: data-race in do_nanosleep / task_dump_owner (2) kernel 10 1474d 1604d 0/26 auto-closed as invalid on 2020/06/18 13:13

Sample crash report:
==================================================================
BUG: KCSAN: data-race in do_nanosleep / task_dump_owner

read-write to 0xffff888130be202c of 4 bytes by task 12622 on cpu 1:
 freezer_do_not_count include/linux/freezer.h:109 [inline]
 freezable_schedule include/linux/freezer.h:171 [inline]
 do_nanosleep+0xf7/0x3c0 kernel/time/hrtimer.c:1878
 hrtimer_nanosleep kernel/time/hrtimer.c:1931 [inline]
 __do_sys_nanosleep kernel/time/hrtimer.c:1965 [inline]
 __se_sys_nanosleep+0x20b/0x2a0 kernel/time/hrtimer.c:1952
 __x64_sys_nanosleep+0x2d/0x40 kernel/time/hrtimer.c:1952
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888130be202c of 4 bytes by task 12623 on cpu 0:
 task_dump_owner+0x2b/0x1b0 fs/proc/base.c:1823
 pid_update_inode fs/proc/base.c:1965 [inline]
 pid_revalidate+0x69/0x110 fs/proc/base.c:1988
 lookup_fast+0x208/0x370 fs/namei.c:768
 walk_component+0x5c/0x350 fs/namei.c:1857
 link_path_walk+0x451/0x710 fs/namei.c:2180
 path_openat+0x19f/0x20a0 fs/namei.c:3365
 do_filp_open+0xbd/0x1d0 fs/namei.c:3396
 do_sys_openat2+0xa3/0x240 fs/open.c:1172
 do_sys_open fs/open.c:1188 [inline]
 __do_sys_open fs/open.c:1196 [inline]
 __se_sys_open fs/open.c:1192 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1192
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 12623 Comm: syz-executor.0 Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/12/21 08:46 upstream e37b12e4bb21 04201c06 .config console log report info ci2-upstream-kcsan-gce
2020/12/15 18:48 upstream 148842c98a24 f213e07e .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.