syzbot


KCSAN: data-race in do_settimeofday64 / ktime_get_real_seconds (2)

Status: auto-closed as invalid on 2021/01/01 01:41
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+e5abc53c8a8988263acc@syzkaller.appspotmail.com
First crash: 1402d, last: 1246d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_settimeofday64 / ktime_get_real_seconds (4) kernel 34 925d 1123d 0/26 auto-closed as invalid on 2021/11/18 03:13
upstream KCSAN: data-race in do_settimeofday64 / ktime_get_real_seconds (3) kernel 4 1181d 1211d 0/26 auto-closed as invalid on 2021/03/06 23:28
upstream KCSAN: data-race in do_settimeofday64 / ktime_get_real_seconds kernel 1 1423d 1423d 0/26 closed as invalid on 2020/06/18 14:13

Sample crash report:
==================================================================
BUG: KCSAN: data-race in do_settimeofday64 / ktime_get_real_seconds

write to 0xffffffff882f98f8 of 8 bytes by task 11634 on cpu 1:
 tk_set_xtime kernel/time/timekeeping.c:138 [inline]
 do_settimeofday64+0x3cb/0x550 kernel/time/timekeeping.c:1323
 do_sys_settimeofday64+0x17b/0x1a0 kernel/time/time.c:195
 posix_clock_realtime_set+0x13/0x20 kernel/time/posix-timers.c:185
 __do_sys_clock_settime kernel/time/posix-timers.c:1079 [inline]
 __se_sys_clock_settime kernel/time/posix-timers.c:1067 [inline]
 __x64_sys_clock_settime+0x136/0x160 kernel/time/posix-timers.c:1067
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffffffff882f98f8 of 8 bytes by task 11629 on cpu 0:
 ktime_get_real_seconds+0x11/0x20 kernel/time/timekeeping.c:1013
 recently_deleted fs/ext4/ialloc.c:703 [inline]
 find_inode_bit+0x231/0x3a0 fs/ext4/ialloc.c:728
 __ext4_new_inode+0xd22/0x3060 fs/ext4/ialloc.c:1062
 ext4_symlink+0x2bc/0x770 fs/ext4/namei.c:3336
 vfs_symlink+0x216/0x2d0 fs/namei.c:3960
 do_symlinkat+0xee/0x280 fs/namei.c:3987
 __do_sys_symlink fs/namei.c:4006 [inline]
 __se_sys_symlink fs/namei.c:4004 [inline]
 __x64_sys_symlink+0x32/0x40 fs/namei.c:4004
 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: 11629 Comm: syz-executor.3 Not tainted 5.10.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (15):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/11/27 01:40 upstream 4df910620beb 5018c946 .config console log report info ci2-upstream-kcsan-gce
2020/11/17 15:53 upstream 9c87c9f41245 bd2a760b .config console log report info ci2-upstream-kcsan-gce
2020/11/15 21:58 upstream 0062442ecfef 1bf9a662 .config console log report info ci2-upstream-kcsan-gce
2020/10/30 13:23 upstream 07e088730245 a6e3ac3b .config console log report info ci2-upstream-kcsan-gce
2020/10/16 07:46 upstream 726eb70e0d34 6e262c73 .config console log report info ci2-upstream-kcsan-gce
2020/09/16 21:42 upstream 5925fa68fe82 77507d02 .config console log report info ci2-upstream-kcsan-gce
2020/09/10 10:09 upstream 7fe10096c150 ac7ca78e .config console log report ci2-upstream-kcsan-gce
2020/09/02 15:11 upstream 9c7d619be5a0 abf9ba4f .config console log report ci2-upstream-kcsan-gce
2020/07/30 10:37 upstream 83bdc7275e62 b0947553 .config console log report ci2-upstream-kcsan-gce
2020/07/20 11:48 upstream 5714ee50bb43 8caeeeb7 .config console log report ci2-upstream-kcsan-gce
2020/07/16 13:49 upstream f8456690ba8e b090c643 .config console log report ci2-upstream-kcsan-gce
2020/07/01 08:14 upstream 7c30b859a947 c0383ebe .config console log report ci2-upstream-kcsan-gce
2020/06/29 16:13 upstream 9ebcfadb0610 ce9ef6f2 .config console log report ci2-upstream-kcsan-gce
2020/06/28 11:14 upstream 719fdd32921f a2cdad9d .config console log report ci2-upstream-kcsan-gce
2020/06/24 13:09 upstream 3e08a95294a4 41694dbf .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.