syzbot


KCSAN: data-race in __do_munmap / acct_account_cputime (2)

Status: auto-closed as invalid on 2021/10/30 20:08
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 488d, last: 426d
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __do_munmap / acct_account_cputime 5 530d 587d 0/24 auto-closed as invalid on 2021/07/19 08:47

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __do_munmap / acct_account_cputime

write to 0xffff8881352197c0 of 8 bytes by task 2998 on cpu 1:
 vm_stat_account mm/mmap.c:3335 [inline]
 remove_vma_list mm/mmap.c:2628 [inline]
 __do_munmap+0xf94/0x1340 mm/mmap.c:2887
 do_munmap mm/mmap.c:2895 [inline]
 munmap_vma_range mm/mmap.c:603 [inline]
 mmap_region+0x58a/0x1260 mm/mmap.c:1742
 do_mmap+0x781/0xc20 mm/mmap.c:1575
 vm_mmap_pgoff+0x117/0x1f0 mm/util.c:519
 ksys_mmap_pgoff+0x284/0x350 mm/mmap.c:1624
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881352197c0 of 8 bytes by interrupt on cpu 0:
 __acct_update_integrals kernel/tsacct.c:140 [inline]
 acct_account_cputime+0x15a/0x1a0 kernel/tsacct.c:164
 update_process_times+0x5c/0x150 kernel/time/timer.c:1783
 tick_sched_handle kernel/time/tick-sched.c:226 [inline]
 tick_sched_timer+0x191/0x210 kernel/time/tick-sched.c:1421
 __run_hrtimer+0x160/0x480 kernel/time/hrtimer.c:1685
 __hrtimer_run_queues kernel/time/hrtimer.c:1749 [inline]
 hrtimer_interrupt+0x380/0xaf0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x6f/0x1c0 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x64/0x80 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 console_unlock+0x979/0xbb0 kernel/printk/printk.c:2715
 vprintk_emit+0xd9/0x390 kernel/printk/printk.c:2244
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2255
 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50
 _printk+0x76/0x97 kernel/printk/printk.c:2265
 __ext4_msg+0x124/0x130 fs/ext4/super.c:914
 parse_options+0x1587/0x1890 fs/ext4/super.c:2438
 ext4_fill_super+0x15ce/0x7840 fs/ext4/super.c:4151
 mount_bdev+0x1e8/0x290 fs/super.c:1368
 ext4_mount+0x2d/0x40 fs/ext4/super.c:6506
 legacy_get_tree+0x70/0xc0 fs/fs_context.c:610
 vfs_get_tree+0x4a/0x1a0 fs/super.c:1498
 do_new_mount fs/namespace.c:2988 [inline]
 path_mount+0x11ec/0x1d20 fs/namespace.c:3318
 do_mount fs/namespace.c:3331 [inline]
 __do_sys_mount fs/namespace.c:3539 [inline]
 __se_sys_mount+0x24b/0x2f0 fs/namespace.c:3516
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3516
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000005492 -> 0x000000000000540a

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 2964 Comm: syz-executor.1 Tainted: G        W         5.15.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (6):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/09/25 19:59 upstream 85736168463d 8cac236e .config log report info KCSAN: data-race in __do_munmap / acct_account_cputime
ci2-upstream-kcsan-gce 2021/09/10 18:03 upstream bf9f243f23e6 5ae8508a .config log report info KCSAN: data-race in __do_munmap / acct_account_cputime
ci2-upstream-kcsan-gce 2021/08/09 18:01 upstream 36a21d51725a 6972b106 .config log report info KCSAN: data-race in __do_munmap / acct_account_cputime
ci2-upstream-kcsan-gce 2021/08/06 09:33 upstream 902e7f373fff 2f537099 .config log report info KCSAN: data-race in __do_munmap / acct_account_cputime
ci2-upstream-kcsan-gce 2021/08/04 07:30 upstream d5ad8ec3cfb5 6c236867 .config log report info KCSAN: data-race in __do_munmap / acct_account_cputime
ci2-upstream-kcsan-gce 2021/07/26 04:49 upstream ff1176468d36 4d1b57d4 .config log report info KCSAN: data-race in __do_munmap / acct_account_cputime
* Struck through repros no longer work on HEAD.