syzbot


KCSAN: data-race in munlock_vma_pages_range / try_to_unmap_one
Status: auto-closed as invalid on 2020/03/10 21:44
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 876d, last: 876d
similar bugs (6):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in munlock_vma_pages_range / try_to_unmap_one (6) 2 490d 513d 0/22 auto-closed as invalid on 2021/02/24 23:17
upstream KCSAN: data-race in munlock_vma_pages_range / try_to_unmap_one (4) 2 615d 631d 0/22 auto-closed as invalid on 2020/10/22 10:22
upstream KCSAN: data-race in munlock_vma_pages_range / try_to_unmap_one (3) 2 675d 694d 0/22 auto-closed as invalid on 2020/08/23 10:47
upstream KCSAN: data-race in munlock_vma_pages_range / try_to_unmap_one (5) 1 578d 578d 0/22 auto-closed as invalid on 2020/11/28 11:46
upstream KCSAN: data-race in munlock_vma_pages_range / try_to_unmap_one (7) 3 372d 387d 0/22 auto-closed as invalid on 2021/06/22 19:33
upstream KCSAN: data-race in munlock_vma_pages_range / try_to_unmap_one (2) 1 791d 791d 0/22 auto-closed as invalid on 2020/06/03 05:11

Sample crash report:
==================================================================
BUG: KCSAN: data-race in munlock_vma_pages_range / try_to_unmap_one

write to 0xffff8880a7afe500 of 8 bytes by task 18773 on cpu 1:
 munlock_vma_pages_range+0x59/0x790 mm/mlock.c:448
 munlock_vma_pages_all mm/internal.h:306 [inline]
 exit_mmap+0x24f/0x300 mm/mmap.c:3124
 __mmput kernel/fork.c:1082 [inline]
 mmput+0xea/0x280 kernel/fork.c:1103
 exit_mm kernel/exit.c:485 [inline]
 do_exit+0x4ac/0x18c0 kernel/exit.c:784
 do_group_exit+0xb4/0x1c0 kernel/exit.c:895
 get_signal+0x2a2/0x1320 kernel/signal.c:2734
 do_signal+0x2f/0x6c0 arch/x86/kernel/signal.c:815
 exit_to_usermode_loop+0x250/0x2c0 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:278 [inline]
 do_syscall_64+0x384/0x3a0 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880a7afe500 of 8 bytes by task 18724 on cpu 0:
 try_to_unmap_one+0x105/0x16f0 mm/rmap.c:1382
 rmap_walk_file+0x23c/0x590 mm/rmap.c:1920
 rmap_walk+0x118/0x190 mm/rmap.c:1938
 try_to_munlock+0x8b/0xb0 mm/rmap.c:1789
 __munlock_isolated_page+0x89/0x1a0 mm/mlock.c:138
 __munlock_pagevec+0x392/0x7a0 mm/mlock.c:346
 munlock_vma_pages_range+0x5cc/0x790 mm/mlock.c:499
 munlock_vma_pages_all mm/internal.h:306 [inline]
 exit_mmap+0x24f/0x300 mm/mmap.c:3124
 __mmput kernel/fork.c:1082 [inline]
 mmput+0xea/0x280 kernel/fork.c:1103
 exit_mm kernel/exit.c:485 [inline]
 do_exit+0x4ac/0x18c0 kernel/exit.c:784
 do_group_exit+0xb4/0x1c0 kernel/exit.c:895
 get_signal+0x2a2/0x1320 kernel/signal.c:2734
 do_signal+0x2f/0x6c0 arch/x86/kernel/signal.c:815
 exit_to_usermode_loop+0x250/0x2c0 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:278 [inline]
 do_syscall_64+0x384/0x3a0 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 18724 Comm: syz-executor.5 Not tainted 5.5.0-rc1-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 2019/12/31 21:42 https://github.com/google/ktsan.git kcsan 245a43005292 25a0186e .config log report