syzbot


KCSAN: data-race in delete_from_page_cache_batch / migrate_pages (3)

Status: auto-closed as invalid on 2022/03/22 17:18
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 290d, last: 290d
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in delete_from_page_cache_batch / migrate_pages 2 594d 595d 0/24 auto-closed as invalid on 2021/05/22 08:02
upstream KCSAN: data-race in delete_from_page_cache_batch / migrate_pages (2) 1 489d 489d 0/24 auto-closed as invalid on 2021/09/04 09:15

Sample crash report:
==================================================================
BUG: KCSAN: data-race in delete_from_page_cache_batch / migrate_pages

write to 0xffffea0005c763d8 of 8 bytes by task 9673 on cpu 1:
 page_cache_delete_batch mm/filemap.c:304 [inline]
 delete_from_page_cache_batch+0x301/0x760 mm/filemap.c:330
 truncate_inode_pages_range+0x305/0x8b0 mm/truncate.c:379
 truncate_inode_pages+0x20/0x30 mm/truncate.c:461
 swap_inode_boot_loader fs/ext4/ioctl.c:406 [inline]
 __ext4_ioctl fs/ext4/ioctl.c:1351 [inline]
 ext4_ioctl+0x1a0e/0x1f40 fs/ext4/ioctl.c:1578
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffea0005c763d8 of 8 bytes by task 9682 on cpu 0:
 __PageMovable include/linux/page-flags.h:592 [inline]
 __unmap_and_move mm/migrate.c:933 [inline]
 unmap_and_move mm/migrate.c:1105 [inline]
 migrate_pages+0x47e/0x1810 mm/migrate.c:1388
 do_mbind+0x5b7/0x760 mm/mempolicy.c:1334
 kernel_mbind mm/mempolicy.c:1481 [inline]
 __do_sys_mbind mm/mempolicy.c:1559 [inline]
 __se_sys_mbind+0x151/0x410 mm/mempolicy.c:1555
 __x64_sys_mbind+0x74/0x80 mm/mempolicy.c:1555
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffff888136d2dc20 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9682 Comm: syz-executor.3 Not tainted 5.17.0-rc4-syzkaller-00002-gd567f5db412e-dirty #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 2022/02/15 17:11 upstream d567f5db412e 8b9ca619 .config log report info KCSAN: data-race in delete_from_page_cache_batch / migrate_pages
* Struck through repros no longer work on HEAD.