syzbot


KCSAN: data-race in list_lru_add / list_lru_count_node

Status: auto-closed as invalid on 2020/06/18 13:43
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 857d, last: 857d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in list_lru_add / list_lru_count_node (3) 3 569d 595d 0/23 auto-closed as invalid on 2021/02/28 22:07
upstream KCSAN: data-race in list_lru_add / list_lru_count_node (6) 15 209d 343d 0/23 auto-closed as invalid on 2022/02/23 08:49
upstream KCSAN: data-race in list_lru_add / list_lru_count_node (2) 1 787d 787d 0/23 auto-closed as invalid on 2020/07/25 12:43
upstream KCSAN: data-race in list_lru_add / list_lru_count_node (4) 5 457d 469d 0/23 auto-closed as invalid on 2021/06/20 16:41
upstream KCSAN: data-race in list_lru_add / list_lru_count_node (5) 3 388d 409d 0/23 auto-closed as invalid on 2021/09/03 02:37

Sample crash report:
==================================================================
BUG: KCSAN: data-race in list_lru_add / list_lru_count_node

write to 0xffff88812a5e69a8 of 8 bytes by task 30270 on cpu 0:
 list_lru_add+0x256/0x460 mm/list_lru.c:140
 d_lru_add+0xa9/0xf0 fs/dcache.c:404
 retain_dentry fs/dcache.c:653 [inline]
 dput+0x3f4/0x700 fs/dcache.c:854
 path_put_conditional fs/namei.c:863 [inline]
 follow_managed+0x205/0x720 fs/namei.c:1359
 walk_component+0x525/0x9a0 fs/namei.c:1921
 lookup_last fs/namei.c:2391 [inline]
 path_lookupat.isra.0+0x129/0x2e0 fs/namei.c:2436
 filename_lookup+0x145/0x2b0 fs/namei.c:2466
 user_path_at_empty+0x47/0x60 fs/namei.c:2746
 user_path_at include/linux/namei.h:58 [inline]
 do_faccessat+0x12b/0x470 fs/open.c:398
 __do_sys_access fs/open.c:450 [inline]
 __se_sys_access fs/open.c:448 [inline]
 __x64_sys_access+0x3c/0x50 fs/open.c:448
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88812a5e69a8 of 8 bytes by task 30268 on cpu 1:
 list_lru_count_node+0x32/0x50 mm/list_lru.c:205
 list_lru_count include/linux/list_lru.h:132 [inline]
 shrink_dcache_sb+0x143/0x1c0 fs/dcache.c:1243
 reconfigure_super+0x318/0x570 fs/super.c:940
 do_remount fs/namespace.c:2553 [inline]
 do_mount+0x1120/0x14d0 fs/namespace.c:3098
 __do_sys_mount fs/namespace.c:3316 [inline]
 __se_sys_mount fs/namespace.c:3293 [inline]
 __x64_sys_mount+0x12b/0x1a0 fs/namespace.c:3293
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 30268 Comm: syz-executor.2 Not tainted 5.6.0-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 2020/04/11 01:12 https://github.com/google/ktsan.git kcsan 40959e34d670 a8c6a3f8 .config log report