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KCSAN: data-race in dput / shrink_dentry_list

Status: auto-closed as invalid on 2021/01/12 13:00
Subsystems: fs
[Documentation on labels]
First crash: 1233d, last: 1233d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in dput / shrink_dentry_list (2) fs 1 1189d 1189d 0/26 auto-closed as invalid on 2021/02/25 05:57
upstream KCSAN: data-race in dput / shrink_dentry_list (4) fs 1 574d 574d 0/26 auto-obsoleted due to no activity on 2022/11/02 13:46
upstream KCSAN: data-race in dput / shrink_dentry_list (3) fs 5 832d 876d 0/26 auto-closed as invalid on 2022/02/16 22:40

Sample crash report:
==================================================================
BUG: KCSAN: data-race in dput / shrink_dentry_list

read-write to 0xffff888107a6c0c0 of 4 bytes by task 6229 on cpu 1:
 d_shrink_del fs/dcache.c:421 [inline]
 shrink_dentry_list+0x20f/0x590 fs/dcache.c:1128
 shrink_dcache_sb+0x10d/0x1c0 fs/dcache.c:1261
 reconfigure_super+0x267/0x4d0 fs/super.c:940
 do_remount fs/namespace.c:2612 [inline]
 path_mount+0x13b1/0x1c10 fs/namespace.c:3197
 do_mount fs/namespace.c:3218 [inline]
 __do_sys_mount fs/namespace.c:3426 [inline]
 __se_sys_mount+0x23d/0x2e0 fs/namespace.c:3403
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3403
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888107a6c0c0 of 4 bytes by task 10456 on cpu 0:
 fast_dput fs/dcache.c:746 [inline]
 dput+0x2f/0x420 fs/dcache.c:865
 path_put fs/namei.c:496 [inline]
 do_unlinkat+0x37a/0x4d0 fs/namei.c:3912
 __do_sys_unlink fs/namei.c:3943 [inline]
 __se_sys_unlink fs/namei.c:3941 [inline]
 __x64_sys_unlink+0x2c/0x30 fs/namei.c:3941
 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: 10456 Comm: syz-executor.1 Not tainted 5.10.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/12/08 12:59 upstream cd796ed33450 9af51e31 .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.