syzbot


KCSAN: data-race in __dentry_kill / d_set_d_op (16)

Status: auto-obsoleted due to no activity on 2024/02/04 06:56
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+bb35d724c36857653564@syzkaller.appspotmail.com
First crash: 118d, last: 54d
Similar bugs (15)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (9) fs 1 748d 748d 0/26 auto-closed as invalid on 2022/03/12 00:21
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (7) fs 2 984d 1017d 0/26 auto-closed as invalid on 2021/07/19 11:09
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (3) fs 6 1356d 1396d 0/26 closed as invalid on 2020/06/18 14:24
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (2) fs 9 1486d 1555d 0/26 auto-closed as invalid on 2020/04/08 20:57
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (5) fs 1 1205d 1173d 0/26 auto-closed as invalid on 2020/12/21 11:58
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (10) fs 5 648d 710d 0/26 auto-closed as invalid on 2022/06/20 15:46
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (15) fs 13 157d 217d 0/26 auto-obsoleted due to no activity on 2023/10/24 14:04
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (14) fs 1 252d 252d 0/26 auto-obsoleted due to no activity on 2023/07/21 00:16
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (4) fs 3 1285d 1304d 0/26 auto-closed as invalid on 2020/09/21 06:01
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (11) fs 1 608d 608d 0/26 auto-closed as invalid on 2022/07/30 10:14
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (6) fs 1 1076d 1076d 0/26 auto-closed as invalid on 2021/04/18 21:16
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (12) fs 3 513d 558d 0/26 auto-obsoleted due to no activity on 2022/11/02 16:09
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (8) fs 13 787d 944d 0/26 auto-closed as invalid on 2022/02/01 06:29
upstream KCSAN: data-race in __dentry_kill / d_set_d_op fs 3 1566d 1573d 0/26 closed as invalid on 2019/11/19 14:14
upstream KCSAN: data-race in __dentry_kill / d_set_d_op (13) fs 4 364d 423d 0/26 auto-obsoleted due to no activity on 2023/04/04 19:35

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __dentry_kill / d_set_d_op

read-write to 0xffff88812b2add80 of 4 bytes by task 3376 on cpu 0:
 d_set_d_op+0x150/0x1e0 fs/dcache.c:1935
 simple_lookup+0x7c/0xa0 fs/libfs.c:78
 __lookup_slow+0x17a/0x230 fs/namei.c:1694
 lookup_slow+0x3c/0x60 fs/namei.c:1711
 walk_component+0x1ec/0x230 fs/namei.c:2002
 lookup_last fs/namei.c:2459 [inline]
 path_lookupat+0x10a/0x2a0 fs/namei.c:2483
 filename_lookup+0x126/0x300 fs/namei.c:2512
 user_path_at_empty+0x42/0x110 fs/namei.c:2911
 user_path_at include/linux/namei.h:57 [inline]
 inotify_find_inode fs/notify/inotify/inotify_user.c:378 [inline]
 __do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:777 [inline]
 __se_sys_inotify_add_watch+0x119/0x820 fs/notify/inotify/inotify_user.c:730
 __x64_sys_inotify_add_watch+0x43/0x50 fs/notify/inotify/inotify_user.c:730
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff88812b2add80 of 4 bytes by task 3465 on cpu 1:
 dentry_unlist fs/dcache.c:572 [inline]
 __dentry_kill+0x237/0x4a0 fs/dcache.c:603
 dentry_kill+0x8d/0x1e0
 dput+0x118/0x1f0 fs/dcache.c:913
 handle_mounts fs/namei.c:1555 [inline]
 step_into+0x21a/0x800 fs/namei.c:1840
 walk_component+0x164/0x230 fs/namei.c:2008
 lookup_last fs/namei.c:2459 [inline]
 path_lookupat+0x10a/0x2a0 fs/namei.c:2483
 filename_lookup+0x126/0x300 fs/namei.c:2512
 user_path_at_empty+0x42/0x110 fs/namei.c:2911
 user_path_at include/linux/namei.h:57 [inline]
 inotify_find_inode fs/notify/inotify/inotify_user.c:378 [inline]
 __do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:777 [inline]
 __se_sys_inotify_add_watch+0x119/0x820 fs/notify/inotify/inotify_user.c:730
 __x64_sys_inotify_add_watch+0x43/0x50 fs/notify/inotify/inotify_user.c:730
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x10000000 -> 0x00000008

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3465 Comm: udevd Not tainted 6.7.0-rc7-syzkaller-00049-g453f5db0619e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
==================================================================

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/12/31 06:55 upstream 453f5db0619e fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / d_set_d_op
2023/12/29 02:05 upstream 505e701c0b2c fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / d_set_d_op
2023/12/25 11:29 upstream 861deac3b092 fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / d_set_d_op
2023/11/23 05:47 upstream 9b6de136b5f0 fc59b78e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / d_set_d_op
2023/11/17 16:13 upstream 6bc40e44f1dd cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / d_set_d_op
2023/10/28 13:39 upstream 56567a20b22b 3c418d72 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / d_set_d_op
* Struck through repros no longer work on HEAD.