syzbot


KCSAN: data-race in __dentry_kill / fast_dput (2)

Status: moderation: reported on 2024/06/01 04:43
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+dfcb311253a541a4ee29@syzkaller.appspotmail.com
First crash: 131d, last: 8d09h
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __dentry_kill / fast_dput fs 9 179d 262d 0/28 auto-obsoleted due to no activity on 2024/05/18 12:55

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

write to 0xffff888106971a90 of 8 bytes by task 6606 on cpu 0:
 __d_drop fs/dcache.c:521 [inline]
 __dentry_kill+0x13e/0x4c0 fs/dcache.c:613
 dput+0x5c/0xd0 fs/dcache.c:857
 handle_mounts fs/namei.c:1579 [inline]
 step_into+0x21a/0x810 fs/namei.c:1891
 walk_component+0x169/0x230 fs/namei.c:2059
 lookup_last fs/namei.c:2556 [inline]
 path_lookupat+0x10a/0x2b0 fs/namei.c:2580
 filename_lookup+0x127/0x300 fs/namei.c:2609
 user_path_at+0x3c/0x110 fs/namei.c:3016
 do_mount fs/namespace.c:3844 [inline]
 __do_sys_mount fs/namespace.c:4055 [inline]
 __se_sys_mount+0x248/0x2d0 fs/namespace.c:4032
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4032
 x64_sys_call+0x203e/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888106971a90 of 8 bytes by task 6605 on cpu 1:
 hlist_bl_unhashed include/linux/list_bl.h:54 [inline]
 d_unhashed include/linux/dcache.h:354 [inline]
 retain_dentry fs/dcache.c:698 [inline]
 fast_dput+0x65/0x2c0 fs/dcache.c:794
 dput+0x24/0xd0 fs/dcache.c:851
 handle_mounts fs/namei.c:1579 [inline]
 step_into+0x21a/0x810 fs/namei.c:1891
 walk_component+0x169/0x230 fs/namei.c:2059
 lookup_last fs/namei.c:2556 [inline]
 path_lookupat+0x10a/0x2b0 fs/namei.c:2580
 filename_lookup+0x127/0x300 fs/namei.c:2609
 user_path_at+0x3c/0x110 fs/namei.c:3016
 do_mount fs/namespace.c:3844 [inline]
 __do_sys_mount fs/namespace.c:4055 [inline]
 __se_sys_mount+0x248/0x2d0 fs/namespace.c:4032
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4032
 x64_sys_call+0x203e/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff8882377cd520 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 6605 Comm: syz.0.1054 Tainted: G        W          6.12.0-rc1-syzkaller-00031-ge32cde8d2bd7 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================

Crashes (21):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/02 00:03 upstream e32cde8d2bd7 ea2b66a6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/09/06 06:20 upstream ad618736883b 464ac2ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/09/02 11:54 upstream c9f016e72b5c 1eda0d14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/09/01 18:39 upstream 431c1646e1f8 1eda0d14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/08/28 14:49 upstream 86987d84b968 ef3de9e8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/08/24 08:50 upstream 60f0560f53e3 d7d32352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/08/22 13:00 upstream 872cf28b8df9 ca02180f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/08/21 18:06 upstream b311c1b497e5 db5852f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/08/15 09:34 upstream d07b43284ab3 e4bacdaf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/08/13 10:43 upstream d74da846046a 7b0f4b46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/08/12 22:20 upstream 7c626ce4bae1 842184b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/08/06 10:21 upstream b446a2dae984 e1bdb00a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/08/04 00:43 upstream 17712b7ea075 1786a2a8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/07/16 21:33 upstream d67978318827 b66b37bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/07/10 08:52 upstream 34afb82a3c67 bc144f9a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/07/08 04:59 upstream 256abd8e550c 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/07/06 08:57 upstream d270dd21bee0 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/06/10 22:59 upstream 83a7eefedc9b 048c640a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/06/09 10:51 upstream 061d1af7b030 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/06/07 17:46 upstream 8a92980606e3 121701b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
2024/06/01 04:43 upstream d8ec19857b09 3113787f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / fast_dput
* Struck through repros no longer work on HEAD.