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KCSAN: data-race in __dentry_kill / lookup_fast (13)

Status: moderation: reported on 2025/02/24 20:41
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+d39da0f4ddf3340ad108@syzkaller.appspotmail.com
First crash: 3d01h, last: 3d01h
▶ ▼ Similar bugs (12)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __dentry_kill / lookup_fast (5) fs 12 1368d 1440d 0/28 auto-closed as invalid on 2021/07/05 09:49
upstream KCSAN: data-race in __dentry_kill / lookup_fast (8) fs 8 679d 743d 0/28 auto-obsoleted due to no activity on 2023/05/25 00:07
upstream KCSAN: data-race in __dentry_kill / lookup_fast (2) fs 5 1649d 1709d 0/28 auto-closed as invalid on 2020/09/27 09:27
upstream KCSAN: data-race in __dentry_kill / lookup_fast fs 10 1732d 1825d 0/28 closed as invalid on 2020/06/18 14:24
upstream KCSAN: data-race in __dentry_kill / lookup_fast (11) fs 1 223d 223d 0/28 auto-obsoleted due to no activity on 2024/08/23 20:28
upstream KCSAN: data-race in __dentry_kill / lookup_fast (10) fs 3 333d 371d 0/28 auto-obsoleted due to no activity on 2024/05/05 12:07
upstream KCSAN: data-race in __dentry_kill / lookup_fast (12) fs 3 59d 112d 0/28 auto-obsoleted due to no activity on 2025/02/24 08:27
upstream KCSAN: data-race in __dentry_kill / lookup_fast (7) fs 27 790d 1050d 0/28 auto-obsoleted due to no activity on 2023/02/12 11:35
upstream KCSAN: data-race in __dentry_kill / lookup_fast (6) fs 1 1195d 1195d 0/28 auto-closed as invalid on 2021/12/25 02:52
upstream KCSAN: data-race in __dentry_kill / lookup_fast (4) fs 3 1489d 1514d 0/28 auto-closed as invalid on 2021/03/06 20:57
upstream KCSAN: data-race in __dentry_kill / lookup_fast (3) fs 3 1551d 1543d 0/28 auto-closed as invalid on 2021/01/03 16:37
upstream KCSAN: data-race in __dentry_kill / lookup_fast (9) fs 31 411d 446d 0/28 auto-obsoleted due to no activity on 2024/02/17 10:11

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

read-write to 0xffff88811d0f9180 of 4 bytes by task 7347 on cpu 0:
 dentry_unlist fs/dcache.c:588 [inline]
 __dentry_kill+0x22e/0x4c0 fs/dcache.c:657
 dput+0x5c/0xd0 fs/dcache.c:885
 __fput+0x428/0x640 fs/file_table.c:472
 __fput_sync+0x96/0xc0 fs/file_table.c:550
 __do_sys_close fs/open.c:1580 [inline]
 __se_sys_close fs/open.c:1565 [inline]
 __x64_sys_close+0x55/0xe0 fs/open.c:1565
 x64_sys_call+0x266c/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:4
 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 0xffff88811d0f9180 of 4 bytes by task 7726 on cpu 1:
 d_revalidate fs/namei.c:927 [inline]
 lookup_fast+0xe9/0x320 fs/namei.c:1741
 lookup_fast_for_open fs/namei.c:3688 [inline]
 open_last_lookups fs/namei.c:3721 [inline]
 path_openat+0x41e/0x1fc0 fs/namei.c:3986
 do_filp_open+0x107/0x230 fs/namei.c:4016
 do_sys_openat2+0xab/0x120 fs/open.c:1428
 do_sys_open fs/open.c:1443 [inline]
 __do_sys_openat fs/open.c:1459 [inline]
 __se_sys_openat fs/open.c:1454 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1454
 x64_sys_call+0x2b30/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:258
 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: 0x00400008 -> 0x00008008

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 7726 Comm: syz-executor Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================
==================================================================
BUG: KCSAN: data-race in __dentry_kill / step_into

read-write to 0xffff88811d1e9180 of 4 bytes by task 7347 on cpu 0:
 dentry_unlist fs/dcache.c:588 [inline]
 __dentry_kill+0x22e/0x4c0 fs/dcache.c:657
 dput+0x5c/0xd0 fs/dcache.c:885
 __fput+0x428/0x640 fs/file_table.c:472
 __fput_sync+0x96/0xc0 fs/file_table.c:550
 __do_sys_close fs/open.c:1580 [inline]
 __se_sys_close fs/open.c:1565 [inline]
 __x64_sys_close+0x55/0xe0 fs/open.c:1565
 x64_sys_call+0x266c/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:4
 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 0xffff88811d1e9180 of 4 bytes by task 7726 on cpu 1:
 __d_entry_type include/linux/dcache.h:416 [inline]
 d_is_symlink include/linux/dcache.h:446 [inline]
 step_into+0x129/0x820 fs/namei.c:1957
 open_last_lookups fs/namei.c:3777 [inline]
 path_openat+0x13e5/0x1fc0 fs/namei.c:3986
 do_filp_open+0x107/0x230 fs/namei.c:4016
 do_sys_openat2+0xab/0x120 fs/open.c:1428
 do_sys_open fs/open.c:1443 [inline]
 __do_sys_openat fs/open.c:1459 [inline]
 __se_sys_openat fs/open.c:1454 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1454
 x64_sys_call+0x2b30/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:258
 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: 0x00400008 -> 0x00008008

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 7726 Comm: syz-executor Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================
==================================================================
BUG: KCSAN: data-race in __dentry_kill / lookup_fast

read-write to 0xffff88810673ad80 of 4 bytes by task 7347 on cpu 0:
 dentry_unlist fs/dcache.c:588 [inline]
 __dentry_kill+0x22e/0x4c0 fs/dcache.c:657
 dput+0x5c/0xd0 fs/dcache.c:885
 __fput+0x428/0x640 fs/file_table.c:472
 __fput_sync+0x96/0xc0 fs/file_table.c:550
 __do_sys_close fs/open.c:1580 [inline]
 __se_sys_close fs/open.c:1565 [inline]
 __x64_sys_close+0x55/0xe0 fs/open.c:1565
 x64_sys_call+0x266c/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:4
 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 0xffff88810673ad80 of 4 bytes by task 7726 on cpu 1:
 d_revalidate fs/namei.c:927 [inline]
 lookup_fast+0xe9/0x320 fs/namei.c:1741
 lookup_fast_for_open fs/namei.c:3688 [inline]
 open_last_lookups fs/namei.c:3721 [inline]
 path_openat+0x41e/0x1fc0 fs/namei.c:3986
 do_filp_open+0x107/0x230 fs/namei.c:4016
 do_sys_openat2+0xab/0x120 fs/open.c:1428
 do_sys_open fs/open.c:1443 [inline]
 __do_sys_openat fs/open.c:1459 [inline]
 __se_sys_openat fs/open.c:1454 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1454
 x64_sys_call+0x2b30/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:258
 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: 0x00400008 -> 0x00008008

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 7726 Comm: syz-executor Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================
==================================================================
BUG: KCSAN: data-race in __dentry_kill / lookup_fast

read-write to 0xffff88810043d0c0 of 4 bytes by task 7347 on cpu 0:
 dentry_unlist fs/dcache.c:588 [inline]
 __dentry_kill+0x22e/0x4c0 fs/dcache.c:657
 dput+0x5c/0xd0 fs/dcache.c:885
 __fput+0x428/0x640 fs/file_table.c:472
 __fput_sync+0x96/0xc0 fs/file_table.c:550
 __do_sys_close fs/open.c:1580 [inline]
 __se_sys_close fs/open.c:1565 [inline]
 __x64_sys_close+0x55/0xe0 fs/open.c:1565
 x64_sys_call+0x266c/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:4
 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 0xffff88810043d0c0 of 4 bytes by task 7726 on cpu 1:
 d_revalidate fs/namei.c:927 [inline]
 lookup_fast+0xe9/0x320 fs/namei.c:1741
 lookup_fast_for_open fs/namei.c:3688 [inline]
 open_last_lookups fs/namei.c:3721 [inline]
 path_openat+0x41e/0x1fc0 fs/namei.c:3986
 do_filp_open+0x107/0x230 fs/namei.c:4016
 do_sys_openat2+0xab/0x120 fs/open.c:1428
 do_sys_open fs/open.c:1443 [inline]
 __do_sys_openat fs/open.c:1459 [inline]
 __se_sys_openat fs/open.c:1454 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1454
 x64_sys_call+0x2b30/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:258
 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: 0x00400008 -> 0x00008008

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 7726 Comm: syz-executor Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================
==================================================================
BUG: KCSAN: data-race in __dentry_kill / step_into

read-write to 0xffff888106736180 of 4 bytes by task 7347 on cpu 0:
 dentry_unlist fs/dcache.c:588 [inline]
 __dentry_kill+0x22e/0x4c0 fs/dcache.c:657
 dput+0x5c/0xd0 fs/dcache.c:885
 __fput+0x428/0x640 fs/file_table.c:472
 __fput_sync+0x96/0xc0 fs/file_table.c:550
 __do_sys_close fs/open.c:1580 [inline]
 __se_sys_close fs/open.c:1565 [inline]
 __x64_sys_close+0x55/0xe0 fs/open.c:1565
 x64_sys_call+0x266c/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:4
 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 0xffff888106736180 of 4 bytes by task 7726 on cpu 1:
 __d_entry_type include/linux/dcache.h:416 [inline]
 d_is_symlink include/linux/dcache.h:446 [inline]
 step_into+0x129/0x820 fs/namei.c:1957
 open_last_lookups fs/namei.c:3777 [inline]
 path_openat+0x13e5/0x1fc0 fs/namei.c:3986
 do_filp_open+0x107/0x230 fs/namei.c:4016
 do_sys_openat2+0xab/0x120 fs/open.c:1428
 do_sys_open fs/open.c:1443 [inline]
 __do_sys_openat fs/open.c:1459 [inline]
 __se_sys_openat fs/open.c:1454 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1454
 x64_sys_call+0x2b30/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:258
 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: 0x00400008 -> 0x00008008

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 7726 Comm: syz-executor Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/24 20:41 upstream d082ecbc71e9 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __dentry_kill / lookup_fast
* Struck through repros no longer work on HEAD.