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KCSAN: data-race in d_alloc_parallel / d_set_d_op (11)

Status: auto-obsoleted due to no activity on 2025/02/20 09:31
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+c14e4eb7c49e37e24c7a@syzkaller.appspotmail.com
First crash: 221d, last: 221d
▶ ▼ Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (4) fs 6 1 1645d 1645d 0/29 auto-closed as invalid on 2021/03/08 01:09
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op fs 6 23 1942d 2106d 0/29 auto-closed as invalid on 2020/06/18 13:33
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (9) fs 6 29 345d 550d 0/29 auto-obsoleted due to no activity on 2024/09/27 23:53
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (7) fs 6 4 1138d 1194d 0/29 auto-closed as invalid on 2022/07/28 05:03
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (2) fs 6 1 1805d 1805d 0/29 auto-closed as invalid on 2020/09/29 03:57
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (10) fs 6 2 281d 303d 0/29 auto-obsoleted due to no activity on 2024/12/22 11:11
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (8) fs 6 43 587d 604d 0/29 auto-obsoleted due to no activity on 2024/01/30 06:40
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (12) fs 6 2 108d 161d 0/29 auto-obsoleted due to no activity on 2025/06/13 19:10
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (6) fs 6 3 1231d 1277d 0/29 auto-closed as invalid on 2022/04/26 06:41
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (3) fs 6 2 1709d 1701d 0/29 auto-closed as invalid on 2021/01/03 18:19
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (5) fs 6 13 1515d 1604d 0/29 auto-closed as invalid on 2021/07/16 11:19

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

read-write to 0xffff88810636c480 of 4 bytes by task 24401 on cpu 0:
 d_set_d_op+0xfb/0x1f0 fs/dcache.c:1814
 proc_pident_instantiate+0x164/0x180 fs/proc/base.c:2710
 proc_pident_lookup+0x112/0x190 fs/proc/base.c:2733
 proc_tgid_base_lookup+0x2b/0x40 fs/proc/base.c:3445
 __lookup_slow+0x184/0x250 fs/namei.c:1791
 lookup_slow+0x3c/0x60 fs/namei.c:1808
 walk_component fs/namei.c:2112 [inline]
 link_path_walk+0x69e/0x820 fs/namei.c:2477
 path_openat+0x1af/0x1fa0 fs/namei.c:3983
 do_filp_open+0x107/0x230 fs/namei.c:4014
 do_sys_openat2+0xab/0x120 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_openat fs/open.c:1433 [inline]
 __se_sys_openat fs/open.c:1428 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1428
 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

read to 0xffff88810636c480 of 4 bytes by task 24402 on cpu 1:
 d_in_lookup include/linux/dcache.h:378 [inline]
 d_wait_lookup fs/dcache.c:2471 [inline]
 d_alloc_parallel+0x5fe/0xc60 fs/dcache.c:2559
 __lookup_slow+0x8d/0x250 fs/namei.c:1776
 lookup_slow+0x3c/0x60 fs/namei.c:1808
 walk_component fs/namei.c:2112 [inline]
 link_path_walk+0x69e/0x820 fs/namei.c:2477
 path_openat+0x1af/0x1fa0 fs/namei.c:3983
 do_filp_open+0x107/0x230 fs/namei.c:4014
 do_sys_openat2+0xab/0x120 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_openat fs/open.c:1433 [inline]
 __se_sys_openat fs/open.c:1428 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1428
 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: 0x10000000 -> 0x1000000c

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 24402 Comm: syz.6.5429 Tainted: G        W          6.13.0-rc4-syzkaller-00012-g9b2ffa6148b1 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/26 09:30 upstream 9b2ffa6148b1 444551c4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in d_alloc_parallel / d_set_d_op
* Struck through repros no longer work on HEAD.