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KCSAN: data-race in d_alloc_parallel / d_set_d_op (10)

Status: auto-obsoleted due to no activity on 2024/12/22 11:11
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+2c167a88c95ba9499bdb@syzkaller.appspotmail.com
First crash: 346d, last: 324d
▶ ▼ 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 1688d 1688d 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 1985d 2148d 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 388d 592d 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 1181d 1237d 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 1848d 1848d 0/29 auto-closed as invalid on 2020/09/29 03:57
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (8) fs 6 43 630d 647d 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 150d 203d 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 1274d 1320d 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 1751d 1744d 0/29 auto-closed as invalid on 2021/01/03 18:19
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (11) fs 6 1 264d 264d 0/29 auto-obsoleted due to no activity on 2025/02/20 09:31
upstream KCSAN: data-race in d_alloc_parallel / d_set_d_op (5) fs 6 13 1558d 1647d 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 0xffff8881065ddb40 of 4 bytes by task 29117 on cpu 0:
 d_set_d_op+0xfb/0x1f0 fs/dcache.c:1804
 proc_pident_instantiate+0x164/0x180 fs/proc/base.c:2709
 proc_pident_lookup+0x112/0x190 fs/proc/base.c:2732
 proc_tgid_base_lookup+0x2b/0x40 fs/proc/base.c:3444
 __lookup_slow+0x184/0x250 fs/namei.c:1732
 lookup_slow+0x3c/0x60 fs/namei.c:1749
 walk_component fs/namei.c:2053 [inline]
 link_path_walk+0x69e/0x820 fs/namei.c:2418
 path_openat+0x1af/0x1fa0 fs/namei.c:3929
 do_filp_open+0xf7/0x200 fs/namei.c:3960
 do_sys_openat2+0xab/0x120 fs/open.c:1415
 do_sys_open fs/open.c:1430 [inline]
 __do_sys_openat fs/open.c:1446 [inline]
 __se_sys_openat fs/open.c:1441 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1441
 x64_sys_call+0x1025/0x2d60 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 0xffff8881065ddb40 of 4 bytes by task 29116 on cpu 1:
 d_in_lookup include/linux/dcache.h:378 [inline]
 d_wait_lookup fs/dcache.c:2459 [inline]
 d_alloc_parallel+0x60b/0xc80 fs/dcache.c:2547
 __lookup_slow+0x8d/0x250 fs/namei.c:1717
 lookup_slow+0x3c/0x60 fs/namei.c:1749
 walk_component fs/namei.c:2053 [inline]
 link_path_walk+0x69e/0x820 fs/namei.c:2418
 path_openat+0x1af/0x1fa0 fs/namei.c:3929
 do_filp_open+0xf7/0x200 fs/namei.c:3960
 do_sys_openat2+0xab/0x120 fs/open.c:1415
 do_sys_open fs/open.c:1430 [inline]
 __do_sys_openat fs/open.c:1446 [inline]
 __se_sys_openat fs/open.c:1441 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1441
 x64_sys_call+0x1025/0x2d60 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: 29116 Comm: syz.6.6699 Tainted: G        W          6.12.0-rc4-syzkaller-00261-g850925a8133c #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/27 11:10 upstream 850925a8133c 65e8686b .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
2024/10/05 03:32 upstream 2f91ff27b0ee d7906eff .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.