KCSAN: data-race in alloc_pid / copy_process (2)

Status: moderation: reported on 2020/06/09 14:58
Subsystems: kernel
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+0718f65353d72efaac1e@syzkaller.appspotmail.com
First crash: 2439d, last: 18h38m
✨ AI Jobs (4)
ID Workflow Result Correct Bug Created Started Finished Revision Error
f5f3590f assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ KCSAN: data-race in alloc_pid / copy_process (2) 2026/05/16 15:14 2026/05/16 15:40 2026/05/16 16:05 de5aae85

			
		
f1fb5761 repro KCSAN: data-race in alloc_pid / copy_process (2) 2026/03/07 22:22 2026/03/07 22:22 2026/03/07 22:24 31e9c887

			
		
321d819b assessment-kcsan Benign: ✅ Confident: ✅ KCSAN: data-race in alloc_pid / copy_process (2) 2026/02/24 21:06 2026/02/24 21:06 2026/02/24 21:08 305c0ec5

			
		
3400e0bb assessment-kcsan 💥 KCSAN: data-race in alloc_pid / copy_process (2) 2026/01/10 03:12 2026/01/10 03:12 2026/01/10 03:13 75199160
Error 429, Message: You exceeded your current quota, please check your plan and billing details. For more information on this error, head to: https://ai.google.dev/gemini-api/docs/rate-limits. To moni...
truncated to first 200 bytes; open job for full error
Discussions (2)
Title Replies (including bot) Last reply
[PATCH v2] pid: annotate data-races around pid_ns->pid_allocated 4 (4) 2025/04/28 08:30
[PATCH v1] pid: annotate data-races around pid_ns->pid_allocated 7 (7) 2025/04/25 05:37
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in alloc_pid / copy_process kernel 6 5 2457d 2467d 0/29 closed as invalid on 2019/11/19 13:24

Sample crash report:
==================================================================
BUG: KCSAN: data-race in alloc_pid / copy_process

read-write to 0xffffffff86c5c268 of 4 bytes by task 5451 on cpu 1:
 alloc_pid+0x6bb/0x930 kernel/pid.c:332
 copy_process+0x11aa/0x2310 kernel/fork.c:2305
 kernel_clone+0x1c0/0x5f0 kernel/fork.c:2748
 __do_sys_clone kernel/fork.c:2889 [inline]
 __se_sys_clone kernel/fork.c:2873 [inline]
 __x64_sys_clone+0x143/0x180 kernel/fork.c:2873
 x64_sys_call+0x1222/0x3020 arch/x86/include/generated/asm/syscalls_64.h:57
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff86c5c268 of 4 bytes by task 6194 on cpu 0:
 copy_process+0x1aae/0x2310 kernel/fork.c:2468
 kernel_clone+0x1c0/0x5f0 kernel/fork.c:2748
 __do_sys_clone kernel/fork.c:2889 [inline]
 __se_sys_clone kernel/fork.c:2873 [inline]
 __x64_sys_clone+0x143/0x180 kernel/fork.c:2873
 x64_sys_call+0x1222/0x3020 arch/x86/include/generated/asm/syscalls_64.h:57
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x8000012d -> 0x8000012e

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6194 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
==================================================================

Crashes (3557):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/25 06:35 upstream e2a936998ab2 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/25 01:40 upstream 48a5a7ab8d6a 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/24 21:55 upstream 48a5a7ab8d6a dd737a83 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/23 05:44 upstream 4539944e5151 881ce5c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/22 21:39 upstream 4539944e5151 4a865b71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/21 22:49 upstream 248951ddc14d b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/18 22:46 upstream 1229e2e57a5c 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/18 13:12 upstream 94515f3a7d42 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/17 03:19 upstream fce2dfa773ce 7f27c57a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/16 23:24 upstream 37e2f878a7a6 71b49442 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/16 01:03 upstream 58717b2a1365 27a8bd60 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/15 11:08 upstream 58717b2a1365 a4ed0f4f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/15 07:11 upstream 3b029c035b34 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/12 18:24 upstream 44696aa3a489 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/10 02:13 upstream a635d6748234 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/09 16:27 upstream 2c7c88a412aa a0c310a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/08 23:51 upstream 0e35b9b6ec0f b9f1ceaa .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/08 17:14 upstream 0e35b9b6ec0f 88a4b44c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/06 23:10 upstream 8cdeaa50eae8 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/06 04:24 upstream f105f3631d51 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/04 16:07 upstream 1e9cdc2ea15a fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/07/04 06:19 upstream 71dfdfb0209b fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/30 05:14 upstream dc59e4fea9d8 fff8d0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/29 11:12 upstream dc59e4fea9d8 6a0c72dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/27 23:58 upstream 780d569e6c4b fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/27 06:49 upstream 5a66900afbd6 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/27 00:14 upstream 51cb1aa1250c fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/26 16:59 upstream 4edcdefd4083 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/26 01:22 upstream a142da0b2d32 7ff32d8b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/22 16:18 upstream ef0c9f75a195 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/22 05:38 upstream 8cd8cf7a07e5 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/21 11:00 upstream 390d73adf896 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/20 19:25 upstream 1a3746ccbb0a 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/20 05:26 upstream 5e2e14749c3d 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/19 03:25 upstream 83f1454877cc a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/15 14:25 upstream 0e0611827f33 50bb0618 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/14 15:33 upstream 8cd9520d35a6 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/14 02:19 upstream 2b07ea76fd28 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/13 07:20 upstream 062871f1371b 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/12 13:44 upstream 2b414a95b8f7 e93da63e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/10 13:38 upstream acb7500801e9 f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/10 07:10 upstream 685441a6d3f1 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/09 17:01 upstream 2d3090a8aeb5 c36c07f6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/08 06:14 upstream 4549871118cf cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/05 10:46 upstream ddd664bbff63 48b6c3fa .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/04 06:41 upstream ba3e43a9e601 197909be .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/06/02 12:35 upstream 6f3ed7fec72f 62fe1528 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/05/29 07:21 upstream 8fde5d1d47f6 4624854e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/05/15 20:17 upstream 70eda68668d1 9cd3beaa .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/03/07 10:09 upstream 651690480a96 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/02/24 10:45 upstream 7dff99b35460 96b1aa46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2026/01/08 23:00 upstream 79b95d74470d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in alloc_pid / copy_process
2021/01/17 10:24 upstream 0da0a8a0a0e1 813be542 .config console log report info ci2-upstream-kcsan-gce
2020/06/08 23:26 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 0d60b78a .config console log report ci2-upstream-kcsan-gce
2020/06/05 14:51 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 d36418e9 .config console log report ci2-upstream-kcsan-gce
2019/11/20 23:46 https://github.com/google/ktsan.git kcsan 5863cc791e4c 8098ea0f .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.