KCSAN: data-race in memcpy_and_pad / zap_other

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision	Error
d96422ea-1573-414b-bea5-03db7c6efc1b	assessment-kcsan		💥	KCSAN: data-race in memcpy_and_pad / zap_other_threads (2)	2026/01/10 02:16	2026/01/10 02:16	2026/01/10 02:16	7519916073b761ced56a7b15fdeeb4674e8dc125	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

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in memcpy_and_pad / zap_other_threads (3) race:benign kernel prio:high	6				1	86d	86d	0/29	auto-obsoleted due to no activity on 2026/05/22 17:02
upstream	KCSAN: data-race in memcpy_and_pad / zap_other_threads kernel	6				2	285d	297d	0/29	auto-obsoleted due to no activity on 2025/11/04 14:25

Kernel

Title

Rank 🛈

upstream

KCSAN: data-race in memcpy_and_pad / zap_other_threads (3) race:benign kernel prio:high

86d

0/29

auto-obsoleted due to no activity on 2026/05/22 17:02

upstream

KCSAN: data-race in memcpy_and_pad / zap_other_threads kernel

285d

297d

0/29

auto-obsoleted due to no activity on 2025/11/04 14:25

================================================================== BUG: KCSAN: data-race in memcpy_and_pad / zap_other_threads read-write to 0xffff8881042a8538 of 8 bytes by task 30807 on cpu 1: task_clear_jobctl_pending kernel/signal.c:339 [inline] zap_other_threads+0x114/0x290 kernel/signal.c:1345 do_group_exit+0xe4/0x140 kernel/exit.c:1107 __do_sys_exit_group kernel/exit.c:1123 [inline] __se_sys_exit_group kernel/exit.c:1121 [inline] __x64_sys_exit_group+0x1f/0x20 kernel/exit.c:1121 x64_sys_call+0x2fff/0x3000 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xca/0x2b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff8881042a8000 of 3264 bytes by task 30808 on cpu 0: memcpy_and_pad+0x48/0x80 lib/string_helpers.c:1007 arch_dup_task_struct+0x2c/0x40 arch/x86/kernel/process.c:108 dup_task_struct+0x6e/0x950 kernel/fork.c:919 copy_process+0x37d/0x1ef0 kernel/fork.c:2052 create_io_thread+0x71/0xa0 kernel/fork.c:2599 create_worker_cont+0x5f/0x380 io_uring/io-wq.c:846 task_work_run+0x131/0x1a0 kernel/task_work.c:233 get_signal+0xe12/0xf70 kernel/signal.c:2807 arch_do_signal_or_restart+0x96/0x450 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x6a/0x740 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x1e1/0x2b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 30808 Comm: syz.6.5323 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 ==================================================================

Crashes (3):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Assets (help?)	Manager	Title
2025/12/29 15:13	upstream	7839932417dd	d6526ea3	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci2-upstream-kcsan-gce	KCSAN: data-race in memcpy_and_pad / zap_other_threads
2025/12/22 20:45	upstream	9448598b22c5	d6526ea3	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci2-upstream-kcsan-gce	KCSAN: data-race in memcpy_and_pad / zap_other_threads
2025/12/05 11:21	upstream	2061f18ad76e	d6526ea3	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci2-upstream-kcsan-gce	KCSAN: data-race in memcpy_and_pad / zap_other_threads

Crashes (3):

Assets (help?)