KCSAN: data-race in wg_packet_encrypt_worker / wg_packet_encrypt

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision
ffbd27e1	assessment-security	DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ✅ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ✅ VMHostTrigger: ❌	❓	KCSAN: data-race in wg_packet_encrypt_worker / wg_packet_encrypt_worker	2026/08/20 00:00	2026/08/20 00:00	2026/08/20 00:31	1e72964b
e8a9e30e	assessment-kcsan	Benign: ✅	❓	KCSAN: data-race in wg_packet_encrypt_worker / wg_packet_encrypt_worker	2026/08/18 19:12	2026/08/18 19:12	2026/08/18 19:40	1e72964b

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[syzbot] [wireguard?] KCSAN: data-race in wg_packet_encrypt_worker / wg_packet_encrypt_worker	0 (1)	2026/08/19 12:07

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[syzbot] [wireguard?] KCSAN: data-race in wg_packet_encrypt_worker / wg_packet_encrypt_worker

0 (1)

2026/08/19 12:07

================================================================== BUG: KCSAN: data-race in wg_packet_encrypt_worker / wg_packet_encrypt_worker read to 0xffff88811ac90080 of 4 bytes by task 3410 on cpu 0: wg_cpumask_choose_online drivers/net/wireguard/queueing.h:107 [inline] wg_queue_enqueue_per_peer_tx drivers/net/wireguard/queueing.h:183 [inline] wg_packet_encrypt_worker+0x9f5/0xe90 drivers/net/wireguard/send.c:305 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3405 worker_thread+0x569/0x750 kernel/workqueue.c:3486 kthread+0x221/0x270 kernel/kthread.c:436 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 write to 0xffff88811ac90080 of 4 bytes by task 15243 on cpu 1: wg_cpumask_choose_online drivers/net/wireguard/queueing.h:110 [inline] wg_queue_enqueue_per_peer_tx drivers/net/wireguard/queueing.h:183 [inline] wg_packet_encrypt_worker+0xcca/0xe90 drivers/net/wireguard/send.c:305 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3405 worker_thread+0x569/0x750 kernel/workqueue.c:3486 kthread+0x221/0x270 kernel/kthread.c:436 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 value changed: 0x00000002 -> 0x00000000 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 15243 Comm: kworker/1:19 Tainted: G W syzkaller #0 PREEMPT(lazy) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: wg-crypt-wg0 wg_packet_encrypt_worker ==================================================================

Crashes (1):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2026/08/18 19:12	upstream	0f23d56f17fd	1e72964b	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-upstream-kcsan-gce	KCSAN: data-race in wg_packet_encrypt_worker / wg_packet_encrypt_worker

Crashes (1):

Assets (help?)