syzbot


KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup (7)

Status: moderation: reported on 2026/01/06 11:13
Subsystems: wireguard
[Documentation on labels]
Reported-by: syzbot+1ba01f5dd6b508ce408b@syzkaller.appspotmail.com
First crash: 97d, last: 20d
✨ AI Jobs (3)
ID Workflow Result Correct Bug Created Started Finished Revision Error
58ea43f9-efee-475b-bb29-de708e7aeddc repro KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup (7) 2026/03/07 06:51 2026/03/07 06:51 2026/03/07 07:00 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
a05a7809-fc64-4888-9672-a25bfe4885c7 assessment-kcsan Benign: ✅  Confident: ✅  KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup (7) 2026/02/24 18:48 2026/02/24 18:48 2026/02/24 18:58 305c0ec5cd886e2d13738e28e1b2df9b0ec20fc9
fbd40482-b79d-41b4-8245-7ce95f3b49be assessment-kcsan 💥 KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup (7) 2026/01/09 23:07 2026/01/09 23:07 2026/01/09 23:26 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 monitor your current usage, head to: https://ai.dev/rate-limit. * Quota exceeded for metric: generativelanguage.googleapis.com/generate_requests_per_model_per_day, limit: 0, Status: RESOURCE_EXHAUSTED, Details: [map[@type:type.googleapis.com/google.rpc.Help links:[map[description:Learn more about Gemini API quotas url:https://ai.google.dev/gemini-api/docs/rate-limits]]] map[@type:type.googleapis.com/google.rpc.QuotaFailure violations:[map[quotaId:GenerateRequestsPerDayPerProjectPerModel quotaMetric:generativelanguage.googleapis.com/generate_requests_per_model_per_day]]] map[@type:type.googleapis.com/google.rpc.DebugInfo detail:[ORIGINAL ERROR] generic::resource_exhausted: 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 monitor your current usage, head to: https://ai.dev/rate-limit. * Quota exceeded for metric: generativelanguage.googleapis.com/generate_requests_per_model_per_day, limit: 0 [google.rpc.error_details_ext] { 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 monitor your current usage, head to: https://ai.dev/rate-limit. \n* Quota exceeded for metric: generativelanguage.googleapis.com/generate_requests_per_model_per_day, limit: 0" details { type_url: "type.googleapis.com/language_labs.genai.debug.GeminiApiDebugInfo" value: "RM\nK\nEgenerativelanguage.googleapis.com/generate_requests_per_model_per_day\030\000\"\000" } details { [type.googleapis.com/google.rpc.Help] { links { description: "Learn more about Gemini API quotas" url: "https://ai.google.dev/gemini-api/docs/rate-limits" } } } details { [type.googleapis.com/google.rpc.QuotaFailure] { violations { quota_metric: "generativelanguage.googleapis.com/generate_requests_per_model_per_day" quota_id: "GenerateRequestsPerDayPerProjectPerModel" } } } }]]
Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup wireguard 6 1 1909d 1909d 0/29 auto-closed as invalid on 2021/01/17 16:47
upstream KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup (5) wireguard 6 3 398d 446d 0/29 auto-obsoleted due to no activity on 2025/03/30 05:54
upstream KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup (4) wireguard 6 8 503d 617d 0/29 auto-obsoleted due to no activity on 2024/11/23 16:43
upstream KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup (3) wireguard 6 2 717d 735d 0/29 auto-obsoleted due to no activity on 2024/04/24 09:43
upstream KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup (6) wireguard 6 3 183d 237d 0/29 auto-obsoleted due to no activity on 2025/10/30 17:16
upstream KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup (2) wireguard 6 1 1526d 1526d 0/29 auto-closed as invalid on 2022/02/04 17:58

Sample crash report:
==================================================================
BUG: KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup

write to 0xffff88811ac6ce4c of 4 bytes by task 3161 on cpu 1:
 wg_index_hashtable_insert+0xe3/0x2b0 drivers/net/wireguard/peerlookup.c:132
 wg_noise_handshake_create_response+0x6ed/0x790 drivers/net/wireguard/noise.c:713
 wg_packet_send_handshake_response+0x6d/0x120 drivers/net/wireguard/send.c:94
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:154 [inline]
 wg_packet_handshake_receive_worker+0x3cc/0x5d0 drivers/net/wireguard/receive.c:213
 process_one_work kernel/workqueue.c:3275 [inline]
 process_scheduled_works+0x4de/0x9e0 kernel/workqueue.c:3358
 worker_thread+0x581/0x770 kernel/workqueue.c:3439
 kthread+0x22a/0x280 kernel/kthread.c:467
 ret_from_fork+0x150/0x360 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff88811ac6ce4c of 4 bytes by task 32094 on cpu 0:
 wg_index_hashtable_lookup+0x6b/0x130 drivers/net/wireguard/peerlookup.c:211
 wg_noise_handshake_consume_response+0x12a/0x910 drivers/net/wireguard/noise.c:747
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:166 [inline]
 wg_packet_handshake_receive_worker+0x3da/0x5d0 drivers/net/wireguard/receive.c:213
 process_one_work kernel/workqueue.c:3275 [inline]
 process_scheduled_works+0x4de/0x9e0 kernel/workqueue.c:3358
 worker_thread+0x581/0x770 kernel/workqueue.c:3439
 kthread+0x22a/0x280 kernel/kthread.c:467
 ret_from_fork+0x150/0x360 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0xaa486204 -> 0x89582769

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 32094 Comm: kworker/0:3 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: wg-kex-wg1 wg_packet_handshake_receive_worker
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/15 10:26 upstream ca4ee40bf13d 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup
2026/01/05 19:40 upstream 3609fa95fb0f d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup
2025/11/30 09:38 upstream 6bda50f4333f d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in wg_index_hashtable_insert / wg_index_hashtable_lookup
* Struck through repros no longer work on HEAD.