syzbot


KCSAN: data-race in data_push_tail / vsnprintf (9)

Status: moderation: reported on 2025/02/21 08:47
Subsystems: usb
[Documentation on labels]
Reported-by: syzbot+504460beb7923d347fba@syzkaller.appspotmail.com
First crash: 368d, last: 9h10m
Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in data_push_tail / vsnprintf (6) ext4 6 23 610d 690d 0/29 auto-obsoleted due to no activity on 2024/03/31 12:46
upstream KCSAN: data-race in data_push_tail / vsnprintf (4) ext4 6 4 943d 1030d 0/29 auto-obsoleted due to no activity on 2023/05/03 19:58
upstream KCSAN: data-race in data_push_tail / vsnprintf (3) kernel 6 8 1154d 1253d 0/29 auto-closed as invalid on 2022/10/04 16:48
upstream KCSAN: data-race in data_push_tail / vsnprintf (7) block batman 6 2 536d 563d 0/29 auto-obsoleted due to no activity on 2024/06/13 03:32
upstream KCSAN: data-race in data_push_tail / vsnprintf (2) ext4 6 1 1310d 1310d 0/29 auto-closed as invalid on 2022/05/01 03:50
upstream KCSAN: data-race in data_push_tail / vsnprintf (5) block net 6 2 853d 881d 0/29 closed as invalid on 2023/06/28 10:46
upstream KCSAN: data-race in data_push_tail / vsnprintf (8) bridge ext4 6 4 438d 477d 0/29 auto-obsoleted due to no activity on 2024/09/19 07:21
upstream KCSAN: data-race in data_push_tail / vsnprintf usb 6 36 1375d 1688d 0/29 auto-closed as invalid on 2022/02/26 00:52

Sample crash report:
Bluetooth: hci0: command 0x1003 tx timeout
==================================================================
BUG: KCSAN: data-race in data_push_tail / vsnprintf

write to 0xffffffff88e84290 of 13 bytes by task 3615 on cpu 1:
 vsnprintf+0x2ce/0x890 lib/vsprintf.c:2878
 vscnprintf+0x41/0x90 lib/vsprintf.c:2991
 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2189
 vprintk_store+0x599/0x860 kernel/printk/printk.c:2309
 vprintk_emit+0x10d/0x580 kernel/printk/printk.c:2399
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2448
 bt_err+0x9d/0xd0 net/bluetooth/lib.c:296
 __hci_cmd_sync_status_sk net/bluetooth/hci_sync.c:271 [inline]
 __hci_cmd_sync_status net/bluetooth/hci_sync.c:287 [inline]
 hci_read_local_features_sync net/bluetooth/hci_sync.c:3703 [inline]
 hci_init_stage_sync net/bluetooth/hci_sync.c:3618 [inline]
 hci_init1_sync net/bluetooth/hci_sync.c:3750 [inline]
 hci_init_sync net/bluetooth/hci_sync.c:4862 [inline]
 hci_dev_init_sync net/bluetooth/hci_sync.c:5054 [inline]
 hci_dev_open_sync+0xfa4/0x2290 net/bluetooth/hci_sync.c:5132
 hci_dev_do_open net/bluetooth/hci_core.c:430 [inline]
 hci_power_on+0xef/0x390 net/bluetooth/hci_core.c:959
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3346
 worker_thread+0x582/0x770 kernel/workqueue.c:3427
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x122/0x1b0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffffffff88e84298 of 8 bytes by task 7102 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:591 [inline]
 data_push_tail+0xfd/0x420 kernel/printk/printk_ringbuffer.c:676
 data_alloc+0xfb/0x2e0 kernel/printk/printk_ringbuffer.c:1061
 prb_reserve+0x807/0xaf0 kernel/printk/printk_ringbuffer.c:1685
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2299
 vprintk_emit+0x10d/0x580 kernel/printk/printk.c:2399
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2448
 bt_err+0x9d/0xd0 net/bluetooth/lib.c:296
 hci_cmd_timeout+0x97/0x140 net/bluetooth/hci_core.c:1469
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3346
 worker_thread+0x582/0x770 kernel/workqueue.c:3427
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x122/0x1b0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000000fffff8ef -> 0x3a30696368203a68

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 7102 Comm: kworker/u9:4 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: hci0 hci_cmd_timeout
==================================================================
Bluetooth: hci1: command 0x1003 tx timeout

Crashes (128):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/27 16:28 upstream dcb6fa37fd7b fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/26 19:35 upstream dbfc6422a34d c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/25 02:38 upstream d2818517e348 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/22 10:18 upstream 552c50713f27 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/17 18:32 upstream cf1ea8854e4f 7adf5298 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/15 15:26 upstream 9b332cece987 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/13 11:54 upstream 3a8660878839 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/12 19:24 upstream 8765f467912f ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/10 05:19 upstream 5472d60c129f ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/09 22:02 upstream ec714e371f22 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/08 13:37 upstream 0d97f2067c16 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/08 09:52 upstream 971199ad2a0f 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/05 01:02 upstream d104e3d17f7b 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/04 15:33 upstream cbf33b8e0b36 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/04 00:05 upstream 9b0d551bcc05 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/10/02 02:17 upstream 080ffb4bec4d 267f56c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/29 01:03 upstream 8f9736633f8c 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/27 13:39 upstream fec734e8d564 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/26 05:55 upstream 4ff71af020ae 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/25 09:52 upstream bf40f4b87761 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/23 16:53 upstream cec1e6e5d1ab e667a34f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/22 08:12 upstream 2d5bd41a4505 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/21 01:33 upstream 3b08f56fbbb9 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/19 18:13 upstream 097a6c336d00 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/19 04:56 upstream cbf658dd0941 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/15 00:30 upstream 79e8447ec662 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/14 01:02 upstream 5cd64d4f9268 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/13 12:52 upstream 320475fbd590 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/08 23:35 upstream f777d1112ee5 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/07 00:41 upstream b236920731dd d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/06 14:35 upstream d1d10cea0895 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/06 07:06 upstream c8ed9b5c02a5 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/04 13:51 upstream b9a10f876409 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/09/02 05:14 upstream b320789d6883 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/29 22:01 upstream fb679c832b64 3e1beec6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/28 02:52 upstream 39f90c196721 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/17 03:27 upstream 90d970cade8e 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/16 07:49 upstream dfd4b508c8c6 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/15 18:45 upstream ee94b00c1a64 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/15 11:30 upstream 24ea63ea3877 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/14 00:37 upstream dfc0f6373094 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/13 06:11 upstream 0e39a731820a 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/12 09:54 upstream 53e760d89498 c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/10 06:05 upstream 561c80369df0 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/09 13:32 upstream 2988dfed8a5d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/08 23:22 upstream 37816488247d 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/05 08:29 upstream 7e161a991ea7 f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/04 23:26 upstream d632ab86aff2 f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/08/03 23:29 upstream 352af6a011d5 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
2025/02/07 10:10 upstream bb066fe812d6 53657d1b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / vsnprintf
* Struck through repros no longer work on HEAD.