KCSAN: data-race in sg_common_write / sg_finish_rem_req (6)

Status: auto-obsoleted due to no activity on 2026/04/16 10:02
Subsystems: scsi
[Documentation on labels]
Reported-by: syzbot+3fd8cb6e827442a26422@syzkaller.appspotmail.com
First crash: 285d, last: 173d
✨ AI Jobs (3)
ID Workflow Result Correct Bug Created Started Finished Revision
d721cb12 repro KCSAN: data-race in sg_common_write / sg_finish_rem_req (6) 2026/03/08 01:03 2026/03/08 01:03 2026/03/08 01:11 31e9c887
2b3ae101 assessment-kcsan Benign: ❌ Confident: ✅ KCSAN: data-race in sg_common_write / sg_finish_rem_req (6) 2026/02/24 21:31 2026/02/24 21:31 2026/02/24 21:35 305c0ec5
ac308e26 assessment-kcsan 💥 KCSAN: data-race in sg_common_write / sg_finish_rem_req (6) 2026/01/10 03:33 2026/01/10 03:33 2026/01/10 03:52 75199160
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in sg_common_write / sg_finish_rem_req (4) scsi 6 6 536d 558d 0/29 auto-obsoleted due to no activity on 2025/04/18 04:19
upstream KCSAN: data-race in sg_common_write / sg_finish_rem_req scsi 6 3 1025d 1058d 0/29 auto-obsoleted due to no activity on 2023/11/25 03:57
upstream KCSAN: data-race in sg_common_write / sg_finish_rem_req (2) scsi 6 1 780d 780d 0/29 auto-obsoleted due to no activity on 2024/07/27 17:57
upstream KCSAN: data-race in sg_common_write / sg_finish_rem_req (5) scsi 6 7 379d 470d 0/29 auto-obsoleted due to no activity on 2025/09/21 21:52
upstream KCSAN: data-race in sg_common_write / sg_finish_rem_req (3) scsi 6 14 663d 730d 0/29 auto-obsoleted due to no activity on 2024/11/20 21:45

Sample crash report:
==================================================================
BUG: KCSAN: data-race in sg_common_write / sg_finish_rem_req

write to 0xffff888117b7b31d of 1 bytes by task 3407 on cpu 1:
 sg_unlink_reserve drivers/scsi/sg.c:2062 [inline]
 sg_finish_rem_req+0x11f/0x270 drivers/scsi/sg.c:1844
 sg_rq_end_io_usercontext+0x38/0x1c0 drivers/scsi/sg.c:1303
 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 0xffff888117b7b31d of 1 bytes by task 5818 on cpu 0:
 sg_start_req drivers/scsi/sg.c:1784 [inline]
 sg_common_write+0x952/0xc80 drivers/scsi/sg.c:802
 sg_new_write+0x7e4/0x8c0 drivers/scsi/sg.c:769
 sg_ioctl_common drivers/scsi/sg.c:933 [inline]
 sg_ioctl+0xbf8/0x1350 drivers/scsi/sg.c:1158
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583
 x64_sys_call+0x1563/0x3020 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 5818 Comm: syz.0.574 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
==================================================================

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/19 10:01 upstream 956b9cbd7f15 746545b8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in sg_common_write / sg_finish_rem_req
2025/12/28 17:44 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in sg_common_write / sg_finish_rem_req
2025/12/23 16:51 upstream b927546677c8 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in sg_common_write / sg_finish_rem_req
2025/12/05 23:22 upstream d1d36025a617 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in sg_common_write / sg_finish_rem_req
2025/11/25 05:18 upstream ac3fd01e4c1e 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in sg_common_write / sg_finish_rem_req
2025/11/22 14:32 upstream 2eba5e05d9bc 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in sg_common_write / sg_finish_rem_req
2025/11/20 14:07 upstream 23cb64fb7625 2cc4c24a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in sg_common_write / sg_finish_rem_req
2025/11/01 19:45 upstream 691d401c7e0e 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in sg_common_write / sg_finish_rem_req
2025/10/30 14:38 upstream e53642b87a4f fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in sg_common_write / sg_finish_rem_req
* Struck through repros no longer work on HEAD.