KCSAN: data-race in _copy_from_iter / bcm_can

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision	Error
2d04eae2-9bfc-40df-84c1-462b424ed9dd	repro-c	Reproduced: ✅	❓	KCSAN: data-race in _copy_from_iter / bcm_can_tx	2026/05/19 12:52	2026/05/19 15:21	2026/05/19 15:28	1d9407ad5a662c921fc0d659cf022b438c0bde91
8f11f345-d851-4e6d-a826-7536b5780dd9	repro		💥	KCSAN: data-race in _copy_from_iter / bcm_can_tx	2026/05/19 12:52	2026/05/19 15:02	2026/05/19 15:21	1d9407ad5a662c921fc0d659cf022b438c0bde91	Basic kernel testing failed: KCSAN: data-race in clocksource_watchdog / watchdog_check_skew ================================================================== BUG: KCSAN: data-race in clocksource_watc... truncated to first 200 bytes; open job for full error
a20cf092-9add-4456-ae13-3ea12a8e5c0d	assessment-security	DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌	❓	KCSAN: data-race in _copy_from_iter / bcm_can_tx	2026/05/16 03:25	2026/05/16 03:25	2026/05/16 03:29	efdaf0f9b8bfc56ea6d17bea15a64f4591cc712d
74442fb7-40d9-4e1e-8705-0fa53344aca5	assessment-kcsan	Benign: ❌ Confident: ✅	❓	KCSAN: data-race in _copy_from_iter / bcm_can_tx	2026/04/04 19:30	2026/04/04 19:30	2026/04/04 20:03	4440e7c2e964875f9e35dba6deda12c2195f19d3

Title	Replies (including bot)	Last reply
[syzbot] [can?] KCSAN: data-race in _copy_from_iter / bcm_can_tx	0 (1)	2026/04/06 20:57

Title

Replies (including bot)

Last reply

[syzbot] [can?] KCSAN: data-race in _copy_from_iter / bcm_can_tx

0 (1)

2026/04/06 20:57

================================================================== BUG: KCSAN: data-race in _copy_from_iter / bcm_can_tx read to 0xffff8881242845c0 of 72 bytes by interrupt on cpu 0: skb_put_data include/linux/skbuff.h:2813 [inline] bcm_can_tx+0x1b3/0x4c0 net/can/bcm.c:327 bcm_tx_timeout_handler+0xe5/0x290 net/can/bcm.c:477 __run_hrtimer kernel/time/hrtimer.c:1930 [inline] __hrtimer_run_queues+0x276/0x4f0 kernel/time/hrtimer.c:1994 hrtimer_run_softirq+0xe2/0x520 kernel/time/hrtimer.c:2011 handle_softirqs+0xb9/0x280 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x42/0xd0 kernel/softirq.c:735 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x37/0x80 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 write to 0xffff8881242845c0 of 72 bytes by task 4914 on cpu 1: instrument_copy_from_user_before include/linux/instrumented.h:147 [inline] copy_from_user_iter lib/iov_iter.c:66 [inline] iterate_iovec include/linux/iov_iter.h:52 [inline] iterate_and_advance2 include/linux/iov_iter.h:304 [inline] iterate_and_advance include/linux/iov_iter.h:330 [inline] __copy_from_iter lib/iov_iter.c:261 [inline] _copy_from_iter+0x258/0xea0 lib/iov_iter.c:272 copy_from_iter include/linux/uio.h:228 [inline] copy_from_iter_full include/linux/uio.h:245 [inline] memcpy_from_msg include/linux/skbuff.h:4298 [inline] bcm_tx_setup+0xaeb/0xde0 net/can/bcm.c:965 bcm_sendmsg+0x357/0x4a0 net/can/bcm.c:1433 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg net/socket.c:802 [inline] ____sys_sendmsg+0x563/0x5b0 net/socket.c:2698 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2752 __sys_sendmsg net/socket.c:2784 [inline] __do_sys_sendmsg net/socket.c:2789 [inline] __se_sys_sendmsg net/socket.c:2787 [inline] __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2787 x64_sys_call+0x194c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 4914 Comm: syz.4.421 Tainted: G W syzkaller #0 PREEMPT(full) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 ==================================================================

Crashes (2):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2026/04/24 23:59	upstream	dd6c438c3e64	1c2b9291	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-upstream-kcsan-gce	KCSAN: data-race in _copy_from_iter / bcm_can_tx
2026/04/04 19:30	upstream	7ca6d1cfec80	4440e7c2	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-upstream-kcsan-gce	KCSAN: data-race in _copy_from_iter / bcm_can_tx

Crashes (2):

Assets (help?)