vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat_one: 0xffff888195633400: Data of RX-looped back packet (a8 9e 0c a8 35 a5 ff) doesn't match TX data (d3 cd 5f 2a 6b 76 09)! ================================================================== BUG: KCSAN: data-race in can_receive / can_receive write to 0xffff88818861c1e8 of 8 bytes by interrupt on cpu 1: can_receive+0x78/0x220 net/can/af_can.c:652 can_rcv+0x9e/0x170 net/can/af_can.c:696 __netif_receive_skb_one_core net/core/dev.c:5462 [inline] __netif_receive_skb+0x8b/0x1b0 net/core/dev.c:5576 process_backlog+0x23f/0x3e0 net/core/dev.c:6452 __napi_poll+0x65/0x3f0 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x29e/0x650 net/core/dev.c:7174 __do_softirq+0x158/0x2de kernel/softirq.c:558 run_ksoftirqd+0x1f/0x30 kernel/softirq.c:920 smpboot_thread_fn+0x308/0x4a0 kernel/smpboot.c:164 kthread+0x2c7/0x2e0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 read to 0xffff88818861c1e8 of 8 bytes by interrupt on cpu 0: can_receive+0x69/0x220 net/can/af_can.c:652 can_rcv+0x9e/0x170 net/can/af_can.c:696 __netif_receive_skb_one_core net/core/dev.c:5462 [inline] __netif_receive_skb+0x8b/0x1b0 net/core/dev.c:5576 process_backlog+0x23f/0x3e0 net/core/dev.c:6452 __napi_poll+0x65/0x3f0 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x29e/0x650 net/core/dev.c:7174 __do_softirq+0x158/0x2de kernel/softirq.c:558 __irq_exit_rcu kernel/softirq.c:636 [inline] irq_exit_rcu+0x37/0x70 kernel/softirq.c:648 sysvec_call_function_single+0x8c/0xb0 arch/x86/kernel/smp.c:243 asm_sysvec_call_function_single+0x12/0x20 is_atomic kernel/kcsan/core.c:243 [inline] should_watch kernel/kcsan/core.c:271 [inline] check_access kernel/kcsan/core.c:640 [inline] __tsan_read8+0x11e/0x180 kernel/kcsan/core.c:864 native_save_fl arch/x86/include/asm/irqflags.h:35 [inline] arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] arch_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] _raw_spin_lock_irqsave+0x38/0xa0 kernel/locking/spinlock.c:162 __wake_up_common_lock kernel/sched/wait.c:137 [inline] __wake_up+0x68/0xc0 kernel/sched/wait.c:157 netlink_unlock_table net/netlink/af_netlink.c:477 [inline] netlink_broadcast+0xa2e/0xad0 net/netlink/af_netlink.c:1520 uevent_net_broadcast_untagged lib/kobject_uevent.c:331 [inline] kobject_uevent_net_broadcast lib/kobject_uevent.c:409 [inline] kobject_uevent_env+0x8c9/0xc40 lib/kobject_uevent.c:593 kobject_uevent+0x18/0x20 lib/kobject_uevent.c:642 __loop_clr_fd+0x4a3/0x6c0 drivers/block/loop.c:1150 loop_clr_fd drivers/block/loop.c:1237 [inline] lo_ioctl+0x985/0x1270 drivers/block/loop.c:1562 blkdev_ioctl+0x20e/0x440 block/ioctl.c:609 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x000000000000072d -> 0x000000000000072e Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 13136 Comm: syz-executor.5 Not tainted 5.16.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ================================================================== vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_dat: no tx connection found vcan0: j1939_xtp_rx_dat: no rx connection found vcan0: j1939_xtp_rx_rts_session_active: 0xffff888198387200: connection exists (00 00). last cmd: 16 vcan0: j1939_xtp_rx_abort_one: 0xffff8881992cb600: 0x00000: (1) Already in one or more connection managed sessions and cannot support another. vcan0: j1939_xtp_rx_abort_one: 0xffff888198387200: 0x00000: (1) Already in one or more connection managed sessions and cannot support another. vcan0: j1939_tp_rxtimer: 0xffff888198204800: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff888198204800: 0x3ff01: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_tp_rxtimer: 0xffff8881992cba00: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff8881992cba00: 0x3ff00: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_tp_rxtimer: 0xffff8881992cbe00: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff8881992cbe00: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_xtp_rx_rts_session_active: 0xffff8881992bfa00: connection exists (00 00). last cmd: 16 vcan0: j1939_xtp_rx_abort_one: 0xffff8881997abe00: 0x00000: (1) Already in one or more connection managed sessions and cannot support another. vcan0: j1939_xtp_rx_abort_one: 0xffff8881992bfa00: 0x00000: (1) Already in one or more connection managed sessions and cannot support another.