===================================================== BUG: KMSAN: uninit-value in can_receive+0x26b/0x630 net/can/af_can.c:652 CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.9.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x21c/0x280 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122 __msan_warning+0x55/0x90 mm/kmsan/kmsan_instr.c:201 can_receive+0x26b/0x630 net/can/af_can.c:652 can_rcv+0x1fb/0x410 net/can/af_can.c:688 __netif_receive_skb_one_core net/core/dev.c:5286 [inline] __netif_receive_skb+0x265/0x670 net/core/dev.c:5400 process_backlog+0x50d/0xba0 net/core/dev.c:6242 napi_poll+0x443/0x1100 net/core/dev.c:6688 net_rx_action+0x35c/0xd40 net/core/dev.c:6758 __do_softirq+0x2ea/0x7f5 kernel/softirq.c:299 run_ksoftirqd+0x25/0x40 kernel/softirq.c:656 smpboot_thread_fn+0x5f5/0xa90 kernel/smpboot.c:165 kthread+0x551/0x590 kernel/kthread.c:293 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:143 [inline] kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:126 kmsan_slab_alloc+0x83/0xd0 mm/kmsan/kmsan_hooks.c:80 slab_alloc_node mm/slub.c:2903 [inline] __kmalloc_node_track_caller+0x9aa/0x12f0 mm/slub.c:4507 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0x35f/0xb30 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1094 [inline] j1939_tp_tx_dat_new net/can/j1939/transport.c:575 [inline] j1939_xtp_do_tx_ctl net/can/j1939/transport.c:635 [inline] j1939_tp_tx_ctl net/can/j1939/transport.c:653 [inline] j1939_session_tx_rts net/can/j1939/transport.c:721 [inline] j1939_xtp_txnext_transmiter net/can/j1939/transport.c:853 [inline] j1939_tp_txtimer+0x4427/0x7960 net/can/j1939/transport.c:1116 __run_hrtimer+0x7cd/0xf00 kernel/time/hrtimer.c:1524 __hrtimer_run_queues kernel/time/hrtimer.c:1588 [inline] hrtimer_run_softirq+0x3bf/0x690 kernel/time/hrtimer.c:1605 __do_softirq+0x2ea/0x7f5 kernel/softirq.c:299 =====================================================