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BUG: KMSAN: uninit-value in can_receive+0x26b/0x630 net/can/af_can.c:652
CPU: 1 PID: 15 Comm: ksoftirqd/1 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+0x5f/0xa0 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+0x1ec/0x640 net/core/dev.c:5400
 process_backlog+0x523/0xc10 net/core/dev.c:6242
 napi_poll+0x4aa/0x1090 net/core/dev.c:6688
 net_rx_action+0x35c/0xd40 net/core/dev.c:6758
 __do_softirq+0x1b9/0x7ed kernel/softirq.c:298
 run_ksoftirqd+0x20/0x40 kernel/softirq.c:652
 smpboot_thread_fn+0x5f5/0xa90 kernel/smpboot.c:165
 kthread+0x51c/0x560 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:129 [inline]
 kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:112
 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2903 [inline]
 __kmalloc_node_track_caller+0x7de/0x1320 mm/slub.c:4507
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x309/0xae0 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+0x40cb/0x7950 net/can/j1939/transport.c:1116
 __run_hrtimer+0x478/0xec0 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+0x1b9/0x7ed kernel/softirq.c:298
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