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BUG: KMSAN: uninit-value in batadv_bla_tx+0x2cec/0x4510 net/batman-adv/bridge_loop_avoidance.c:1960
CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.8.0-rc5-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+0x1df/0x240 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 batadv_bla_tx+0x2cec/0x4510 net/batman-adv/bridge_loop_avoidance.c:1960
 batadv_interface_tx+0x67c/0x2450 net/batman-adv/soft-interface.c:240
 __netdev_start_xmit include/linux/netdevice.h:4611 [inline]
 netdev_start_xmit include/linux/netdevice.h:4625 [inline]
 xmit_one net/core/dev.c:3556 [inline]
 dev_hard_start_xmit+0x50e/0xa70 net/core/dev.c:3572
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4131
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
 hsr_xmit net/hsr/hsr_forward.c:228 [inline]
 hsr_forward_do net/hsr/hsr_forward.c:285 [inline]
 hsr_forward_skb+0x1f07/0x31f0 net/hsr/hsr_forward.c:361
 hsr_handle_frame+0x3be/0x500 net/hsr/hsr_slave.c:44
 __netif_receive_skb_core+0x213f/0x5890 net/core/dev.c:5175
 __netif_receive_skb_one_core net/core/dev.c:5279 [inline]
 __netif_receive_skb net/core/dev.c:5395 [inline]
 process_backlog+0x605/0x14e0 net/core/dev.c:6239
 napi_poll net/core/dev.c:6684 [inline]
 net_rx_action+0x746/0x1aa0 net/core/dev.c:6752
 __do_softirq+0x311/0x83d kernel/softirq.c:293
 run_ksoftirqd+0x25/0x40 kernel/softirq.c:634
 smpboot_thread_fn+0x493/0x980 kernel/smpboot.c:165
 kthread+0x515/0x550 kernel/kthread.c:292
 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:293

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267
 __msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116
 pskb_expand_head+0x38b/0x1b00 net/core/skbuff.c:1636
 __skb_pad+0x47f/0x900 net/core/skbuff.c:1804
 __skb_put_padto include/linux/skbuff.h:3218 [inline]
 skb_put_padto include/linux/skbuff.h:3237 [inline]
 send_hsr_supervision_frame+0x122d/0x1500 net/hsr/hsr_device.c:299
 hsr_announce+0x1e2/0x370 net/hsr/hsr_device.c:330
 call_timer_fn+0x218/0x510 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers+0xd20/0x11c0 kernel/time/timer.c:1773
 run_timer_softirq+0x2d/0x50 kernel/time/timer.c:1786
 __do_softirq+0x311/0x83d kernel/softirq.c:293

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:144
 kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:269 [inline]
 kmsan_alloc_page+0xb9/0x180 mm/kmsan/kmsan_shadow.c:293
 __alloc_pages_nodemask+0x56a2/0x5dc0 mm/page_alloc.c:4889
 __alloc_pages include/linux/gfp.h:509 [inline]
 __alloc_pages_node include/linux/gfp.h:522 [inline]
 alloc_pages_node include/linux/gfp.h:536 [inline]
 __page_frag_cache_refill mm/page_alloc.c:4964 [inline]
 page_frag_alloc+0x3ae/0x910 mm/page_alloc.c:4994
 __napi_alloc_skb+0x193/0xa60 net/core/skbuff.c:519
 napi_alloc_skb include/linux/skbuff.h:2850 [inline]
 page_to_skb+0x1a2/0x1390 drivers/net/virtio_net.c:384
 receive_mergeable drivers/net/virtio_net.c:944 [inline]
 receive_buf+0xf9e/0x9760 drivers/net/virtio_net.c:1054
 virtnet_receive drivers/net/virtio_net.c:1346 [inline]
 virtnet_poll+0x64b/0x19f0 drivers/net/virtio_net.c:1451
 napi_poll net/core/dev.c:6684 [inline]
 net_rx_action+0x746/0x1aa0 net/core/dev.c:6752
 __do_softirq+0x311/0x83d kernel/softirq.c:293
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