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BUG: KMSAN: uninit-value in ____bpf_skb_get_nlattr_nest net/core/filter.c:164 [inline]
BUG: KMSAN: uninit-value in bpf_skb_get_nlattr_nest+0x14c/0x2f0 net/core/filter.c:154
CPU: 0 PID: 216 Comm: kworker/u4:4 Not tainted 5.7.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 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
 ____bpf_skb_get_nlattr_nest net/core/filter.c:164 [inline]
 bpf_skb_get_nlattr_nest+0x14c/0x2f0 net/core/filter.c:154
 ___bpf_prog_run+0x214d/0x97a0 kernel/bpf/core.c:1516
 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681
 bpf_dispatcher_nop_func include/linux/bpf.h:545 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:599 [inline]
 bpf_prog_run_clear_cb include/linux/filter.h:721 [inline]
 run_filter net/packet/af_packet.c:2012 [inline]
 packet_rcv+0x70f/0x2160 net/packet/af_packet.c:2085
 dev_queue_xmit_nit+0x1199/0x1270 net/core/dev.c:2276
 xmit_one net/core/dev.c:3473 [inline]
 dev_hard_start_xmit+0x20f/0xab0 net/core/dev.c:3493
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4052
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085
 batadv_send_skb_packet+0x59b/0x8c0 net/batman-adv/send.c:108
 batadv_send_broadcast_skb+0x76/0x90 net/batman-adv/send.c:127
 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:393 [inline]
 batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x97e/0xd50 net/batman-adv/bat_iv_ogm.c:1710
 process_one_work+0x1555/0x1f40 kernel/workqueue.c:2268
 worker_thread+0xef6/0x2450 kernel/workqueue.c:2414
 kthread+0x4b5/0x4f0 kernel/kthread.c:269
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:353

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
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
 ___bpf_prog_run+0x6cbe/0x97a0 kernel/bpf/core.c:1391
 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681
 bpf_dispatcher_nop_func include/linux/bpf.h:545 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:599 [inline]
 bpf_prog_run_clear_cb include/linux/filter.h:721 [inline]
 run_filter net/packet/af_packet.c:2012 [inline]
 packet_rcv+0x70f/0x2160 net/packet/af_packet.c:2085
 dev_queue_xmit_nit+0x1199/0x1270 net/core/dev.c:2276
 xmit_one net/core/dev.c:3473 [inline]
 dev_hard_start_xmit+0x20f/0xab0 net/core/dev.c:3493
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4052
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085
 batadv_send_skb_packet+0x59b/0x8c0 net/batman-adv/send.c:108
 batadv_send_broadcast_skb+0x76/0x90 net/batman-adv/send.c:127
 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:393 [inline]
 batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x97e/0xd50 net/batman-adv/bat_iv_ogm.c:1710
 process_one_work+0x1555/0x1f40 kernel/workqueue.c:2268
 worker_thread+0xef6/0x2450 kernel/workqueue.c:2414
 kthread+0x4b5/0x4f0 kernel/kthread.c:269
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:353

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
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
 ___bpf_prog_run+0x6c64/0x97a0 kernel/bpf/core.c:1391
 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681
 bpf_dispatcher_nop_func include/linux/bpf.h:545 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:599 [inline]
 bpf_prog_run_clear_cb include/linux/filter.h:721 [inline]
 run_filter net/packet/af_packet.c:2012 [inline]
 packet_rcv+0x70f/0x2160 net/packet/af_packet.c:2085
 dev_queue_xmit_nit+0x1199/0x1270 net/core/dev.c:2276
 xmit_one net/core/dev.c:3473 [inline]
 dev_hard_start_xmit+0x20f/0xab0 net/core/dev.c:3493
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4052
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085
 batadv_send_skb_packet+0x59b/0x8c0 net/batman-adv/send.c:108
 batadv_send_broadcast_skb+0x76/0x90 net/batman-adv/send.c:127
 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:393 [inline]
 batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x97e/0xd50 net/batman-adv/bat_iv_ogm.c:1710
 process_one_work+0x1555/0x1f40 kernel/workqueue.c:2268
 worker_thread+0xef6/0x2450 kernel/workqueue.c:2414
 kthread+0x4b5/0x4f0 kernel/kthread.c:269
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:353

Local variable ----regs@__bpf_prog_run32 created at:
 __bpf_prog_run32+0x87/0x170 kernel/bpf/core.c:1681
 __bpf_prog_run32+0x87/0x170 kernel/bpf/core.c:1681
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