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BUG: KMSAN: uninit-value in kmsan_check_skb+0x3c/0x240 mm/kmsan/kmsan_hooks.c:275
CPU: 1 PID: 8470 Comm: kworker/u4:1 Not tainted 5.10.0-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+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118
 kmsan_internal_check_memory+0x202/0x520 mm/kmsan/kmsan.c:402
 kmsan_check_skb+0x3c/0x240 mm/kmsan/kmsan_hooks.c:275
 pfifo_fast_dequeue+0x1031/0x1190 net/sched/sch_generic.c:659
 dequeue_skb+0x4ad/0x3680 net/sched/sch_generic.c:264
 qdisc_restart net/sched/sch_generic.c:367 [inline]
 __qdisc_run+0x101/0x490 net/sched/sch_generic.c:385
 qdisc_run include/net/pkt_sched.h:131 [inline]
 __dev_xmit_skb net/core/dev.c:3755 [inline]
 __dev_queue_xmit+0x26a1/0x4590 net/core/dev.c:4108
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4173
 batadv_send_skb_packet+0x622/0x970 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:394 [inline]
 batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:420 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0xb2d/0xef0 net/batman-adv/bat_iv_ogm.c:1712
 process_one_work+0x1219/0x1fe0 kernel/workqueue.c:2272
 worker_thread+0x123c/0x2730 kernel/workqueue.c:2418
 kthread+0x51c/0x560 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:226
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:246
 __msan_memcpy+0x46/0x60 mm/kmsan/kmsan_instr.c:110
 pskb_expand_head+0x3d6/0x1e20 net/core/skbuff.c:1631
 __skb_cow include/linux/skbuff.h:3165 [inline]
 skb_cow_head include/linux/skbuff.h:3199 [inline]
 batadv_skb_head_push+0x2cc/0x410 net/batman-adv/soft-interface.c:75
 batadv_send_skb_packet+0x1ed/0x970 net/batman-adv/send.c:86
 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:394 [inline]
 batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:420 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0xb2d/0xef0 net/batman-adv/bat_iv_ogm.c:1712
 process_one_work+0x1219/0x1fe0 kernel/workqueue.c:2272
 worker_thread+0x123c/0x2730 kernel/workqueue.c:2418
 kthread+0x51c/0x560 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:121
 kmsan_alloc_page+0xd3/0x1f0 mm/kmsan/kmsan_shadow.c:274
 __alloc_pages_nodemask+0x827/0xf90 mm/page_alloc.c:4989
 __alloc_pages include/linux/gfp.h:511 [inline]
 __alloc_pages_node include/linux/gfp.h:524 [inline]
 alloc_pages_node include/linux/gfp.h:538 [inline]
 __page_frag_cache_refill mm/page_alloc.c:5065 [inline]
 page_frag_alloc+0x357/0x890 mm/page_alloc.c:5095
 __netdev_alloc_skb+0xbe2/0xc40 net/core/skbuff.c:456
 netdev_alloc_skb include/linux/skbuff.h:2826 [inline]
 dev_alloc_skb include/linux/skbuff.h:2839 [inline]
 __ieee80211_beacon_get+0x1202/0x3430 net/mac80211/tx.c:4837
 ieee80211_beacon_get_tim+0x114/0x830 net/mac80211/tx.c:4951
 ieee80211_beacon_get include/net/mac80211.h:4912 [inline]
 mac80211_hwsim_beacon_tx+0x1ce/0xd30 drivers/net/wireless/mac80211_hwsim.c:1729
 __iterate_interfaces+0x4ed/0x7a0 net/mac80211/util.c:792
 ieee80211_iterate_active_interfaces_atomic+0xbb/0xd0 net/mac80211/util.c:828
 mac80211_hwsim_beacon+0x11a/0x2e0 drivers/net/wireless/mac80211_hwsim.c:1782
 __run_hrtimer+0x48b/0xd20 kernel/time/hrtimer.c:1519
 __hrtimer_run_queues kernel/time/hrtimer.c:1583 [inline]
 hrtimer_run_softirq+0x3bf/0x690 kernel/time/hrtimer.c:1600
 __do_softirq+0x1a9/0x6fa kernel/softirq.c:298

Bytes 52-53 of 74 are uninitialized
Memory access of size 74 starts at ffff88807740b040
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