=====================================================
BUG: KMSAN: uninit-value in vring_map_one_sg drivers/virtio/virtio_ring.c:341 [inline]
BUG: KMSAN: uninit-value in virtqueue_add_split drivers/virtio/virtio_ring.c:546 [inline]
BUG: KMSAN: uninit-value in virtqueue_add+0x1d8a/0x6220 drivers/virtio/virtio_ring.c:1818
 vring_map_one_sg drivers/virtio/virtio_ring.c:341 [inline]
 virtqueue_add_split drivers/virtio/virtio_ring.c:546 [inline]
 virtqueue_add+0x1d8a/0x6220 drivers/virtio/virtio_ring.c:1818
 virtqueue_add_outbuf+0x91/0xc0 drivers/virtio/virtio_ring.c:1875
 xmit_skb drivers/net/virtio_net.c:1794 [inline]
 start_xmit+0x13fe/0x2200 drivers/net/virtio_net.c:1821
 __netdev_start_xmit include/linux/netdevice.h:4805 [inline]
 netdev_start_xmit include/linux/netdevice.h:4819 [inline]
 xmit_one+0x14e/0x5f0 net/core/dev.c:3590
 dev_hard_start_xmit+0xe5/0x370 net/core/dev.c:3606
 sch_direct_xmit+0x3f1/0xdb0 net/sched/sch_generic.c:342
 __dev_xmit_skb+0xbe9/0x19e0 net/core/dev.c:3817
 __dev_queue_xmit+0x12cb/0x31f0 net/core/dev.c:4221
 dev_queue_xmit include/linux/netdevice.h:2994 [inline]
 neigh_resolve_output+0x976/0xa00 net/core/neighbour.c:1528
 neigh_output include/net/neighbour.h:549 [inline]
 ip_finish_output2+0x1918/0x1b30 net/ipv4/ip_output.c:228
 __ip_finish_output+0x266/0x720
 ip_finish_output+0x3d1/0x400 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0x258/0x510 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:451 [inline]
 ip_local_out+0xe5/0x140 net/ipv4/ip_output.c:126
 iptunnel_xmit+0x744/0xcd0 net/ipv4/ip_tunnel_core.c:82
 ip_tunnel_xmit+0x3267/0x3610 net/ipv4/ip_tunnel.c:811
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 erspan_xmit+0x13d8/0x1f00 net/ipv4/ip_gre.c:715
 __netdev_start_xmit include/linux/netdevice.h:4805 [inline]
 netdev_start_xmit include/linux/netdevice.h:4819 [inline]
 xmit_one+0x14e/0x5f0 net/core/dev.c:3590
 dev_hard_start_xmit+0xe5/0x370 net/core/dev.c:3606
 sch_direct_xmit+0x3f1/0xdb0 net/sched/sch_generic.c:342
 __dev_xmit_skb+0xbe9/0x19e0 net/core/dev.c:3817
 __dev_queue_xmit+0x12cb/0x31f0 net/core/dev.c:4221
 dev_queue_xmit include/linux/netdevice.h:2994 [inline]
 neigh_resolve_output+0x976/0xa00 net/core/neighbour.c:1528
 neigh_output include/net/neighbour.h:549 [inline]
 ip_finish_output2+0x1918/0x1b30 net/ipv4/ip_output.c:228
 __ip_finish_output+0x266/0x720
 ip_finish_output+0x3d1/0x400 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0x258/0x510 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:451 [inline]
 ip_local_out+0xe5/0x140 net/ipv4/ip_output.c:126
 igmpv3_sendpack net/ipv4/igmp.c:424 [inline]
 igmpv3_send_cr net/ipv4/igmp.c:720 [inline]
 igmp_ifc_timer_expire+0x15c8/0x1f50 net/ipv4/igmp.c:810
 call_timer_fn+0x43/0x480 kernel/time/timer.c:1474
 expire_timers+0x272/0x610 kernel/time/timer.c:1519
 __run_timers+0x5bc/0x8c0 kernel/time/timer.c:1790
 run_timer_softirq+0x64/0xe0 kernel/time/timer.c:1803
 __do_softirq+0x1cc/0x7fb kernel/softirq.c:571
 invoke_softirq+0x8f/0x100 kernel/softirq.c:445
 __irq_exit_rcu kernel/softirq.c:650 [inline]
 irq_exit_rcu+0x5a/0x110 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x9a/0xc0 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x1b/0x20
 valid_section include/linux/mmzone.h:1451 [inline]
 pfn_valid include/linux/mmzone.h:1540 [inline]
 kmsan_virt_addr_valid arch/x86/include/asm/kmsan.h:50 [inline]
 virt_to_page_or_null mm/kmsan/shadow.c:76 [inline]
 kmsan_get_metadata+0x13d/0x230 mm/kmsan/shadow.c:139
 kmsan_get_shadow_origin_ptr+0x34/0xa0 mm/kmsan/shadow.c:98
 get_shadow_origin_ptr mm/kmsan/instrumentation.c:35 [inline]
 __msan_metadata_ptr_for_load_4+0x20/0x30 mm/kmsan/instrumentation.c:76
 unwind_done arch/x86/include/asm/unwind.h:50 [inline]
 arch_stack_walk+0x1c7/0x280 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0xb2/0x100 kernel/stacktrace.c:122
 kmsan_save_stack_with_flags mm/kmsan/core.c:80 [inline]
 kmsan_internal_poison_memory+0x45/0x90 mm/kmsan/core.c:65
 kmsan_slab_free+0xcd/0x130 mm/kmsan/hooks.c:88
 slab_free_hook mm/slub.c:1739 [inline]
 slab_free_freelist_hook+0x1b8/0x650 mm/slub.c:1795
 slab_free mm/slub.c:3551 [inline]
 kfree+0x207/0x9c0 mm/slub.c:4599
 batadv_mcast_mla_list_free net/batman-adv/multicast.c:639 [inline]
 __batadv_mcast_mla_update net/batman-adv/multicast.c:894 [inline]
 batadv_mcast_mla_update+0x4bde/0x4fd0 net/batman-adv/multicast.c:916
 process_one_work+0xb27/0x13e0 kernel/workqueue.c:2289
 worker_thread+0x1076/0x1d60 kernel/workqueue.c:2436
 kthread+0x31b/0x430 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

Uninit was stored to memory at:
 pskb_expand_head+0x2c2/0x1a00 net/core/skbuff.c:1704
 __skb_cow include/linux/skbuff.h:3633 [inline]
 skb_cow_head include/linux/skbuff.h:3667 [inline]
 ip_tunnel_xmit+0x2ff4/0x3610 net/ipv4/ip_tunnel.c:804
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 erspan_xmit+0x13d8/0x1f00 net/ipv4/ip_gre.c:715
 __netdev_start_xmit include/linux/netdevice.h:4805 [inline]
 netdev_start_xmit include/linux/netdevice.h:4819 [inline]
 xmit_one+0x14e/0x5f0 net/core/dev.c:3590
 dev_hard_start_xmit+0xe5/0x370 net/core/dev.c:3606
 sch_direct_xmit+0x3f1/0xdb0 net/sched/sch_generic.c:342
 __dev_xmit_skb+0xbe9/0x19e0 net/core/dev.c:3817
 __dev_queue_xmit+0x12cb/0x31f0 net/core/dev.c:4221
 dev_queue_xmit include/linux/netdevice.h:2994 [inline]
 neigh_resolve_output+0x976/0xa00 net/core/neighbour.c:1528
 neigh_output include/net/neighbour.h:549 [inline]
 ip_finish_output2+0x1918/0x1b30 net/ipv4/ip_output.c:228
 __ip_finish_output+0x266/0x720
 ip_finish_output+0x3d1/0x400 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0x258/0x510 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:451 [inline]
 ip_local_out+0xe5/0x140 net/ipv4/ip_output.c:126
 igmpv3_sendpack net/ipv4/igmp.c:424 [inline]
 igmpv3_send_cr net/ipv4/igmp.c:720 [inline]
 igmp_ifc_timer_expire+0x15c8/0x1f50 net/ipv4/igmp.c:810
 call_timer_fn+0x43/0x480 kernel/time/timer.c:1474
 expire_timers+0x272/0x610 kernel/time/timer.c:1519
 __run_timers+0x5bc/0x8c0 kernel/time/timer.c:1790
 run_timer_softirq+0x64/0xe0 kernel/time/timer.c:1803
 __do_softirq+0x1cc/0x7fb kernel/softirq.c:571

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:755 [inline]
 slab_alloc_node mm/slub.c:3258 [inline]
 __kmalloc_node_track_caller+0x86c/0x1230 mm/slub.c:4994
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 __alloc_skb+0x34a/0xd70 net/core/skbuff.c:426
 alloc_skb include/linux/skbuff.h:1426 [inline]
 igmpv3_newpack+0x19d/0x1440 net/ipv4/igmp.c:359
 add_grhead+0x86/0x390 net/ipv4/igmp.c:440
 add_grec+0x2185/0x2380 net/ipv4/igmp.c:574
 igmpv3_send_cr net/ipv4/igmp.c:711 [inline]
 igmp_ifc_timer_expire+0x11b6/0x1f50 net/ipv4/igmp.c:810
 call_timer_fn+0x43/0x480 kernel/time/timer.c:1474
 expire_timers+0x272/0x610 kernel/time/timer.c:1519
 __run_timers+0x5bc/0x8c0 kernel/time/timer.c:1790
 run_timer_softirq+0x64/0xe0 kernel/time/timer.c:1803
 __do_softirq+0x1cc/0x7fb kernel/softirq.c:571

Bytes 38-39 of 104 are uninitialized
Memory access of size 104 starts at ffff88805b0da0c0

CPU: 0 PID: 40 Comm: kworker/u4:2 Not tainted 5.19.0-syzkaller-32655-g1b070a5d1a2c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Workqueue: bat_events batadv_mcast_mla_update
=====================================================