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BUG: KMSAN: uninit-value in sctp_sf_ootb+0x7f5/0xce0 net/sctp/sm_statefuns.c:3703
 sctp_sf_ootb+0x7f5/0xce0 net/sctp/sm_statefuns.c:3703
 sctp_do_sm+0x19c/0xa160 net/sctp/sm_sideeffect.c:1167
 sctp_endpoint_bh_rcv+0xc38/0xf90 net/sctp/endpointola.c:407
 sctp_inq_push+0x23e/0x2b0 net/sctp/inqueue.c:80
 sctp_rcv+0x3c1d/0x3f30 net/sctp/input.c:243
 sctp4_rcv+0x42/0x50 net/sctp/protocol.c:1160
 ip_protocol_deliver_rcu+0x264/0x1320 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2b8/0x440 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ip_local_deliver+0x241/0x4b0 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:454 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:449 [inline]
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ip_rcv+0x4b0/0x7c0 net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core net/core/dev.c:5479 [inline]
 __netif_receive_skb+0x1b8/0x5e0 net/core/dev.c:5593
 netif_receive_skb_internal net/core/dev.c:5679 [inline]
 netif_receive_skb+0x68/0x680 net/core/dev.c:5738
 tun_rx_batched+0x837/0x930
 tun_get_user+0x591d/0x7070 drivers/net/tun.c:1988
 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2034
 call_write_iter include/linux/fs.h:1851 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x834/0x1580 fs/read_write.c:584
 ksys_write+0x21f/0x4f0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x93/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook+0x12d/0xb60 mm/slab.h:774
 slab_alloc_node mm/slub.c:3452 [inline]
 kmem_cache_alloc_node+0x543/0xab0 mm/slub.c:3497
 kmalloc_reserve+0x148/0x470 net/core/skbuff.c:520
 __alloc_skb+0x3a7/0x850 net/core/skbuff.c:606
 alloc_skb include/linux/skbuff.h:1277 [inline]
 alloc_skb_with_frags+0xbd/0xbb0 net/core/skbuff.c:6318
 sock_alloc_send_pskb+0xaad/0xc30 net/core/sock.c:2734
 tun_alloc_skb drivers/net/tun.c:1528 [inline]
 tun_get_user+0x2167/0x7070 drivers/net/tun.c:1840
 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2034
 call_write_iter include/linux/fs.h:1851 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x834/0x1580 fs/read_write.c:584
 ksys_write+0x21f/0x4f0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x93/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 1 PID: 5114 Comm: syz-executor.0 Not tainted 6.3.0-rc3-syzkaller-00010-g90ea0df61c98 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/17/2023
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