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BUG: KMSAN: uninit-value in sctp_sf_ootb+0x7f1/0xcd0 net/sctp/sm_statefuns.c:3703
 sctp_sf_ootb+0x7f1/0xcd0 net/sctp/sm_statefuns.c:3703
 sctp_do_sm+0x199/0x9b90 net/sctp/sm_sideeffect.c:1167
 sctp_endpoint_bh_rcv+0xc2d/0xf80 net/sctp/endpointola.c:402
 sctp_inq_push+0x238/0x2b0 net/sctp/inqueue.c:80
 sctp_rcv+0x39fe/0x3bd0 net/sctp/input.c:258
 sctp4_rcv+0x3e/0x50 net/sctp/protocol.c:1154
 ip_protocol_deliver_rcu+0x201/0xaf0 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2a5/0x3a0 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ip_local_deliver+0x278/0x4a0 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:455 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:449 [inline]
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ip_rcv+0x527/0x7c0 net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core net/core/dev.c:5489 [inline]
 __netif_receive_skb+0x1b3/0x5d0 net/core/dev.c:5603
 netif_receive_skb_internal+0x53/0x340 net/core/dev.c:5689
 netif_receive_skb+0x35/0x350 net/core/dev.c:5748
 tun_rx_batched+0x837/0x930
 tun_get_user+0x3bc6/0x4300 drivers/net/tun.c:2006
 tun_chr_write_iter+0x3ab/0x5d0 drivers/net/tun.c:2036
 call_write_iter include/linux/fs.h:2199 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x830/0x1570 fs/read_write.c:584
 ksys_write+0x21b/0x4e0 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+0x8f/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:742 [inline]
 slab_alloc_node mm/slub.c:3398 [inline]
 __kmem_cache_alloc_node+0x6ee/0xc90 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc_node_track_caller+0x114/0x3c0 mm/slab_common.c:975
 kmalloc_reserve net/core/skbuff.c:437 [inline]
 __alloc_skb+0x34a/0xca0 net/core/skbuff.c:509
 alloc_skb include/linux/skbuff.h:1267 [inline]
 alloc_skb_with_frags+0xb9/0xba0 net/core/skbuff.c:6126
 sock_alloc_send_pskb+0xaa8/0xc30 net/core/sock.c:2719
 tun_alloc_skb drivers/net/tun.c:1523 [inline]
 tun_get_user+0x174b/0x4300 drivers/net/tun.c:1836
 tun_chr_write_iter+0x3ab/0x5d0 drivers/net/tun.c:2036
 call_write_iter include/linux/fs.h:2199 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x830/0x1570 fs/read_write.c:584
 ksys_write+0x21b/0x4e0 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+0x8f/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 1 PID: 3584 Comm: syz-executor.0 Not tainted 6.1.0-syzkaller-00014-g5c6259d6d19f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
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