=====================================================
BUG: KMSAN: uninit-value in sctp_sf_ootb+0x82d/0xce0 net/sctp/sm_statefuns.c:3718
 sctp_sf_ootb+0x82d/0xce0 net/sctp/sm_statefuns.c:3718
 sctp_do_sm+0x181/0x93d0 net/sctp/sm_sideeffect.c:1166
 sctp_endpoint_bh_rcv+0xc38/0xf90 net/sctp/endpointola.c:407
 sctp_inq_push+0x2ef/0x380 net/sctp/inqueue.c:88
 sctp_rcv+0x3831/0x3b20 net/sctp/input.c:243
 sctp4_rcv+0x42/0x50 net/sctp/protocol.c:1159
 ip_protocol_deliver_rcu+0xb51/0x13d0 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x336/0x500 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ip_local_deliver+0x21f/0x490 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:460 [inline]
 ip_rcv_finish+0x4a2/0x520 net/ipv4/ip_input.c:449
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ip_rcv+0xcd/0x380 net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core net/core/dev.c:5666 [inline]
 __netif_receive_skb+0x319/0xa00 net/core/dev.c:5779
 netif_receive_skb_internal net/core/dev.c:5865 [inline]
 netif_receive_skb+0x58/0x660 net/core/dev.c:5924
 tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1550
 tun_get_user+0x5783/0x6c60 drivers/net/tun.c:2007
 tun_chr_write_iter+0x3ac/0x5d0 drivers/net/tun.c:2053
 new_sync_write fs/read_write.c:590 [inline]
 vfs_write+0xb2b/0x1540 fs/read_write.c:683
 ksys_write+0x24f/0x4c0 fs/read_write.c:736
 __do_sys_write fs/read_write.c:748 [inline]
 __se_sys_write fs/read_write.c:745 [inline]
 __ia32_sys_write+0x91/0xe0 fs/read_write.c:745
 ia32_sys_call+0x2e34/0x40d0 arch/x86/include/generated/asm/syscalls_32.h:5
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4091 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 kmem_cache_alloc_node_noprof+0x6bf/0xb80 mm/slub.c:4186
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:587
 __alloc_skb+0x363/0x7b0 net/core/skbuff.c:678
 alloc_skb include/linux/skbuff.h:1322 [inline]
 alloc_skb_with_frags+0xc8/0xd00 net/core/skbuff.c:6612
 sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2883
 tun_alloc_skb drivers/net/tun.c:1526 [inline]
 tun_get_user+0x20f4/0x6c60 drivers/net/tun.c:1851
 tun_chr_write_iter+0x3ac/0x5d0 drivers/net/tun.c:2053
 new_sync_write fs/read_write.c:590 [inline]
 vfs_write+0xb2b/0x1540 fs/read_write.c:683
 ksys_write+0x24f/0x4c0 fs/read_write.c:736
 __do_sys_write fs/read_write.c:748 [inline]
 __se_sys_write fs/read_write.c:745 [inline]
 __ia32_sys_write+0x91/0xe0 fs/read_write.c:745
 ia32_sys_call+0x2e34/0x40d0 arch/x86/include/generated/asm/syscalls_32.h:5
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 0 UID: 0 PID: 16130 Comm: syz.3.3107 Not tainted 6.12.0-rc5-syzkaller-00005-ge42b1a9a2557 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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