=====================================================
BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:167 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x376/0x1c60 lib/iov_iter.c:316
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 copyout lib/iov_iter.c:167 [inline]
 _copy_to_iter+0x376/0x1c60 lib/iov_iter.c:316
 copy_to_iter include/linux/uio.h:194 [inline]
 simple_copy_to_iter+0x68/0xa0 net/core/datagram.c:513
 __skb_datagram_iter+0x123/0xdc0 net/core/datagram.c:419
 skb_copy_datagram_iter+0x5c/0x200 net/core/datagram.c:527
 tun_put_user drivers/net/tun.c:2159 [inline]
 tun_do_read+0x2167/0x2ae0 drivers/net/tun.c:2238
 tun_chr_read_iter+0x3f0/0x670 drivers/net/tun.c:2262
 call_read_iter include/linux/fs.h:1865 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x8fc/0xf50 fs/read_write.c:470
 ksys_read+0x20f/0x4c0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x93/0xd0 fs/read_write.c:621
 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 stored to memory at:
 pskb_expand_head+0x305/0x1a10 net/core/skbuff.c:2050
 skb_expand_head+0x44c/0x870 net/core/skbuff.c:2214
 ip_finish_output2+0xc75/0x1a10 net/ipv4/ip_output.c:211
 __ip_finish_output+0x266/0x720
 ip_finish_output+0x4b/0x420 net/ipv4/ip_output.c:318
 NF_HOOK_COND include/linux/netfilter.h:292 [inline]
 ip_mc_output+0x708/0xe40 net/ipv4/ip_output.c:417
 dst_output include/net/dst.h:458 [inline]
 ip_local_out net/ipv4/ip_output.c:127 [inline]
 __ip_queue_xmit+0x1985/0x1c40 net/ipv4/ip_output.c:534
 sctp_v4_xmit+0x6a1/0xe90 net/sctp/protocol.c:1074
 sctp_packet_transmit+0x3e55/0x4150 net/sctp/output.c:653
 sctp_packet_singleton+0x2ab/0x390 net/sctp/outqueue.c:783
 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline]
 sctp_outq_flush+0x709/0x5e70 net/sctp/outqueue.c:1212
 sctp_outq_uncork+0x9c/0xb0 net/sctp/outqueue.c:764
 sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline]
 sctp_do_sm+0x8c1a/0x9380 net/sctp/sm_sideeffect.c:1169
 sctp_primitive_ASSOCIATE+0xc3/0x100 net/sctp/primitive.c:73
 sctp_sendmsg_to_asoc+0x178d/0x1ee0 net/sctp/socket.c:1840
 sctp_sendmsg+0x32b4/0x4a70 net/sctp/socket.c:2030
 inet_sendmsg+0x105/0x190 net/ipv4/af_inet.c:830
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg net/socket.c:748 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2494
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2548
 __sys_sendmsg net/socket.c:2577 [inline]
 __do_sys_sendmsg net/socket.c:2586 [inline]
 __se_sys_sendmsg net/socket.c:2584 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2584
 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+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3470 [inline]
 __kmem_cache_alloc_node+0x536/0x8d0 mm/slub.c:3509
 __do_kmalloc_node mm/slab_common.c:984 [inline]
 __kmalloc_node_track_caller+0x118/0x3c0 mm/slab_common.c:1005
 kmalloc_reserve+0x248/0x470 net/core/skbuff.c:575
 __alloc_skb+0x318/0x740 net/core/skbuff.c:644
 alloc_skb include/linux/skbuff.h:1289 [inline]
 sctp_packet_transmit+0x551/0x4150 net/sctp/output.c:598
 sctp_packet_singleton+0x2ab/0x390 net/sctp/outqueue.c:783
 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline]
 sctp_outq_flush+0x709/0x5e70 net/sctp/outqueue.c:1212
 sctp_outq_uncork+0x9c/0xb0 net/sctp/outqueue.c:764
 sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline]
 sctp_do_sm+0x8c1a/0x9380 net/sctp/sm_sideeffect.c:1169
 sctp_primitive_ASSOCIATE+0xc3/0x100 net/sctp/primitive.c:73
 sctp_sendmsg_to_asoc+0x178d/0x1ee0 net/sctp/socket.c:1840
 sctp_sendmsg+0x32b4/0x4a70 net/sctp/socket.c:2030
 inet_sendmsg+0x105/0x190 net/ipv4/af_inet.c:830
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg net/socket.c:748 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2494
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2548
 __sys_sendmsg net/socket.c:2577 [inline]
 __do_sys_sendmsg net/socket.c:2586 [inline]
 __se_sys_sendmsg net/socket.c:2584 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2584
 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

Bytes 38-41 of 572 are uninitialized
Memory access of size 572 starts at ffff88809ea490b0
Data copied to user address 00007fc6856bf960

CPU: 1 PID: 19861 Comm: syz-executor.5 Tainted: G        W          6.5.0-rc3-syzkaller-00015-g9e0ee0c7545c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
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