=====================================================
BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:121 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_user+0x1c9/0x270 lib/usercopy.c:33
 instrument_copy_to_user include/linux/instrumented.h:121 [inline]
 _copy_to_user+0x1c9/0x270 lib/usercopy.c:33
 copy_to_user include/linux/uaccess.h:209 [inline]
 move_addr_to_user+0x3f6/0x600 net/socket.c:287
 ____sys_recvmsg+0x6a9/0xb00 net/socket.c:2635
 ___sys_recvmsg net/socket.c:2670 [inline]
 do_recvmmsg+0x16f4/0x2120 net/socket.c:2756
 __sys_recvmmsg+0x51c/0x6f0 net/socket.c:2843
 __do_compat_sys_recvmmsg_time32 net/compat.c:419 [inline]
 __se_compat_sys_recvmmsg_time32 net/compat.c:415 [inline]
 __ia32_compat_sys_recvmmsg_time32+0x16e/0x1d0 net/compat.c:415
 do_syscall_32_irqs_on arch/x86/entry/common.c:114 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:180
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:205
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:248
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was stored to memory at:
 sctp_inet6_skb_msgname+0x7fa/0xb40 net/sctp/ipv6.c:905
 sctp_recvmsg+0x9f2/0x1420 net/sctp/socket.c:2137
 inet_recvmsg+0x21c/0x6d0 net/ipv4/af_inet.c:850
 ____sys_recvmsg+0x590/0xb00
 ___sys_recvmsg net/socket.c:2670 [inline]
 do_recvmmsg+0x16f4/0x2120 net/socket.c:2756
 __sys_recvmmsg+0x51c/0x6f0 net/socket.c:2843
 __do_compat_sys_recvmmsg_time32 net/compat.c:419 [inline]
 __se_compat_sys_recvmmsg_time32 net/compat.c:415 [inline]
 __ia32_compat_sys_recvmmsg_time32+0x16e/0x1d0 net/compat.c:415
 do_syscall_32_irqs_on arch/x86/entry/common.c:114 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:180
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:205
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:248
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was stored to memory at:
 skb_copy_from_linear_data_offset include/linux/skbuff.h:3785 [inline]
 skb_copy_bits+0x2ec/0x10f0 net/core/skbuff.c:2331
 skb_copy+0x54e/0xb90 net/core/skbuff.c:1597
 sctp_make_reassembled_event+0xba8/0x1000 net/sctp/ulpqueue.c:351
 sctp_ulpq_retrieve_first net/sctp/ulpqueue.c:666 [inline]
 sctp_ulpq_partial_delivery+0x887/0xb90 net/sctp/ulpqueue.c:1060
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1715 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1195 [inline]
 sctp_do_sm+0x48ed/0x9b50 net/sctp/sm_sideeffect.c:1166
 sctp_assoc_bh_rcv+0xa15/0xdd0 net/sctp/associola.c:1054
 sctp_inq_push+0x31c/0x440 net/sctp/inqueue.c:80
 sctp_rcv+0x408d/0x4260 net/sctp/input.c:256
 sctp4_rcv+0x60/0x80 net/sctp/protocol.c:1154
 ip_protocol_deliver_rcu+0x752/0x10a0 net/ipv4/ip_input.c:204
 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ip_local_deliver+0x584/0x8c0 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:460 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:429 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ip_rcv+0x5a5/0x830 net/ipv4/ip_input.c:540
 __netif_receive_skb_one_core net/core/dev.c:5465 [inline]
 __netif_receive_skb+0x1ec/0x630 net/core/dev.c:5579
 process_backlog+0x54b/0xc10 net/core/dev.c:6455
 __napi_poll+0x14c/0xc00 net/core/dev.c:7023
 napi_poll net/core/dev.c:7090 [inline]
 net_rx_action+0x7e2/0x1820 net/core/dev.c:7177
 __do_softirq+0x1ee/0x7c5 kernel/softirq.c:558

Uninit was created at:
 kmalloc_large_node_hook mm/slub.c:1695 [inline]
 kmalloc_large_node+0x29c/0x2e0 mm/slub.c:4462
 __kmalloc_node_track_caller+0xbcf/0x1510 mm/slub.c:4960
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 __alloc_skb+0x545/0xf90 net/core/skbuff.c:426
 alloc_skb include/linux/skbuff.h:1126 [inline]
 sctp_packet_transmit+0x528/0x45a0 net/sctp/output.c:597
 sctp_outq_flush_transports net/sctp/outqueue.c:1163 [inline]
 sctp_outq_flush+0x17d9/0x5eb0 net/sctp/outqueue.c:1211
 sctp_outq_uncork+0x105/0x120 net/sctp/outqueue.c:758
 sctp_side_effects net/sctp/sm_sideeffect.c:1195 [inline]
 sctp_do_sm+0x946f/0x9b50 net/sctp/sm_sideeffect.c:1166
 sctp_assoc_bh_rcv+0xa15/0xdd0 net/sctp/associola.c:1054
 sctp_inq_push+0x31c/0x440 net/sctp/inqueue.c:80
 sctp_rcv+0x408d/0x4260 net/sctp/input.c:256
 sctp4_rcv+0x60/0x80 net/sctp/protocol.c:1154
 ip_protocol_deliver_rcu+0x752/0x10a0 net/ipv4/ip_input.c:204
 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ip_local_deliver+0x584/0x8c0 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:460 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:429 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ip_rcv+0x5a5/0x830 net/ipv4/ip_input.c:540
 __netif_receive_skb_one_core net/core/dev.c:5465 [inline]
 __netif_receive_skb+0x1ec/0x630 net/core/dev.c:5579
 process_backlog+0x54b/0xc10 net/core/dev.c:6455
 __napi_poll+0x14c/0xc00 net/core/dev.c:7023
 napi_poll net/core/dev.c:7090 [inline]
 net_rx_action+0x7e2/0x1820 net/core/dev.c:7177
 __do_softirq+0x1ee/0x7c5 kernel/softirq.c:558

Bytes 2-3 of 28 are uninitialized
Memory access of size 28 starts at ffff888125413a90
Data copied to user address 0000000020000080

CPU: 0 PID: 8655 Comm: syz-executor.4 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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