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BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:121 [inline]
BUG: KMSAN: kernel-infoleak in copyout+0xbc/0x100 lib/iov_iter.c:169
 instrument_copy_to_user include/linux/instrumented.h:121 [inline]
 copyout+0xbc/0x100 lib/iov_iter.c:169
 _copy_to_iter+0x4ec/0x1fd0 lib/iov_iter.c:523
 copy_to_iter include/linux/uio.h:181 [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
 skb_copy_datagram_msg include/linux/skbuff.h:3934 [inline]
 nr_recvmsg+0x406/0x6d0 net/netrom/af_netrom.c:1181
 sock_recvmsg_nosec net/socket.c:1017 [inline]
 sock_recvmsg net/socket.c:1038 [inline]
 sock_read_iter+0x48e/0x5d0 net/socket.c:1116
 do_iter_read+0x642/0x1300 fs/read_write.c:796
 vfs_readv fs/read_write.c:916 [inline]
 do_readv+0x35c/0x760 fs/read_write.c:953
 __do_sys_readv fs/read_write.c:1044 [inline]
 __se_sys_readv fs/read_write.c:1041 [inline]
 __ia32_sys_readv+0x95/0xe0 fs/read_write.c:1041
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Uninit was stored to memory at:
 skb_copy_from_linear_data include/linux/skbuff.h:4055 [inline]
 nr_loopback_queue+0x10d/0x310 net/netrom/nr_loopback.c:35
 nr_route_frame+0x1f1/0xfc0 net/netrom/nr_route.c:776
 nr_transmit_buffer+0x187/0x2a0 net/netrom/nr_out.c:209
 nr_write_internal+0x81e/0xe30 net/netrom/nr_subr.c:205
 nr_establish_data_link+0x4f/0x80 net/netrom/nr_out.c:227
 nr_connect+0xb9b/0x1520 net/netrom/af_netrom.c:718
 __sys_connect_file net/socket.c:2001 [inline]
 __sys_connect+0x6bc/0x760 net/socket.c:2018
 __do_sys_connect net/socket.c:2028 [inline]
 __se_sys_connect net/socket.c:2025 [inline]
 __ia32_sys_connect+0x90/0xe0 net/socket.c:2025
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

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:1278 [inline]
 nr_write_internal+0x15f/0xe30 net/netrom/nr_subr.c:144
 nr_establish_data_link+0x4f/0x80 net/netrom/nr_out.c:227
 nr_connect+0xb9b/0x1520 net/netrom/af_netrom.c:718
 __sys_connect_file net/socket.c:2001 [inline]
 __sys_connect+0x6bc/0x760 net/socket.c:2018
 __do_sys_connect net/socket.c:2028 [inline]
 __se_sys_connect net/socket.c:2025 [inline]
 __ia32_sys_connect+0x90/0xe0 net/socket.c:2025
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Bytes 37-124 of 125 are uninitialized
Memory access of size 125 starts at ffff8880a861b400
Data copied to user address 0000000020000240

CPU: 0 PID: 9748 Comm: syz-executor.1 Not tainted 6.3.0-syzkaller-g81af97bdef5e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
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