=====================================================
BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:121 [inline]
BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:156 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x6f8/0x2550 lib/iov_iter.c:670
 instrument_copy_to_user include/linux/instrumented.h:121 [inline]
 copyout lib/iov_iter.c:156 [inline]
 _copy_to_iter+0x6f8/0x2550 lib/iov_iter.c:670
 copy_to_iter include/linux/uio.h:155 [inline]
 simple_copy_to_iter+0xf3/0x140 net/core/datagram.c:519
 __skb_datagram_iter+0x2d5/0x11b0 net/core/datagram.c:425
 skb_copy_datagram_iter+0xdc/0x270 net/core/datagram.c:533
 skb_copy_datagram_msg include/linux/skbuff.h:3657 [inline]
 nr_recvmsg+0x3f6/0x800 net/netrom/af_netrom.c:1175
 ____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 include/linux/skbuff.h:3778 [inline]
 nr_loopback_queue+0x1c4/0x400 net/netrom/nr_loopback.c:35
 nr_route_frame+0x292/0x1470 net/netrom/nr_route.c:776
 nr_transmit_buffer+0x237/0x370 net/netrom/nr_out.c:209
 nr_write_internal+0xc70/0x1050 net/netrom/nr_subr.c:205
 nr_establish_data_link+0x8b/0x100 net/netrom/nr_out.c:227
 nr_connect+0x14ed/0x1e80 net/netrom/af_netrom.c:713
 __sys_connect_file net/socket.c:1896 [inline]
 __sys_connect+0x7bb/0x830 net/socket.c:1913
 __do_sys_connect net/socket.c:1923 [inline]
 __se_sys_connect net/socket.c:1920 [inline]
 __ia32_sys_connect+0xdb/0x130 net/socket.c:1920
 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 created at:
 slab_post_alloc_hook mm/slab.h:524 [inline]
 slab_alloc_node mm/slub.c:3251 [inline]
 __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974
 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]
 nr_write_internal+0x184/0x1050 net/netrom/nr_subr.c:144
 nr_establish_data_link+0x8b/0x100 net/netrom/nr_out.c:227
 nr_connect+0x14ed/0x1e80 net/netrom/af_netrom.c:713
 __sys_connect_file net/socket.c:1896 [inline]
 __sys_connect+0x7bb/0x830 net/socket.c:1913
 __do_sys_connect net/socket.c:1923 [inline]
 __se_sys_connect net/socket.c:1920 [inline]
 __ia32_sys_connect+0xdb/0x130 net/socket.c:1920
 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

Bytes 37-191 of 192 are uninitialized
Memory access of size 192 starts at ffff888087e10e00
Data copied to user address 0000000020002c80

CPU: 1 PID: 17551 Comm: syz-executor.1 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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