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BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in _inline_copy_to_user include/linux/uaccess.h:196 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 _inline_copy_to_user include/linux/uaccess.h:196 [inline]
 _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:225 [inline]
 move_addr_to_user+0x29c/0x410 net/socket.c:293
 ____sys_recvmsg+0x232/0x610 net/socket.c:2793
 ___sys_recvmsg+0x20b/0x850 net/socket.c:2828
 __sys_recvmsg net/socket.c:2861 [inline]
 __do_sys_recvmsg net/socket.c:2867 [inline]
 __se_sys_recvmsg net/socket.c:2864 [inline]
 __x64_sys_recvmsg+0x20e/0x3d0 net/socket.c:2864
 x64_sys_call+0x11ff/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:48
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 skb_copy_from_linear_data_offset include/linux/skbuff.h:4254 [inline]
 nr_recvmsg+0x59b/0x790 net/netrom/af_netrom.c:1196
 sock_recvmsg_nosec net/socket.c:1017 [inline]
 sock_recvmsg+0x2dc/0x390 net/socket.c:1039
 ____sys_recvmsg+0x193/0x610 net/socket.c:2786
 ___sys_recvmsg+0x20b/0x850 net/socket.c:2828
 __sys_recvmsg net/socket.c:2861 [inline]
 __do_sys_recvmsg net/socket.c:2867 [inline]
 __se_sys_recvmsg net/socket.c:2864 [inline]
 __x64_sys_recvmsg+0x20e/0x3d0 net/socket.c:2864
 x64_sys_call+0x11ff/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:48
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4154 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_node_noprof+0x818/0xf00 mm/slub.c:4249
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670
 alloc_skb include/linux/skbuff.h:1336 [inline]
 nr_loopback_queue+0x5f/0x400 net/netrom/nr_loopback.c:34
 nr_route_frame+0x264/0xff0 net/netrom/nr_route.c:777
 nr_transmit_buffer+0x1ab/0x2f0 net/netrom/nr_out.c:209
 nr_send_iframe net/netrom/nr_out.c:94 [inline]
 nr_kick+0x5b0/0x940 net/netrom/nr_out.c:166
 nr_output+0x7a0/0x7d0 net/netrom/nr_out.c:72
 nr_sendmsg+0xb10/0xe30 net/netrom/af_netrom.c:1143
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x333/0x3d0 net/socket.c:727
 sock_write_iter+0x318/0x390 net/socket.c:1131
 do_iter_readv_writev+0x947/0xba0 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __x64_sys_writev+0x99/0xf0 fs/read_write.c:1168
 x64_sys_call+0x269a/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Bytes 2-8 of 16 are uninitialized
Memory access of size 16 starts at ffff888041f87b58
Data copied to user address 00002000000006c0

CPU: 0 UID: 0 PID: 9521 Comm: syz.0.782 Not tainted 6.16.0-rc4-syzkaller #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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