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BUG: KMSAN: kernel-infoleak in copyout+0x16b/0x1f0 /lib/iov_iter.c:145
CPU: 0 PID: 12547 Comm: syz-executor694 Not tainted 5.2.0+ #15
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack /lib/dump_stack.c:77 [inline]
 dump_stack+0x191/0x1f0 /lib/dump_stack.c:113
 kmsan_report+0x162/0x2d0 /mm/kmsan/kmsan_report.c:109
 kmsan_internal_check_memory+0x544/0xa80 /mm/kmsan/kmsan.c:522
 kmsan_copy_to_user+0xa9/0xb0 /mm/kmsan/kmsan_hooks.c:493
 copyout+0x16b/0x1f0 /lib/iov_iter.c:145
 _copy_to_iter+0x366/0x26e0 /lib/iov_iter.c:616
 copy_to_iter /./include/linux/uio.h:146 [inline]
 simple_copy_to_iter+0x92/0xb0 /net/core/datagram.c:515
 __skb_datagram_iter+0x256/0xe60 /net/core/datagram.c:423
 skb_copy_datagram_iter+0x29c/0x2b0 /net/core/datagram.c:529
 skb_copy_datagram_msg /./include/linux/skbuff.h:3405 [inline]
 netlink_recvmsg+0x68c/0x18e0 /net/netlink/af_netlink.c:1980
 sock_recvmsg_nosec /net/socket.c:877 [inline]
 sock_recvmsg+0x2df/0x2f0 /net/socket.c:894
 ___sys_recvmsg+0x3d9/0x1140 /net/socket.c:2448
 do_recvmmsg+0x5f6/0x10a0 /net/socket.c:2561
 __sys_recvmmsg /net/socket.c:2640 [inline]
 __do_sys_recvmmsg /net/socket.c:2663 [inline]
 __se_sys_recvmmsg+0x1d1/0x350 /net/socket.c:2656
 __x64_sys_recvmmsg+0x62/0x80 /net/socket.c:2656
 do_syscall_64+0xbc/0xf0 /arch/x86/entry/common.c:302
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x4459a9
Code: e8 bc b7 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f6c76f13d98 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 00000000004459a9
RDX: 0000000000000001 RSI: 0000000020001680 RDI: 0000000000000004
RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 00000000006dac3c
R13: 06e0ff807aed8402 R14: 568c0dfdea4b0009 R15: 0d19001400000048

Uninit was created at:
 kmsan_save_stack_with_flags /mm/kmsan/kmsan.c:187 [inline]
 kmsan_internal_poison_shadow+0x53/0xa0 /mm/kmsan/kmsan.c:146
 kmsan_slab_alloc+0xaa/0x120 /mm/kmsan/kmsan_hooks.c:175
 slab_alloc_node /mm/slub.c:2771 [inline]
 __kmalloc_node_track_caller+0xc8f/0xf10 /mm/slub.c:4389
 __kmalloc_reserve /net/core/skbuff.c:138 [inline]
 __alloc_skb+0x306/0xa10 /net/core/skbuff.c:206
 alloc_skb /./include/linux/skbuff.h:1055 [inline]
 netlink_dump+0x44b/0x1ab0 /net/netlink/af_netlink.c:2229
 __netlink_dump_start+0xa3a/0xb30 /net/netlink/af_netlink.c:2357
 netlink_dump_start /./include/linux/netlink.h:226 [inline]
 inet_diag_handler_cmd+0x7ad/0x850 /net/ipv4/inet_diag.c:1176
 sock_diag_rcv_msg+0x211/0x610 /net/core/sock_diag.c:255
 netlink_rcv_skb+0x431/0x620 /net/netlink/af_netlink.c:2482
 sock_diag_rcv+0x63/0x80 /net/core/sock_diag.c:274
 netlink_unicast_kernel /net/netlink/af_netlink.c:1307 [inline]
 netlink_unicast+0xf3e/0x1020 /net/netlink/af_netlink.c:1333
 netlink_sendmsg+0x127e/0x12f0 /net/netlink/af_netlink.c:1922
 sock_sendmsg_nosec /net/socket.c:646 [inline]
 sock_sendmsg /net/socket.c:665 [inline]
 sock_write_iter+0x552/0x5a0 /net/socket.c:994
 do_iter_readv_writev+0xa16/0xc30 /./include/linux/fs.h:1866
 do_iter_write+0x304/0xdc0 /fs/read_write.c:970
 vfs_writev /fs/read_write.c:1015 [inline]
 do_writev+0x437/0x910 /fs/read_write.c:1058
 __do_sys_writev /fs/read_write.c:1131 [inline]
 __se_sys_writev+0x9b/0xb0 /fs/read_write.c:1128
 __x64_sys_writev+0x4a/0x70 /fs/read_write.c:1128
 do_syscall_64+0xbc/0xf0 /arch/x86/entry/common.c:302
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Bytes 68-71 of 166 are uninitialized
Memory access of size 166 starts at ffff8880baf22000
Data copied to user address 0000000020000380
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