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BUG: KMSAN: kernel-infoleak in copyout+0x16b/0x1f0 lib/iov_iter.c:144
CPU: 0 PID: 12321 Comm: syz-executor.4 Not tainted 5.1.0-rc7+ #5
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+0x130/0x2a0 mm/kmsan/kmsan.c:619
 kmsan_internal_check_memory+0x544/0xa80 mm/kmsan/kmsan.c:684
 kmsan_copy_to_user+0xa9/0xb0 mm/kmsan/kmsan_hooks.c:492
 copyout+0x16b/0x1f0 lib/iov_iter.c:144
 _copy_to_iter+0x36a/0x2690 lib/iov_iter.c:615
 copy_to_iter include/linux/uio.h:150 [inline]
 simple_copy_to_iter+0x92/0xb0 net/core/datagram.c:516
 __skb_datagram_iter+0x256/0xe70 net/core/datagram.c:424
 skb_copy_datagram_iter+0x29c/0x2b0 net/core/datagram.c:530
 skb_copy_datagram_msg include/linux/skbuff.h:3398 [inline]
 netlink_recvmsg+0x68c/0x18e0 net/netlink/af_netlink.c:1984
 sock_recvmsg_nosec net/socket.c:881 [inline]
 sock_recvmsg+0x1d1/0x230 net/socket.c:888
 ___sys_recvmsg+0x485/0x1320 net/socket.c:2422
 do_recvmmsg+0x5f6/0x10b0 net/socket.c:2535
 __sys_recvmmsg net/socket.c:2614 [inline]
 __do_sys_recvmmsg net/socket.c:2637 [inline]
 __se_sys_recvmmsg+0x1d1/0x350 net/socket.c:2630
 __x64_sys_recvmmsg+0x62/0x80 net/socket.c:2630
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x458da9
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fdcd39e0c78 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000458da9
RDX: 0000000000000004 RSI: 0000000020001680 RDI: 0000000000000005
RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdcd39e16d4
R13: 00000000004c5d13 R14: 00000000004da298 R15: 00000000ffffffff

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:159
 kmsan_kmalloc+0xa4/0x130 mm/kmsan/kmsan_hooks.c:174
 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:183
 slab_post_alloc_hook mm/slab.h:442 [inline]
 slab_alloc_node mm/slub.c:2771 [inline]
 __kmalloc_node_track_caller+0xcba/0xf30 mm/slub.c:4399
 __kmalloc_reserve net/core/skbuff.c:140 [inline]
 __alloc_skb+0x306/0xa10 net/core/skbuff.c:208
 alloc_skb include/linux/skbuff.h:1059 [inline]
 netlink_dump+0x44b/0x1ab0 net/netlink/af_netlink.c:2233
 __netlink_dump_start+0xa3a/0xb30 net/netlink/af_netlink.c:2361
 netlink_dump_start include/linux/netlink.h:226 [inline]
 inet_diag_handler_cmd+0x7ad/0x850 net/ipv4/inet_diag.c:1180
 sock_diag_rcv_msg+0x211/0x610 net/core/sock_diag.c:255
 netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2486
 sock_diag_rcv+0x63/0x80 net/core/sock_diag.c:274
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1337
 netlink_sendmsg+0x127e/0x12f0 net/netlink/af_netlink.c:1926
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:661 [inline]
 sock_write_iter+0x3f3/0x4e0 net/socket.c:988
 do_iter_readv_writev+0x9b3/0xbe0 include/linux/fs.h:1860
 do_iter_write+0x304/0xdc0 fs/read_write.c:957
 vfs_writev fs/read_write.c:1002 [inline]
 do_writev+0x3ba/0x8e0 fs/read_write.c:1037
 __do_sys_writev fs/read_write.c:1110 [inline]
 __se_sys_writev+0x9b/0xb0 fs/read_write.c:1107
 __x64_sys_writev+0x4a/0x70 fs/read_write.c:1107
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Bytes 68-71 of 166 are uninitialized
Memory access of size 166 starts at ffff8880ae365000
Data copied to user address 0000000020000380
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