mmap: syz-executor6 (5807) uses deprecated remap_file_pages() syscall. See Documentation/vm/remap_file_pages.txt.
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BUG: KMSAN: uninit-value in copyout lib/iov_iter.c:140 [inline]
BUG: KMSAN: uninit-value in _copy_to_iter+0x46d/0x28f0 lib/iov_iter.c:571
CPU: 0 PID: 5814 Comm: syz-executor2 Not tainted 4.16.0+ #84
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 kmsan_internal_check_memory+0x135/0x1e0 mm/kmsan/kmsan.c:1157
 kmsan_copy_to_user+0x69/0x160 mm/kmsan/kmsan.c:1199
 copyout lib/iov_iter.c:140 [inline]
 _copy_to_iter+0x46d/0x28f0 lib/iov_iter.c:571
 copy_to_iter include/linux/uio.h:106 [inline]
 skb_copy_datagram_iter+0x443/0xf70 net/core/datagram.c:431
 skb_copy_datagram_msg include/linux/skbuff.h:3264 [inline]
 packet_recvmsg+0x757/0x1cc0 net/packet/af_packet.c:3341
 sock_recvmsg_nosec net/socket.c:803 [inline]
 sock_recvmsg+0x1d0/0x230 net/socket.c:810
 ___sys_recvmsg+0x3fb/0x810 net/socket.c:2205
 __sys_recvmsg net/socket.c:2250 [inline]
 SYSC_recvmsg+0x298/0x3c0 net/socket.c:2262
 SyS_recvmsg+0x54/0x80 net/socket.c:2257
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x455329
RSP: 002b:00007f39c3f2ec68 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007f39c3f2f6d4 RCX: 0000000000455329
RDX: 0000000000000000 RSI: 0000000020000700 RDI: 0000000000000015
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000496 R14: 00000000006f9eb0 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:293 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684
 kmsan_memcpy_origins+0x11d/0x170 mm/kmsan/kmsan.c:526
 __msan_memcpy+0x19f/0x1f0 mm/kmsan/kmsan_instr.c:470
 pskb_expand_head+0x3a6/0x1a70 net/core/skbuff.c:1467
 skb_unclone include/linux/skbuff.h:1437 [inline]
 skb_copy_ubufs+0x375/0x2640 net/core/skbuff.c:1181
 skb_orphan_frags_rx include/linux/skbuff.h:2565 [inline]
 dev_queue_xmit_nit+0x1180/0x11e0 net/core/dev.c:1990
 xmit_one net/core/dev.c:3022 [inline]
 dev_hard_start_xmit+0x27c/0xc70 net/core/dev.c:3042
 __dev_queue_xmit+0x22d9/0x2b60 net/core/dev.c:3557
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3590
 neigh_hh_output include/net/neighbour.h:472 [inline]
 neigh_output include/net/neighbour.h:480 [inline]
 ip_finish_output2+0x1198/0x1380 net/ipv4/ip_output.c:229
 ip_finish_output+0xcb0/0xff0 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:277 [inline]
 ip_output+0x502/0x5c0 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:443 [inline]
 ip_local_out net/ipv4/ip_output.c:124 [inline]
 ip_queue_xmit+0x1fae/0x21c0 net/ipv4/ip_output.c:504
 tcp_transmit_skb+0x38be/0x51f0 net/ipv4/tcp_output.c:1176
 tcp_write_xmit+0x4311/0xb920 net/ipv4/tcp_output.c:2394
 __tcp_push_pending_frames+0x124/0x3f0 net/ipv4/tcp_output.c:2567
 tcp_push+0x8b6/0x9c0 net/ipv4/tcp.c:726
 tcp_sendmsg_locked+0x5445/0x6d20 net/ipv4/tcp.c:1426
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1463
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 sock_write_iter+0x3b9/0x470 net/socket.c:909
 call_write_iter include/linux/fs.h:1782 [inline]
 new_sync_write fs/read_write.c:469 [inline]
 __vfs_write+0x719/0x910 fs/read_write.c:482
 vfs_write+0x463/0x8d0 fs/read_write.c:544
 SYSC_write+0x172/0x360 fs/read_write.c:589
 SyS_write+0x55/0x80 fs/read_write.c:581
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
 alloc_skb_fclone include/linux/skbuff.h:1026 [inline]
 sk_stream_alloc_skb+0x17c/0xcf0 net/ipv4/tcp.c:866
 tcp_sendmsg_locked+0x2cc0/0x6d20 net/ipv4/tcp.c:1301
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1463
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Bytes 18-19 of 66 are uninitialized
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