KMSAN: kernel-infoleak in copy_page_to_itermodprobe (3512) used greatest stack depth: 56216 bytes left
tput (3519) used greatest stack depth: 54112 bytes left
audit: type=1800 audit(1543578004.907:2): pid=3524 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mountkernfs.sh" dev="sda1" ino=2430 res=0
audit: type=1800 audit(1543578006.157:3): pid=3524 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="udev" dev="sda1" ino=2424 res=0
==================================================================
BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:143 [inline]
BUG: KMSAN: kernel-infoleak in copy_page_to_iter_iovec lib/iov_iter.c:215 [inline]
BUG: KMSAN: kernel-infoleak in copy_page_to_iter+0x841/0x1cc0 lib/iov_iter.c:853
CPU: 1 PID: 3913 Comm: blkid Not tainted 4.20.0-rc3+ #98
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+0x32d/0x480 lib/dump_stack.c:113
 kmsan_report+0x12c/0x290 mm/kmsan/kmsan.c:682
 kmsan_internal_check_memory+0x9ce/0xa50 mm/kmsan/kmsan.c:768
 kmsan_copy_to_user+0x78/0xd0 mm/kmsan/kmsan_hooks.c:634
 copyout lib/iov_iter.c:143 [inline]
 copy_page_to_iter_iovec lib/iov_iter.c:215 [inline]
 copy_page_to_iter+0x841/0x1cc0 lib/iov_iter.c:853
 generic_file_buffered_read mm/filemap.c:2113 [inline]
 generic_file_read_iter+0x3905/0x4ff0 mm/filemap.c:2290
 blkdev_read_iter+0x20d/0x270 fs/block_dev.c:1936
 call_read_iter include/linux/fs.h:1851 [inline]
 new_sync_read fs/read_write.c:406 [inline]
 __vfs_read+0x874/0xb00 fs/read_write.c:418
 vfs_read+0x380/0x6b0 fs/read_write.c:452
 ksys_read fs/read_write.c:578 [inline]
 __do_sys_read fs/read_write.c:588 [inline]
 __se_sys_read+0x17a/0x370 fs/read_write.c:586
 __x64_sys_read+0x4a/0x70 fs/read_write.c:586
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x7f23f431b310
Code: 73 01 c3 48 8b 0d 28 4b 2b 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 83 3d e5 a2 2b 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 6e 8a 01 00 48 89 04 24
RSP: 002b:00007fff5900ee88 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000003e7fff0000 RCX: 00007f23f431b310
RDX: 0000000000000040 RSI: 0000000001d84c58 RDI: 0000000000000003
RBP: 0000000001d84c30 R08: 0000000000000068 R09: 0101010101010101
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000001d84030
R13: 0000000000000040 R14: 0000000001d84080 R15: 0000000001d84c48

Uninit was created at:
 kmsan_save_stack_with_flags+0x51/0x100 mm/kmsan/kmsan.c:245
 kmsan_internal_alloc_meta_for_pages+0x10e/0x640 mm/kmsan/kmsan_hooks.c:102
 kmsan_alloc_page+0x77/0xc0 mm/kmsan/kmsan_hooks.c:402
 __alloc_pages_nodemask+0x175b/0x63e0 mm/page_alloc.c:4416
 alloc_pages_current+0x55d/0x7d0 mm/mempolicy.c:2080
 alloc_pages include/linux/gfp.h:511 [inline]
 __page_cache_alloc+0xdb/0x4a0 mm/filemap.c:925
 __do_page_cache_readahead+0x46e/0x9a0 mm/readahead.c:196
 force_page_cache_readahead mm/readahead.c:243 [inline]
 page_cache_sync_readahead+0x914/0xa00 mm/readahead.c:524
 generic_file_buffered_read mm/filemap.c:2020 [inline]
 generic_file_read_iter+0x1132/0x4ff0 mm/filemap.c:2290
 blkdev_read_iter+0x20d/0x270 fs/block_dev.c:1936
 call_read_iter include/linux/fs.h:1851 [inline]
 new_sync_read fs/read_write.c:406 [inline]
 __vfs_read+0x874/0xb00 fs/read_write.c:418
 vfs_read+0x380/0x6b0 fs/read_write.c:452
 ksys_read fs/read_write.c:578 [inline]
 __do_sys_read fs/read_write.c:588 [inline]
 __se_sys_read+0x17a/0x370 fs/read_write.c:586
 __x64_sys_read+0x4a/0x70 fs/read_write.c:586
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Bytes 0-63 of 64 are uninitialized
Memory access of size 64 starts at ffff88812bf02000
Data copied to user address 0000000001d84c58
==================================================================