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BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:140 [inline]
BUG: KMSAN: kernel-infoleak in copy_page_to_iter_iovec lib/iov_iter.c:212 [inline]
BUG: KMSAN: kernel-infoleak in copy_page_to_iter+0x754/0x1b70 lib/iov_iter.c:716
CPU: 0 PID: 13963 Comm: blkid Not tainted 4.17.0+ #9
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+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1125
 kmsan_internal_check_memory+0x17e/0x1f0 mm/kmsan/kmsan.c:1238
 kmsan_copy_to_user+0x7a/0x160 mm/kmsan/kmsan.c:1261
 copyout lib/iov_iter.c:140 [inline]
 copy_page_to_iter_iovec lib/iov_iter.c:212 [inline]
 copy_page_to_iter+0x754/0x1b70 lib/iov_iter.c:716
 generic_file_buffered_read mm/filemap.c:2185 [inline]
 generic_file_read_iter+0x2ef8/0x44d0 mm/filemap.c:2362
 blkdev_read_iter+0x20d/0x280 fs/block_dev.c:1930
 call_read_iter include/linux/fs.h:1778 [inline]
 new_sync_read fs/read_write.c:406 [inline]
 __vfs_read+0x775/0x9d0 fs/read_write.c:418
 vfs_read+0x36c/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 fs/read_write.c:586 [inline]
 __x64_sys_read+0x1bf/0x3e0 fs/read_write.c:586
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f6923b92310
RSP: 002b:00007ffe0902d648 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6923b92310
RDX: 0000000000000100 RSI: 000000000233ddf8 RDI: 0000000000000003
RBP: 000000000233ddd0 R08: 0000000000000028 R09: 0000000001680000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000233d030
R13: 0000000000000100 R14: 000000000233d080 R15: 000000000233dde8

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:282 [inline]
 kmsan_alloc_meta_for_pages+0x161/0x3a0 mm/kmsan/kmsan.c:819
 kmsan_alloc_page+0x82/0xe0 mm/kmsan/kmsan.c:889
 __alloc_pages_nodemask+0xf7b/0x5cc0 mm/page_alloc.c:4402
 alloc_pages_current+0x6b1/0x970 mm/mempolicy.c:2093
 alloc_pages include/linux/gfp.h:494 [inline]
 __page_cache_alloc+0x95/0x320 mm/filemap.c:946
 pagecache_get_page+0x52b/0x1450 mm/filemap.c:1577
 grab_cache_page_write_begin+0x10d/0x190 mm/filemap.c:3089
 block_write_begin+0xf9/0x3a0 fs/buffer.c:2068
 blkdev_write_begin+0xf5/0x110 fs/block_dev.c:584
 generic_perform_write+0x438/0x9d0 mm/filemap.c:3139
 __generic_file_write_iter+0x43b/0xa10 mm/filemap.c:3264
 blkdev_write_iter+0x3a8/0x5f0 fs/block_dev.c:1910
 call_write_iter include/linux/fs.h:1784 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x808/0x9f0 fs/read_write.c:487
 vfs_write+0x467/0x8c0 fs/read_write.c:549
 ksys_write fs/read_write.c:598 [inline]
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x1bf/0x3e0 fs/read_write.c:607
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Bytes 216-255 of 256 are uninitialized
Memory access starts at ffff88011cdb2000
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