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BUG: KMSAN: uninit-value in copy_to_user include/linux/uaccess.h:184 [inline]
BUG: KMSAN: uninit-value in vcs_read+0x18ba/0x1cc0 drivers/tty/vt/vc_screen.c:352
CPU: 0 PID: 7878 Comm: syz-executor6 Not tainted 4.16.0+ #81
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+0x164/0x1d0 mm/kmsan/kmsan.c:1176
 kmsan_copy_to_user+0x69/0x160 mm/kmsan/kmsan.c:1199
 copy_to_user include/linux/uaccess.h:184 [inline]
 vcs_read+0x18ba/0x1cc0 drivers/tty/vt/vc_screen.c:352
 do_loop_readv_writev fs/read_write.c:673 [inline]
 do_iter_read+0x880/0xd70 fs/read_write.c:897
 vfs_readv fs/read_write.c:959 [inline]
 do_readv+0x295/0x5f0 fs/read_write.c:992
 SYSC_readv+0x9b/0xb0 fs/read_write.c:1079
 SyS_readv+0x56/0x80 fs/read_write.c:1076
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x455259
RSP: 002b:00007fb196199c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000013
RAX: ffffffffffffffda RBX: 00007fb19619a6d4 RCX: 0000000000455259
RDX: 0000000000000001 RSI: 0000000020266000 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000048c R14: 00000000006f9dc0 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_alloc_meta_for_pages+0x161/0x3a0 mm/kmsan/kmsan.c:814
 kmsan_alloc_page+0x82/0xe0 mm/kmsan/kmsan.c:868
 __alloc_pages_nodemask+0xf5b/0x5dc0 mm/page_alloc.c:4283
 alloc_pages_current+0x6b5/0x970 mm/mempolicy.c:2055
 alloc_pages include/linux/gfp.h:494 [inline]
 __get_free_pages+0x2d/0xc0 mm/page_alloc.c:4304
 vcs_read+0x113/0x1cc0 drivers/tty/vt/vc_screen.c:210
 do_loop_readv_writev fs/read_write.c:673 [inline]
 do_iter_read+0x880/0xd70 fs/read_write.c:897
 vfs_readv fs/read_write.c:959 [inline]
 do_readv+0x295/0x5f0 fs/read_write.c:992
 SYSC_readv+0x9b/0xb0 fs/read_write.c:1079
 SyS_readv+0x56/0x80 fs/read_write.c:1076
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Bytes 4-108 of 109 are uninitialized
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