syzbot

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BUG: KMSAN: uninit-value in do_update_region+0x6ef/0xb80 drivers/tty/vt/vt.c:665
CPU: 1 PID: 19349 Comm: getty Not tainted 5.6.0-rc2-syzkaller #0
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+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 do_update_region+0x6ef/0xb80 drivers/tty/vt/vt.c:665
 csi_J+0xe5c/0x1060 drivers/tty/vt/vt.c:1531
 do_con_trol drivers/tty/vt/vt.c:2367 [inline]
 do_con_write+0x8cbf/0x13160 drivers/tty/vt/vt.c:2797
 con_write+0x8e/0xe0 drivers/tty/vt/vt.c:3135
 process_output_block drivers/tty/n_tty.c:595 [inline]
 n_tty_write+0x13c7/0x1d40 drivers/tty/n_tty.c:2333
 do_tty_write drivers/tty/tty_io.c:962 [inline]
 tty_write+0xc06/0x12e0 drivers/tty/tty_io.c:1046
 __vfs_write+0x1a9/0xca0 fs/read_write.c:494
 vfs_write+0x44a/0x8f0 fs/read_write.c:558
 ksys_write+0x267/0x450 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write+0x92/0xb0 fs/read_write.c:620
 __x64_sys_write+0x4a/0x70 fs/read_write.c:620
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f83982c0370
Code: 73 01 c3 48 8b 0d c8 4a 2b 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 83 3d 85 a2 2b 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 0e 8a 01 00 48 89 04 24
RSP: 002b:00007ffd9afc2a38 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f83982c0370
RDX: 0000000000000009 RSI: 0000000000405be5 RDI: 0000000000000001
RBP: 00007f83989956a8 R08: 00007ffd9afc3290 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000405be5
R13: 00007ffd9afc5f0f R14: 00007ffd9afc5f12 R15: 0000000000000000

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slab index 1824 out of bounds (524) for stack id 07200720
WARNING: CPU: 1 PID: 19349 at lib/stackdepot.c:230 stack_depot_fetch+0x29/0x70 lib/stackdepot.c:229