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BUG: KASAN: user-memory-access in memmove include/linux/string.h:363 [inline]
BUG: KASAN: user-memory-access in scr_memmovew include/linux/vt_buffer.h:68 [inline]
BUG: KASAN: user-memory-access in insert_char+0x1f9/0x440 drivers/tty/vt/vt.c:839
Read of size 2 at addr 000000010000000c by task syz-executor.0/9744

CPU: 0 PID: 9744 Comm: syz-executor.0 Not tainted 4.19.114-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+0x188/0x20d lib/dump_stack.c:118
 kasan_report_error mm/kasan/report.c:352 [inline]
 kasan_report mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x194/0x2b9 mm/kasan/report.c:396
 memmove+0x20/0x50 mm/kasan/kasan.c:293
 memmove include/linux/string.h:363 [inline]
 scr_memmovew include/linux/vt_buffer.h:68 [inline]
 insert_char+0x1f9/0x440 drivers/tty/vt/vt.c:839
 csi_at drivers/tty/vt/vt.c:1989 [inline]
 do_con_trol+0x399e/0x5c00 drivers/tty/vt/vt.c:2436
 do_con_write.part.0+0xf55/0x1db0 drivers/tty/vt/vt.c:2797
 do_con_write drivers/tty/vt/vt.c:2565 [inline]
 con_write+0x41/0xe0 drivers/tty/vt/vt.c:3132
 process_output_block drivers/tty/n_tty.c:593 [inline]
 n_tty_write+0x3ee/0x1080 drivers/tty/n_tty.c:2331
 do_tty_write drivers/tty/tty_io.c:960 [inline]
 tty_write+0x452/0x790 drivers/tty/tty_io.c:1044
 __vfs_write+0xf7/0x760 fs/read_write.c:485
 vfs_write+0x206/0x550 fs/read_write.c:549
 ksys_write+0x12b/0x2a0 fs/read_write.c:599
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c889
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f13f4183c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f13f41846d4 RCX: 000000000045c889
RDX: 00000000000000e7 RSI: 00000000200000c0 RDI: 0000000000000006
RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000cdc R14: 00000000004cf042 R15: 000000000076bf0c
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