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BUG: KASAN: wild-memory-access in memmove include/linux/string.h:396 [inline]
BUG: KASAN: wild-memory-access in scr_memmovew include/linux/vt_buffer.h:68 [inline]
BUG: KASAN: wild-memory-access in insert_char+0x1f9/0x3f0 drivers/tty/vt/vt.c:840
Read of size 398 at addr 00000000fffffe80 by task syz-executor.5/9112

CPU: 0 PID: 9112 Comm: syz-executor.5 Not tainted 5.7.0-rc3-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.cold+0x5/0x4d mm/kasan/report.c:515
 kasan_report+0x33/0x50 mm/kasan/common.c:625
 check_memory_region_inline mm/kasan/generic.c:187 [inline]
 check_memory_region+0x141/0x190 mm/kasan/generic.c:193
 memmove+0x20/0x60 mm/kasan/common.c:95
 memmove include/linux/string.h:396 [inline]
 scr_memmovew include/linux/vt_buffer.h:68 [inline]
 insert_char+0x1f9/0x3f0 drivers/tty/vt/vt.c:840
 csi_at drivers/tty/vt/vt.c:1987 [inline]
 do_con_trol+0x3e56/0x5d10 drivers/tty/vt/vt.c:2454
 do_con_write.part.0+0xf34/0x1dc0 drivers/tty/vt/vt.c:2818
 do_con_write drivers/tty/vt/vt.c:2588 [inline]
 con_write+0x41/0xe0 drivers/tty/vt/vt.c:3154
 process_output_block drivers/tty/n_tty.c:595 [inline]
 n_tty_write+0x3f0/0xf90 drivers/tty/n_tty.c:2333
 do_tty_write drivers/tty/tty_io.c:962 [inline]
 tty_write+0x495/0x800 drivers/tty/tty_io.c:1046
 __vfs_write+0x76/0x100 fs/read_write.c:495
 vfs_write+0x268/0x5d0 fs/read_write.c:559
 ksys_write+0x12d/0x250 fs/read_write.c:612
 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
 do_fast_syscall_32+0x270/0xe90 arch/x86/entry/common.c:396
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
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