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BUG: KASAN: global-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:655 [inline]
BUG: KASAN: global-out-of-bounds in bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline]
BUG: KASAN: global-out-of-bounds in bit_putcs+0xbb6/0xd20 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffffffff88966020 by task syz-executor.3/14991

CPU: 1 PID: 14991 Comm: syz-executor.3 Not tainted 5.8.0-rc4-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+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x436 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 __fb_pad_aligned_buffer include/linux/fb.h:655 [inline]
 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline]
 bit_putcs+0xbb6/0xd20 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x33c/0x3f0 drivers/video/fbdev/core/fbcon.c:1362
 do_update_region+0x2d0/0x630 drivers/tty/vt/vt.c:673
 redraw_screen+0x64c/0x770 drivers/tty/vt/vt.c:1029
 fbcon_do_set_font+0x7ec/0x950 drivers/video/fbdev/core/fbcon.c:2615
 fbcon_copy_font+0x125/0x190 drivers/video/fbdev/core/fbcon.c:2630
 con_font_copy drivers/tty/vt/vt.c:4627 [inline]
 con_font_op+0x65a/0x1110 drivers/tty/vt/vt.c:4642
 vt_ioctl+0x16dc/0x2670 drivers/tty/vt/vt_ioctl.c:980
 tty_ioctl+0x1019/0x15f0 drivers/tty/tty_io.c:2656
 vfs_ioctl fs/ioctl.c:48 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:753
 __do_sys_ioctl fs/ioctl.c:762 [inline]
 __se_sys_ioctl fs/ioctl.c:760 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cba9
Code: Bad RIP value.
RSP: 002b:00007fc439962c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004e7cc0 RCX: 000000000045cba9
RDX: 0000000020000000 RSI: 0000000000004b72 RDI: 0000000000000004
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000037f R14: 00000000004c629e R15: 00007fc4399636d4

The buggy address belongs to the variable:
 __func__.0+0x120/0x1c0

Memory state around the buggy address:
 ffffffff88965f00: 00 03 fa fa fa fa fa fa 00 01 fa fa fa fa fa fa
 ffffffff88965f80: 04 fa fa fa fa fa fa fa 04 fa fa fa fa fa fa fa
>ffffffff88966000: 04 fa fa fa fa fa fa fa 04 fa fa fa fa fa fa fa
                               ^
 ffffffff88966080: 07 fa fa fa fa fa fa fa 04 fa fa fa fa fa fa fa
 ffffffff88966100: 00 04 fa fa fa fa fa fa 00 02 fa fa fa fa fa fa
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