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BUG: KASAN: global-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:641 [inline]
BUG: KASAN: global-out-of-bounds in bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:95 [inline]
BUG: KASAN: global-out-of-bounds in bit_putcs+0xa63/0xde0 drivers/video/fbdev/core/bitblit.c:184
Read of size 1 at addr ffffffff8c18eb30 by task syz.8.2294/24198

CPU: 3 UID: 0 PID: 24198 Comm: syz.8.2294 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 __fb_pad_aligned_buffer include/linux/fb.h:641 [inline]
 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:95 [inline]
 bit_putcs+0xa63/0xde0 drivers/video/fbdev/core/bitblit.c:184
 fbcon_putcs+0x384/0x4a0 drivers/video/fbdev/core/fbcon.c:1327
 fbcon_redraw+0x2d4/0x510 drivers/video/fbdev/core/fbcon.c:1672
 fbcon_scroll+0x2d1/0x690 drivers/video/fbdev/core/fbcon.c:1954
 con_scroll+0x45c/0x690 drivers/tty/vt/vt.c:587
 csi_L drivers/tty/vt/vt.c:2075 [inline]
 csi_ECMA drivers/tty/vt/vt.c:2501 [inline]
 do_con_trol drivers/tty/vt/vt.c:2678 [inline]
 do_con_write+0x415e/0x8280 drivers/tty/vt/vt.c:3174
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3516
 process_output_block drivers/tty/n_tty.c:561 [inline]
 n_tty_write+0x41c/0x11e0 drivers/tty/n_tty.c:2377
 iterate_tty_write drivers/tty/tty_io.c:1006 [inline]
 file_tty_write.constprop.0+0x504/0x9b0 drivers/tty/tty_io.c:1081
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d3/0x11d0 fs/read_write.c:686
 ksys_write+0x12a/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fef0718ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fef07fbf038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fef073c5fa0 RCX: 00007fef0718ebe9
RDX: 0000000000001006 RSI: 0000200000001040 RDI: 0000000000000007
RBP: 00007fef07211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fef073c6038 R14: 00007fef073c5fa0 R15: 00007ffcaaf5bbd8
 </TASK>

The buggy address belongs to the variable:
 fontdata_8x16+0x1010/0x1140

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xc18e
flags: 0xfff00000002000(reserved|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000002000 ffffea0000306388 ffffea0000306388 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffffffff8c18ea00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffffff8c18ea80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffffff8c18eb00: 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9 06 f9 f9 f9
                                     ^
 ffffffff8c18eb80: f9 f9 f9 f9 05 f9 f9 f9 f9 f9 f9 f9 06 f9 f9 f9
 ffffffff8c18ec00: f9 f9 f9 f9 00 00 03 f9 f9 f9 f9 f9 00 00 00 00
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