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BUG: KASAN: global-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:663 [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+0xab7/0xc30 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffffffff87cf697b by task syz-executor.5/29044

CPU: 0 PID: 29044 Comm: syz-executor.5 Not tainted 4.14.232-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 print_address_description.cold+0x5/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_load1_noabort+0x68/0x70 mm/kasan/report.c:427
 __fb_pad_aligned_buffer include/linux/fb.h:663 [inline]
 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline]
 bit_putcs+0xab7/0xc30 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x2fe/0x480 drivers/video/fbdev/core/fbcon.c:1247
 do_update_region+0x34b/0x5b0 drivers/tty/vt/vt.c:373
 update_region+0xd7/0x110 drivers/tty/vt/vt.c:391
 vcs_write+0x3b9/0xb40 drivers/tty/vt/vc_screen.c:549
 __vfs_write+0xe4/0x630 fs/read_write.c:480
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x4665f9
RSP: 002b:00007fd2bb33b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9
RDX: 0000000000000160 RSI: 0000000020004580 RDI: 0000000000000003
RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffe9ff2c6ef R14: 00007fd2bb33b300 R15: 0000000000022000

The buggy address belongs to the variable:
 str__msr__trace_system_name+0x11b/0xb00

Memory state around the buggy address:
 ffffffff87cf6800: fa fa fa fa 00 03 fa fa fa fa fa fa 04 fa fa fa
 ffffffff87cf6880: fa fa fa fa 00 03 fa fa fa fa fa fa 05 fa fa fa
>ffffffff87cf6900: fa fa fa fa 00 06 fa fa fa fa fa fa 00 00 00 03
                                                                ^
 ffffffff87cf6980: fa fa fa fa 00 02 fa fa fa fa fa fa 00 00 07 fa
 ffffffff87cf6a00: fa fa fa fa 00 00 07 fa fa fa fa fa 00 00 01 fa
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