audit: type=1400 audit(1591459316.034:8): avc:  denied  { execmem } for  pid=6344 comm="syz-executor743" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1
==================================================================
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+0xa8a/0xc00 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffffffff86c69472 by task syz-executor743/6346

CPU: 1 PID: 6346 Comm: syz-executor743 Not tainted 4.14.183-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+0x1b2/0x283 lib/dump_stack.c:58
 print_address_description.cold+0x5/0x1dc mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0xa9/0x2b9 mm/kasan/report.c:393
 __fb_pad_aligned_buffer include/linux/fb.h:663 [inline]
 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline]
 bit_putcs+0xa8a/0xc00 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x3bb/0x480 drivers/video/fbdev/core/fbcon.c:1301
 con_flush drivers/tty/vt/vt.c:2199 [inline]
 do_con_write.part.0+0xc27/0x1a20 drivers/tty/vt/vt.c:2446
 do_con_write drivers/tty/vt/vt.c:2218 [inline]
 con_write+0x33/0xc0 drivers/tty/vt/vt.c:2798
 process_output_block drivers/tty/n_tty.c:595 [inline]
 n_tty_write+0x375/0xe20 drivers/tty/n_tty.c:2333
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x3f1/0x6e0 drivers/tty/tty_io.c:1043
 do_loop_readv_writev fs/read_write.c:698 [inline]
 do_loop_readv_writev fs/read_write.c:682 [inline]
 do_iter_write fs/read_write.c:956 [inline]
 do_iter_write+0x3d9/0x550 fs/read_write.c:935
 vfs_writev+0x133/0x2a0 fs/read_write.c:999
 do_writev+0xfc/0x2c0 fs/read_write.c:1034
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x4412c9
RSP: 002b:00007fffe80457e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004412c9
RDX: 0000000000000003 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 0000000000007f3e R08: 000000000000000d R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004020f0
R13: 0000000000402180 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the variable:
 str__msr__trace_system_name+0x112/0x9a0

Memory state around the buggy address:
 ffffffff86c69300: fa fa fa fa 00 03 fa fa fa fa fa fa 04 fa fa fa
 ffffffff86c69380: fa fa fa fa 00 00 01 fa fa fa fa fa 00 00 00 02
>ffffffff86c69400: fa fa fa fa 00 00 07 fa fa fa fa fa 00 00 02 fa
                                                             ^
 ffffffff86c69480: fa fa fa fa 00 04 fa fa fa fa fa fa 00 02 fa fa
 ffffffff86c69500: fa fa fa fa 00 00 01 fa fa fa fa fa 04 fa fa fa
==================================================================