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BUG: KASAN: global-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:674 [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+0xd5d/0xf10 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffffffff87ecaea0 by task syz-executor617/16508

CPU: 0 PID: 16508 Comm: syz-executor617 Not tainted 4.19.87-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+0x197/0x210 lib/dump_stack.c:118
 print_address_description.cold+0x5/0x20d mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
 __fb_pad_aligned_buffer include/linux/fb.h:674 [inline]
 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline]
 bit_putcs+0xd5d/0xf10 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x42b/0x4f0 drivers/video/fbdev/core/fbcon.c:1320
 con_flush drivers/tty/vt/vt.c:2522 [inline]
 do_con_write.part.0+0xfb1/0x1eb0 drivers/tty/vt/vt.c:2772
 do_con_write drivers/tty/vt/vt.c:2541 [inline]
 con_write+0x46/0xd0 drivers/tty/vt/vt.c:3110
 process_output_block drivers/tty/n_tty.c:593 [inline]
 n_tty_write+0x3f9/0x10f0 drivers/tty/n_tty.c:2331
 do_tty_write drivers/tty/tty_io.c:960 [inline]
 tty_write+0x458/0x7a0 drivers/tty/tty_io.c:1044
 __vfs_write+0x114/0x810 fs/read_write.c:485
 vfs_write+0x20c/0x560 fs/read_write.c:549
 ksys_write+0x14f/0x2d0 fs/read_write.c:599
 __do_sys_write fs/read_write.c:611 [inline]
 __se_sys_write fs/read_write.c:608 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:608
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x448349
Code: e8 4c 15 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0f 83 cb 05 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f1127d83ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00000000006dec68 RCX: 0000000000448349
RDX: 0000000000800000 RSI: 0000000020000000 RDI: 0000000000000004
RBP: 00000000006dec60 R08: 00007f1127d84700 R09: 0000000000000000
R10: 00007f1127d84700 R11: 0000000000000246 R12: 00000000006dec6c
R13: 00007ffd67765a0f R14: 00007f1127d849c0 R15: 0000000000000003

The buggy address belongs to the variable:
 str__msr__trace_system_name+0x140/0x940

Memory state around the buggy address:
 ffffffff87ecad80: fa fa fa fa 00 00 01 fa fa fa fa fa 04 fa fa fa
 ffffffff87ecae00: fa fa fa fa 00 00 00 00 06 fa fa fa fa fa fa fa
>ffffffff87ecae80: 00 00 00 fa fa fa fa fa 00 00 00 fa fa fa fa fa
                               ^
 ffffffff87ecaf00: 00 00 00 03 fa fa fa fa 00 00 00 04 fa fa fa fa
 ffffffff87ecaf80: 00 00 00 00 03 fa fa fa fa fa fa fa 00 00 07 fa
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