================================================================== 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 ffffffff87cf6a50 by task syz-executor.2/17163 CPU: 0 PID: 17163 Comm: syz-executor.2 Not tainted 4.14.231-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 con_flush drivers/tty/vt/vt.c:2206 [inline] do_con_write+0x9dd/0x19b0 drivers/tty/vt/vt.c:2453 con_write+0x21/0xa0 drivers/tty/vt/vt.c:2805 process_output_block drivers/tty/n_tty.c:595 [inline] n_tty_write+0x352/0xda0 drivers/tty/n_tty.c:2333 do_tty_write drivers/tty/tty_io.c:959 [inline] tty_write+0x410/0x740 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+0x3da/0x550 fs/read_write.c:956 vfs_writev+0x125/0x290 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: 0033:0x466459 RSP: 002b:00007fa3cc1ec188 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000001 RSI: 0000000020000400 RDI: 0000000000000003 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffefe549b1f R14: 00007fa3cc1ec300 R15: 0000000000022000 The buggy address belongs to the variable: str__msr__trace_system_name+0x1f0/0xb00 Memory state around the buggy address: 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 ^ ffffffff87cf6a80: fa fa fa fa 00 00 02 fa fa fa fa fa 00 04 fa fa ffffffff87cf6b00: fa fa fa fa 00 02 fa fa fa fa fa fa 04 fa fa fa ==================================================================