==================================================================
BUG: KASAN: slab-out-of-bounds in soft_cursor+0x972/0xa30 drivers/video/fbdev/core/softcursor.c:61
Read of size 1 at addr ffff8880494aec68 by task kworker/0:1/14

CPU: 0 PID: 14 Comm: kworker/0:1 Not tainted 4.19.96-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_power_efficient fb_flashcursor
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 print_address_description.cold+0x7c/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
 soft_cursor+0x972/0xa30 drivers/video/fbdev/core/softcursor.c:61
 bit_cursor+0x12fc/0x1a60 drivers/video/fbdev/core/bitblit.c:386
 fb_flashcursor+0x3a6/0x450 drivers/video/fbdev/core/fbcon.c:399
 process_one_work+0x989/0x1750 kernel/workqueue.c:2153
 worker_thread+0x98/0xe40 kernel/workqueue.c:2296
 kthread+0x354/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Allocated by task 26945:
 save_stack+0x45/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc mm/kasan/kasan.c:553 [inline]
 kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531
 __do_kmalloc mm/slab.c:3727 [inline]
 __kmalloc+0x15d/0x750 mm/slab.c:3736
 kmalloc include/linux/slab.h:520 [inline]
 fbcon_set_font+0x32d/0x860 drivers/video/fbdev/core/fbcon.c:2641
 con_font_set drivers/tty/vt/vt.c:4492 [inline]
 con_font_op+0xe18/0x1250 drivers/tty/vt/vt.c:4557
 vt_ioctl+0xd2e/0x2530 drivers/tty/vt/vt_ioctl.c:913
 tty_ioctl+0x7f3/0x1510 drivers/tty/tty_io.c:2669
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 5825:
 save_stack+0x45/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcf/0x220 mm/slab.c:3822
 free_pipe_info+0x24b/0x300 fs/pipe.c:698
 put_pipe_info+0xd0/0xf0 fs/pipe.c:570
 pipe_release+0x1e6/0x280 fs/pipe.c:591
 __fput+0x2dd/0x8b0 fs/file_table.c:278
 ____fput+0x16/0x20 fs/file_table.c:309
 task_work_run+0x145/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:167
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x53d/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880494aea80
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 488 bytes inside of
 512-byte region [ffff8880494aea80, ffff8880494aec80)
The buggy address belongs to the page:
page:ffffea0001252b80 count:1 mapcount:0 mapping:ffff88812c31c940 index:0xffff8880494ae300
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffffea0002818e48 ffffea0001a7f848 ffff88812c31c940
raw: ffff8880494ae300 ffff8880494ae080 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880494aeb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880494aeb80: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880494aec00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                          ^
 ffff8880494aec80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880494aed00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================