================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:406 [inline] BUG: KASAN: slab-out-of-bounds in soft_cursor+0x44b/0xa30 drivers/video/fbdev/core/softcursor.c:70 Read of size 9 at addr ffff88805f933d30 by task kworker/0:19/2978 CPU: 0 PID: 2978 Comm: kworker/0:19 Not tainted 5.9.0-rc5-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+0x198/0x1fd lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 check_memory_region_inline mm/kasan/generic.c:186 [inline] check_memory_region+0x13d/0x180 mm/kasan/generic.c:192 memcpy+0x20/0x60 mm/kasan/common.c:105 memcpy include/linux/string.h:406 [inline] soft_cursor+0x44b/0xa30 drivers/video/fbdev/core/softcursor.c:70 bit_cursor+0xcfe/0x1720 drivers/video/fbdev/core/bitblit.c:377 fb_flashcursor+0x36d/0x3e0 drivers/video/fbdev/core/fbcon.c:397 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Allocated by task 16188: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 __do_kmalloc mm/slab.c:3655 [inline] __kmalloc+0x1b0/0x310 mm/slab.c:3664 kmalloc include/linux/slab.h:559 [inline] fbcon_set_font+0x34f/0x8b0 drivers/video/fbdev/core/fbcon.c:2496 con_font_set drivers/tty/vt/vt.c:4663 [inline] con_font_op+0xd25/0x1110 drivers/tty/vt/vt.c:4728 vt_io_ioctl drivers/tty/vt/vt_ioctl.c:595 [inline] vt_ioctl+0x1952/0x2cc0 drivers/tty/vt/vt_ioctl.c:856 tty_ioctl+0x1019/0x15f0 drivers/tty/tty_io.c:2656 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff88805f933c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 304 bytes inside of 512-byte region [ffff88805f933c00, ffff88805f933e00) The buggy address belongs to the page: page:00000000c2022d04 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805f933400 pfn:0x5f933 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00029e6348 ffffea00023f6d88 ffff8880aa040600 raw: ffff88805f933400 ffff88805f933000 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88805f933c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805f933c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88805f933d00: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88805f933d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805f933e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================