================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:381 [inline] BUG: KASAN: slab-out-of-bounds in soft_cursor+0x439/0xa30 drivers/video/fbdev/core/softcursor.c:70 Read of size 64 at addr ffff8880a2c25950 by task syz-executor556/9728 CPU: 1 PID: 9728 Comm: syz-executor556 Not tainted 5.6.0-rc3-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.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x32 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:641 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 memcpy+0x24/0x50 mm/kasan/common.c:127 memcpy include/linux/string.h:381 [inline] soft_cursor+0x439/0xa30 drivers/video/fbdev/core/softcursor.c:70 bit_cursor+0x12fc/0x1a60 drivers/video/fbdev/core/bitblit.c:386 fbcon_cursor+0x487/0x660 drivers/video/fbdev/core/fbcon.c:1409 hide_cursor+0x9d/0x2b0 drivers/tty/vt/vt.c:895 redraw_screen+0x60b/0x7d0 drivers/tty/vt/vt.c:999 vc_do_resize+0x10c9/0x1460 drivers/tty/vt/vt.c:1295 vc_resize+0x4d/0x60 drivers/tty/vt/vt.c:1315 vt_ioctl+0x207b/0x26c0 drivers/tty/vt/vt_ioctl.c:891 tty_ioctl+0xa37/0x14f0 drivers/tty/tty_io.c:2660 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440269 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 5b 14 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffe157a26c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440269 RDX: 0000000020000080 RSI: 000000000000560a RDI: 0000000000000004 RBP: 00000000006cb018 R08: 0000000000000001 R09: 00000000004002c8 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000401b50 R13: 0000000000401be0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 9728: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:515 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:488 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:529 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc+0x163/0x770 mm/slab.c:3665 kmalloc include/linux/slab.h:560 [inline] fbcon_set_font+0x32d/0x860 drivers/video/fbdev/core/fbcon.c:2670 con_font_set drivers/tty/vt/vt.c:4549 [inline] con_font_op+0xe30/0x1270 drivers/tty/vt/vt.c:4614 vt_ioctl+0x181a/0x26c0 drivers/tty/vt/vt_ioctl.c:970 tty_ioctl+0xa37/0x14f0 drivers/tty/tty_io.c:2660 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8880a2c24000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 6480 bytes inside of 8192-byte region [ffff8880a2c24000, ffff8880a2c26000) The buggy address belongs to the page: page:ffffea00028b0900 refcount:1 mapcount:0 mapping:ffff8880aa4021c0 index:0x0 compound_mapcount: 0 flags: 0xfffe0000010200(slab|head) raw: 00fffe0000010200 ffffea00024cb308 ffffea00025fa408 ffff8880aa4021c0 raw: 0000000000000000 ffff8880a2c24000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a2c25800: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a2c25880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a2c25900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880a2c25980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a2c25a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================