================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:406 [inline] BUG: KASAN: slab-out-of-bounds in scr_memcpyw include/linux/vt_buffer.h:49 [inline] BUG: KASAN: slab-out-of-bounds in vc_do_resize+0x9d6/0x13f0 drivers/tty/vt/vt.c:1286 Read of size 4 at addr ffff88809f9aa5e0 by task syz-executor.0/7036 CPU: 1 PID: 7036 Comm: syz-executor.0 Not tainted 5.8.0-rc7-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+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x436 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] scr_memcpyw include/linux/vt_buffer.h:49 [inline] vc_do_resize+0x9d6/0x13f0 drivers/tty/vt/vt.c:1286 fbcon_modechanged+0x36c/0x710 drivers/video/fbdev/core/fbcon.c:2990 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0xae8/0xd60 drivers/video/fbdev/core/fbmem.c:1056 do_fb_ioctl+0x33f/0x6c0 drivers/video/fbdev/core/fbmem.c:1109 fb_compat_ioctl+0x175/0xc10 drivers/video/fbdev/core/fbmem.c:1315 __do_compat_sys_ioctl+0x1d3/0x230 fs/ioctl.c:847 do_syscall_32_irqs_on+0x3f/0x60 arch/x86/entry/common.c:428 __do_fast_syscall_32 arch/x86/entry/common.c:475 [inline] do_fast_syscall_32+0x7f/0x120 arch/x86/entry/common.c:503 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7fe8569 Code: 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f7fe30cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000004601 RDX: 0000000020000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 7036: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:494 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc+0x17a/0x340 mm/slab.c:3665 bit_cursor+0x8a3/0x17d0 drivers/video/fbdev/core/bitblit.c:315 fbcon_cursor+0x52b/0x650 drivers/video/fbdev/core/fbcon.c:1411 set_cursor drivers/tty/vt/vt.c:915 [inline] set_cursor+0x1dd/0x230 drivers/tty/vt/vt.c:906 redraw_screen+0x4b7/0x770 drivers/tty/vt/vt.c:1031 vc_do_resize+0x1111/0x13f0 drivers/tty/vt/vt.c:1320 fbcon_modechanged+0x36c/0x710 drivers/video/fbdev/core/fbcon.c:2990 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0xae8/0xd60 drivers/video/fbdev/core/fbmem.c:1056 fbcon_resize+0x575/0x610 drivers/video/fbdev/core/fbcon.c:2231 resize_screen drivers/tty/vt/vt.c:1170 [inline] vc_do_resize+0x53e/0x13f0 drivers/tty/vt/vt.c:1241 fbcon_modechanged+0x36c/0x710 drivers/video/fbdev/core/fbcon.c:2990 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0xae8/0xd60 drivers/video/fbdev/core/fbmem.c:1056 do_fb_ioctl+0x33f/0x6c0 drivers/video/fbdev/core/fbmem.c:1109 fb_compat_ioctl+0x175/0xc10 drivers/video/fbdev/core/fbmem.c:1315 __do_compat_sys_ioctl+0x1d3/0x230 fs/ioctl.c:847 do_syscall_32_irqs_on+0x3f/0x60 arch/x86/entry/common.c:428 __do_fast_syscall_32 arch/x86/entry/common.c:475 [inline] do_fast_syscall_32+0x7f/0x120 arch/x86/entry/common.c:503 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Freed by task 7036: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0xf5/0x140 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kfree+0x103/0x2c0 mm/slab.c:3757 bit_cursor+0x8e7/0x17d0 drivers/video/fbdev/core/bitblit.c:322 fbcon_cursor+0x52b/0x650 drivers/video/fbdev/core/fbcon.c:1411 set_cursor drivers/tty/vt/vt.c:915 [inline] set_cursor+0x1dd/0x230 drivers/tty/vt/vt.c:906 redraw_screen+0x4b7/0x770 drivers/tty/vt/vt.c:1031 fbcon_modechanged+0x575/0x710 drivers/video/fbdev/core/fbcon.c:3001 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0xae8/0xd60 drivers/video/fbdev/core/fbmem.c:1056 fbcon_resize+0x575/0x610 drivers/video/fbdev/core/fbcon.c:2231 resize_screen drivers/tty/vt/vt.c:1170 [inline] vc_do_resize+0x53e/0x13f0 drivers/tty/vt/vt.c:1241 fbcon_modechanged+0x36c/0x710 drivers/video/fbdev/core/fbcon.c:2990 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0xae8/0xd60 drivers/video/fbdev/core/fbmem.c:1056 do_fb_ioctl+0x33f/0x6c0 drivers/video/fbdev/core/fbmem.c:1109 fb_compat_ioctl+0x175/0xc10 drivers/video/fbdev/core/fbmem.c:1315 __do_compat_sys_ioctl+0x1d3/0x230 fs/ioctl.c:847 do_syscall_32_irqs_on+0x3f/0x60 arch/x86/entry/common.c:428 __do_fast_syscall_32 arch/x86/entry/common.c:475 [inline] do_fast_syscall_32+0x7f/0x120 arch/x86/entry/common.c:503 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c The buggy address belongs to the object at ffff88809f9aa5c0 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes to the right of 32-byte region [ffff88809f9aa5c0, ffff88809f9aa5e0) The buggy address belongs to the page: page:ffffea00027e6a80 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88809f9aafc1 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea0002864948 ffff8880aa001240 ffff8880aa0001c0 raw: ffff88809f9aafc1 ffff88809f9aa000 000000010000003c 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809f9aa480: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff88809f9aa500: 00 04 fc fc fc fc fc fc 00 04 fc fc fc fc fc fc >ffff88809f9aa580: 00 00 fc fc fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff88809f9aa600: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff88809f9aa680: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ==================================================================