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BUG: KASAN: use-after-free in memcpy include/linux/string.h:425 [inline]
BUG: KASAN: use-after-free in soft_cursor+0x439/0xa30 drivers/video/fbdev/core/softcursor.c:70
Read of size 9 at addr ffff88809fc99451 by task syz-executor426/9167

CPU: 1 PID: 9167 Comm: syz-executor426 Not tainted 5.5.0-rc2-next-20191218-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/0x41 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:639
 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:125
 memcpy include/linux/string.h:425 [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:1402
 hide_cursor+0x9d/0x2b0 drivers/tty/vt/vt.c:895
 redraw_screen+0x60b/0x7d0 drivers/tty/vt/vt.c:988
 vc_do_resize+0x10c9/0x1460 drivers/tty/vt/vt.c:1284
 vc_resize+0x4d/0x60 drivers/tty/vt/vt.c:1304
 vt_ioctl+0x2076/0x26d0 drivers/tty/vt/vt_ioctl.c:887
 tty_ioctl+0xa37/0x14f0 drivers/tty/tty_io.c:2660
 vfs_ioctl fs/ioctl.c:47 [inline]
 file_ioctl fs/ioctl.c:545 [inline]
 do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749
 __do_sys_ioctl fs/ioctl.c:756 [inline]
 __se_sys_ioctl fs/ioctl.c:754 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440219
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:00007ffe9e4c5938 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440219
RDX: 00000000200002c0 RSI: 000000000000560a RDI: 0000000000000004
RBP: 00000000006ca018 R08: 0000000000000001 R09: 00000000004002c8
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000401b00
R13: 0000000000401b90 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 8909:
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527
 __do_kmalloc mm/slab.c:3656 [inline]
 __kmalloc+0x163/0x770 mm/slab.c:3665
 kmalloc include/linux/slab.h:561 [inline]
 kzalloc include/linux/slab.h:670 [inline]
 tomoyo_init_log+0x141f/0x2070 security/tomoyo/audit.c:275
 tomoyo_supervisor+0x33f/0xef0 security/tomoyo/common.c:2097
 tomoyo_audit_net_log security/tomoyo/network.c:367 [inline]
 tomoyo_audit_unix_log security/tomoyo/network.c:406 [inline]
 tomoyo_unix_entry+0x43f/0x5d0 security/tomoyo/network.c:574
 tomoyo_check_unix_address security/tomoyo/network.c:605 [inline]
 tomoyo_socket_connect_permission+0x331/0x380 security/tomoyo/network.c:709
 tomoyo_socket_connect+0x26/0x30 security/tomoyo/tomoyo.c:456
 security_socket_connect+0x77/0xc0 security/security.c:2054
 __sys_connect_file+0xae/0x1c0 net/socket.c:1852
 __sys_connect+0x174/0x1b0 net/socket.c:1873
 __do_sys_connect net/socket.c:1884 [inline]
 __se_sys_connect net/socket.c:1881 [inline]
 __x64_sys_connect+0x73/0xb0 net/socket.c:1881
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 8909:
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 kasan_set_free_info mm/kasan/common.c:335 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:474
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x10a/0x2c0 mm/slab.c:3757
 tomoyo_supervisor+0x360/0xef0 security/tomoyo/common.c:2149
 tomoyo_audit_net_log security/tomoyo/network.c:367 [inline]
 tomoyo_audit_unix_log security/tomoyo/network.c:406 [inline]
 tomoyo_unix_entry+0x43f/0x5d0 security/tomoyo/network.c:574
 tomoyo_check_unix_address security/tomoyo/network.c:605 [inline]
 tomoyo_socket_connect_permission+0x331/0x380 security/tomoyo/network.c:709
 tomoyo_socket_connect+0x26/0x30 security/tomoyo/tomoyo.c:456
 security_socket_connect+0x77/0xc0 security/security.c:2054
 __sys_connect_file+0xae/0x1c0 net/socket.c:1852
 __sys_connect+0x174/0x1b0 net/socket.c:1873
 __do_sys_connect net/socket.c:1884 [inline]
 __se_sys_connect net/socket.c:1881 [inline]
 __x64_sys_connect+0x73/0xb0 net/socket.c:1881
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88809fc99400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 81 bytes inside of
 512-byte region [ffff88809fc99400, ffff88809fc99600)
The buggy address belongs to the page:
page:ffffea00027f2640 refcount:1 mapcount:0 mapping:ffff8880aa400a80 index:0x0
raw: 00fffe0000000200 ffffea00027889c8 ffffea00029a7148 ffff8880aa400a80
raw: 0000000000000000 ffff88809fc99000 0000000100000004 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809fc99300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88809fc99380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88809fc99400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88809fc99480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88809fc99500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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