================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:380 [inline] BUG: KASAN: slab-out-of-bounds in fbcon_get_font+0x2b2/0x5e0 drivers/video/fbdev/core/fbcon.c:2465 Read of size 5 at addr ffff8880a283540c by task syz-executor713/11451 CPU: 1 PID: 11451 Comm: syz-executor713 Not tainted 5.5.0-rc1-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:380 [inline] fbcon_get_font+0x2b2/0x5e0 drivers/video/fbdev/core/fbcon.c:2465 con_font_get drivers/tty/vt/vt.c:4446 [inline] con_font_op+0x20b/0x1270 drivers/tty/vt/vt.c:4605 vt_ioctl+0xd2e/0x26d0 drivers/tty/vt/vt_ioctl.c:913 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: 0033:0x448549 Code: e8 1c e6 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 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 8b 06 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f662c161db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000006e49e8 RCX: 0000000000448549 RDX: 0000000020000140 RSI: 0000000000004b60 RDI: 0000000000000003 RBP: 00000000006e49e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006e49ec R13: 00007fff9641cc3f R14: 00007f662c1629c0 R15: 20c49ba5e353f7cf Allocated by task 11446: 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] fbcon_set_font+0x32d/0x860 drivers/video/fbdev/core/fbcon.c:2663 con_font_set drivers/tty/vt/vt.c:4538 [inline] con_font_op+0xe30/0x1270 drivers/tty/vt/vt.c:4603 vt_ioctl+0xd2e/0x26d0 drivers/tty/vt/vt_ioctl.c:913 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 Freed by task 12: 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 free_tty_struct+0x95/0xc0 drivers/tty/tty_io.c:177 release_one_tty+0x28c/0x360 drivers/tty/tty_io.c:1468 process_one_work+0x9af/0x1740 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff8880a2835000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1036 bytes inside of 2048-byte region [ffff8880a2835000, ffff8880a2835800) The buggy address belongs to the page: page:ffffea00028a0d40 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 raw: 00fffe0000000200 ffffea00023c2ac8 ffffea000259c108 ffff8880aa400e00 raw: 0000000000000000 ffff8880a2835000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a2835300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880a2835380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880a2835400: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880a2835480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a2835500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================