================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:373 [inline] BUG: KASAN: slab-out-of-bounds in fbcon_get_font+0x2f4/0x6f0 drivers/video/fbdev/core/fbcon.c:2446 Read of size 16 at addr ffff88809e15f3d0 by task syz-executor.0/25220 CPU: 0 PID: 25220 Comm: syz-executor.0 Not tainted 4.19.139-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+0x1fc/0x2fe lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1c7 mm/kasan/report.c:354 kasan_report+0x8f/0x96 mm/kasan/report.c:412 memcpy+0x20/0x50 mm/kasan/kasan.c:302 memcpy include/linux/string.h:373 [inline] fbcon_get_font+0x2f4/0x6f0 drivers/video/fbdev/core/fbcon.c:2446 con_font_get drivers/tty/vt/vt.c:4444 [inline] con_font_op+0x1f7/0x10e0 drivers/tty/vt/vt.c:4603 vt_ioctl+0x167e/0x24d0 drivers/tty/vt/vt_ioctl.c:980 tty_ioctl+0x5b0/0x15c0 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45ce69 Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f09872a8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000f600 RCX: 000000000045ce69 RDX: 00000000200006c0 RSI: 0000000000004b72 RDI: 0000000000000003 RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffc2532a77f R14: 00007f09872a99c0 R15: 000000000118bf2c Allocated by task 24003: __do_kmalloc mm/slab.c:3727 [inline] __kmalloc+0x15a/0x3c0 mm/slab.c:3736 kmalloc include/linux/slab.h:520 [inline] fbcon_set_font+0x34f/0x8a0 drivers/video/fbdev/core/fbcon.c:2644 con_font_set drivers/tty/vt/vt.c:4536 [inline] con_font_op+0xd02/0x10e0 drivers/tty/vt/vt.c:4601 vt_ioctl+0x116d/0x24d0 drivers/tty/vt/vt_ioctl.c:928 tty_ioctl+0x5b0/0x15c0 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 3709: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 uevent_show+0x2bd/0x370 drivers/base/core.c:1233 dev_attr_show+0x4f/0x90 drivers/base/core.c:935 sysfs_kf_seq_show+0x1f8/0x400 fs/sysfs/file.c:61 seq_read+0x4be/0x1160 fs/seq_file.c:229 kernfs_fop_read+0xe9/0x550 fs/kernfs/file.c:252 __vfs_read+0xf7/0x750 fs/read_write.c:416 vfs_read+0x194/0x3c0 fs/read_write.c:452 ksys_read+0x12b/0x2a0 fs/read_write.c:579 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88809e15e6c0 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 3344 bytes inside of 4096-byte region [ffff88809e15e6c0, ffff88809e15f6c0) The buggy address belongs to the page: page:ffffea0002785780 count:1 mapcount:0 mapping:ffff88812c39cdc0 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffffea0001264f88 ffffea00013ae888 ffff88812c39cdc0 raw: 0000000000000000 ffff88809e15e6c0 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809e15f280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88809e15f300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88809e15f380: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ^ ffff88809e15f400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809e15f480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================