================================================================== BUG: KASAN: slab-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:654 [inline] BUG: KASAN: slab-out-of-bounds in bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] BUG: KASAN: slab-out-of-bounds in bit_putcs+0xd5d/0xf10 drivers/video/fbdev/core/bitblit.c:185 Read of size 1 at addr ffff88809408f964 by task syz-executor957/9383 CPU: 0 PID: 9383 Comm: syz-executor957 Not tainted 5.5.0-rc2-next-20191220-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 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:132 __fb_pad_aligned_buffer include/linux/fb.h:654 [inline] bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] bit_putcs+0xd5d/0xf10 drivers/video/fbdev/core/bitblit.c:185 fbcon_putcs+0x33c/0x3e0 drivers/video/fbdev/core/fbcon.c:1353 do_update_region+0x42b/0x6f0 drivers/tty/vt/vt.c:677 redraw_screen+0x676/0x7d0 drivers/tty/vt/vt.c:1011 fbcon_do_set_font+0x829/0x960 drivers/video/fbdev/core/fbcon.c:2605 fbcon_copy_font+0x12c/0x190 drivers/video/fbdev/core/fbcon.c:2620 con_font_copy drivers/tty/vt/vt.c:4594 [inline] con_font_op+0x6b2/0x1270 drivers/tty/vt/vt.c:4609 vt_ioctl+0x181a/0x26d0 drivers/tty/vt/vt_ioctl.c:965 tty_ioctl+0xa37/0x14f0 drivers/tty/tty_io.c:2660 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:747 __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: 0033:0x447109 Code: e8 6c e7 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 db 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb980b90db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000006dcc38 RCX: 0000000000447109 RDX: 0000000020000000 RSI: 0000000000004b72 RDI: 0000000000000005 RBP: 00000000006dcc30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dcc3c R13: 00007fff8139b26f R14: 00007fb980b919c0 R15: 00000000006dcc3c Allocated by task 9344: 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:560 [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] ksys_ioctl+0x123/0x180 fs/ioctl.c:747 __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 9041: 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_find_next_domain+0x76a/0x1f6c security/tomoyo/domain.c:885 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:107 [inline] tomoyo_bprm_check_security+0x124/0x1a0 security/tomoyo/tomoyo.c:97 security_bprm_check+0x63/0xb0 security/security.c:817 search_binary_handler+0x71/0x570 fs/exec.c:1650 exec_binprm fs/exec.c:1706 [inline] __do_execve_file.isra.0+0x1329/0x22b0 fs/exec.c:1826 do_execveat_common fs/exec.c:1872 [inline] do_execve fs/exec.c:1889 [inline] __do_sys_execve fs/exec.c:1965 [inline] __se_sys_execve fs/exec.c:1960 [inline] __x64_sys_execve+0x8f/0xc0 fs/exec.c:1960 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 ffff88809408f800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 356 bytes inside of 512-byte region [ffff88809408f800, ffff88809408fa00) The buggy address belongs to the page: page:ffffea00025023c0 refcount:1 mapcount:0 mapping:ffff8880aa400a80 index:0x0 raw: 00fffe0000000200 ffffea00028fdb08 ffffea00027a4308 ffff8880aa400a80 raw: 0000000000000000 ffff88809408f000 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809408f800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88809408f880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88809408f900: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88809408f980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809408fa00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================