audit: type=1400 audit(1575866296.562:36): avc: denied { map } for pid=6961 comm="syz-executor117" path="/root/syz-executor117208043" dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 ================================================================== BUG: KASAN: slab-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:663 [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+0xc09/0xdb0 drivers/video/fbdev/core/bitblit.c:185 Read of size 1 at addr ffff88808fc49664 by task syz-executor117/7007 CPU: 0 PID: 7007 Comm: syz-executor117 Not tainted 4.14.158-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x142/0x197 lib/dump_stack.c:58 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:427 __fb_pad_aligned_buffer include/linux/fb.h:663 [inline] bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] bit_putcs+0xc09/0xdb0 drivers/video/fbdev/core/bitblit.c:185 fbcon_putcs+0x3c2/0x480 drivers/video/fbdev/core/fbcon.c:1298 do_update_region+0x3b3/0x650 drivers/tty/vt/vt.c:373 redraw_screen+0x589/0x7c0 drivers/tty/vt/vt.c:704 fbcon_do_set_font+0x6d1/0x9a0 drivers/video/fbdev/core/fbcon.c:2561 fbcon_copy_font+0x12c/0x190 drivers/video/fbdev/core/fbcon.c:2576 con_font_copy drivers/tty/vt/vt.c:4218 [inline] con_font_op+0x5c6/0x1060 drivers/tty/vt/vt.c:4233 vt_ioctl+0x179f/0x2170 drivers/tty/vt/vt_ioctl.c:979 tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x447079 RSP: 002b:00007fdd7e4a8ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000006dcc78 RCX: 0000000000447079 RDX: 0000000020000000 RSI: 0000000000004b72 RDI: 0000000000000005 RBP: 00000000006dcc70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dcc7c R13: 00007ffde6ab184f R14: 00007fdd7e4a99c0 R15: 0000000000000003 Allocated by task 6971: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc mm/kasan/kasan.c:551 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529 __do_kmalloc mm/slab.c:3720 [inline] __kmalloc+0x15d/0x7a0 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] fbcon_set_font+0x2f8/0x7b0 drivers/video/fbdev/core/fbcon.c:2618 con_font_set drivers/tty/vt/vt.c:4162 [inline] con_font_op+0xc0f/0x1060 drivers/tty/vt/vt.c:4227 vt_ioctl+0xb80/0x2170 drivers/tty/vt/vt_ioctl.c:927 tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Freed by task 5461: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xcc/0x270 mm/slab.c:3815 load_elf_binary+0x1e57/0x4d60 fs/binfmt_elf.c:1096 search_binary_handler fs/exec.c:1638 [inline] search_binary_handler+0x149/0x6f0 fs/exec.c:1616 exec_binprm fs/exec.c:1680 [inline] do_execveat_common.isra.0+0x1000/0x1dd0 fs/exec.c:1802 do_execve fs/exec.c:1847 [inline] SYSC_execve fs/exec.c:1928 [inline] SyS_execve+0x39/0x50 fs/exec.c:1923 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 The buggy address belongs to the object at ffff88808fc49500 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 356 bytes inside of 512-byte region [ffff88808fc49500, ffff88808fc49700) The buggy address belongs to the page: page:ffffea00023f1240 count:1 mapcount:0 mapping:ffff88808fc49000 index:0x0 flags: 0xfffe0000000100(slab) raw: 00fffe0000000100 ffff88808fc49000 0000000000000000 0000000100000006 raw: ffffea00024377a0 ffffea00023f78a0 ffff8880aa800940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808fc49500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88808fc49580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88808fc49600: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88808fc49680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808fc49700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================