overlayfs: fs on './file0' does not support file handles, falling back to index=off.
==================================================================
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+0xab7/0xc30 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffff8880919a3c52 by task syz-executor.1/27675

CPU: 0 PID: 27675 Comm: syz-executor.1 Not tainted 4.14.232-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+0x1b2/0x281 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_load1_noabort+0x68/0x70 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+0xab7/0xc30 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x2fe/0x480 drivers/video/fbdev/core/fbcon.c:1247
 con_flush drivers/tty/vt/vt.c:2206 [inline]
 do_con_write+0x9dd/0x19b0 drivers/tty/vt/vt.c:2453
 con_write+0x21/0xa0 drivers/tty/vt/vt.c:2805
 n_tty_write+0x85e/0xda0 drivers/tty/n_tty.c:2356
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
 do_loop_readv_writev fs/read_write.c:698 [inline]
 do_loop_readv_writev fs/read_write.c:682 [inline]
 do_iter_write+0x3da/0x550 fs/read_write.c:956
 vfs_writev+0x125/0x290 fs/read_write.c:999
 do_writev+0xfc/0x2c0 fs/read_write.c:1034
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x4665d9
RSP: 002b:00007fd4e0487188 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665d9
RDX: 0000000000000006 RSI: 0000000020000340 RDI: 0000000000000003
RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fff04cc819f R14: 00007fd4e0487300 R15: 0000000000022000

Allocated by task 10999:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551
 __do_kmalloc mm/slab.c:3720 [inline]
 __kmalloc+0x15a/0x400 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 fbcon_set_font+0x2fb/0x7c0 drivers/video/fbdev/core/fbcon.c:2459
 con_font_set drivers/tty/vt/vt.c:4190 [inline]
 con_font_op+0x9e8/0xdb0 drivers/tty/vt/vt.c:4234
 vt_ioctl+0xd5d/0x1d50 drivers/tty/vt/vt_ioctl.c:938
 tty_ioctl+0x50f/0x13c0 drivers/tty/tty_io.c:2661
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

Freed by task 9779:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kfree+0xc9/0x250 mm/slab.c:3815
 skb_free_head net/core/skbuff.c:563 [inline]
 skb_release_data+0x5f6/0x820 net/core/skbuff.c:583
 skb_release_all net/core/skbuff.c:640 [inline]
 __kfree_skb net/core/skbuff.c:654 [inline]
 kfree_skb+0xe7/0x390 net/core/skbuff.c:672
 __netif_receive_skb_core+0x427/0x2a30 net/core/dev.c:4481
 __netif_receive_skb+0x27/0x1a0 net/core/dev.c:4512
 netif_receive_skb_internal+0xd7/0x580 net/core/dev.c:4585
 tun_rx_batched.isra.0+0x45c/0x700 drivers/net/tun.c:1229
 tun_get_user+0x11f8/0x4510 drivers/net/tun.c:1589
 tun_chr_write_iter+0xe8/0x1e0 drivers/net/tun.c:1620
 call_write_iter include/linux/fs.h:1778 [inline]
 new_sync_write fs/read_write.c:469 [inline]
 __vfs_write+0x44c/0x630 fs/read_write.c:482
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

The buggy address belongs to the object at ffff8880919a1d80
 which belongs to the cache kmalloc-8192 of size 8192
The buggy address is located 7890 bytes inside of
 8192-byte region [ffff8880919a1d80, ffff8880919a3d80)
The buggy address belongs to the page:
page:ffffea0002466800 count:1 mapcount:0 mapping:ffff8880919a1d80 index:0x0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffff8880919a1d80 0000000000000000 0000000100000001
raw: ffffea0002701720 ffffea0001236120 ffff88813fe09080 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880919a3b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880919a3b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880919a3c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                 ^
 ffff8880919a3c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880919a3d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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