==================================================================
BUG: KASAN: slab-out-of-bounds in vcs_scr_readw+0xc2/0xd0 drivers/tty/vt/vt.c:4618
Read of size 2 at addr ffff888096641480 by task syz-executor.1/10023

CPU: 0 PID: 10023 Comm: syz-executor.1 Not tainted 4.19.88-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.cold+0x7c/0x20d mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396
 __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:431
 vcs_scr_readw+0xc2/0xd0 drivers/tty/vt/vt.c:4618
 vcs_write+0x646/0xcf0 drivers/tty/vt/vc_screen.c:526
 __vfs_write+0x114/0x810 fs/read_write.c:485
 vfs_write+0x20c/0x560 fs/read_write.c:549
 ksys_write+0x14f/0x2d0 fs/read_write.c:599
 __do_sys_write fs/read_write.c:611 [inline]
 __se_sys_write fs/read_write.c:608 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:608
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a6f9
Code: ad 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f37ea710c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a6f9
RDX: 000000000000050f RSI: 00000000200008c0 RDI: 000000000000000b
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f37ea7116d4
R13: 00000000004cbad5 R14: 00000000004e56f8 R15: 00000000ffffffff

Allocated by task 12703:
 save_stack+0x45/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc mm/kasan/kasan.c:553 [inline]
 kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531
 __do_kmalloc mm/slab.c:3727 [inline]
 __kmalloc+0x15d/0x750 mm/slab.c:3736
 kmalloc include/linux/slab.h:520 [inline]
 kzalloc include/linux/slab.h:709 [inline]
 vc_do_resize+0x262/0x14a0 drivers/tty/vt/vt.c:1190
 vt_resize+0xaa/0xf0 drivers/tty/vt/vt.c:1328
 tiocswinsz drivers/tty/tty_io.c:2275 [inline]
 tty_ioctl+0xc6c/0x1510 drivers/tty/tty_io.c:2584
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 3668:
 save_stack+0x45/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcf/0x220 mm/slab.c:3822
 skb_free_head+0x99/0xc0 net/core/skbuff.c:554
 skb_release_data+0x619/0x8d0 net/core/skbuff.c:574
 skb_release_all+0x4d/0x60 net/core/skbuff.c:631
 __kfree_skb net/core/skbuff.c:645 [inline]
 consume_skb net/core/skbuff.c:705 [inline]
 consume_skb+0xe2/0x390 net/core/skbuff.c:699
 skb_free_datagram+0x1b/0x100 net/core/datagram.c:329
 unix_dgram_recvmsg+0x8ae/0xef0 net/unix/af_unix.c:2191
 sock_recvmsg_nosec net/socket.c:795 [inline]
 sock_recvmsg net/socket.c:802 [inline]
 sock_recvmsg+0xce/0x110 net/socket.c:798
 __sys_recvfrom+0x1ff/0x350 net/socket.c:1844
 __do_sys_recvfrom net/socket.c:1862 [inline]
 __se_sys_recvfrom net/socket.c:1858 [inline]
 __x64_sys_recvfrom+0xe1/0x1a0 net/socket.c:1858
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff888096641340
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 320 bytes inside of
 512-byte region [ffff888096641340, ffff888096641540)
The buggy address belongs to the page:
page:ffffea0002599040 count:1 mapcount:0 mapping:ffff88812c31c940 index:0x0
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffffea00023131c8 ffffea0002605fc8 ffff88812c31c940
raw: 0000000000000000 ffff8880966410c0 0000000100000006 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888096641380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888096641400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888096641480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff888096641500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888096641580: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
==================================================================
kobject: 'kvm' (00000000a3f52244): kobject_uevent_env
kobject: 'kvm' (00000000a3f52244): fill_kobj_path: path = '/devices/virtual/misc/kvm'