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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 8 at addr ffff888083cd5b10 by task syz-executor.1/25642

CPU: 0 PID: 25642 Comm: syz-executor.1 Not tainted 4.19.138-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: 0033:0x45ce79
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:00007fe55d685c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000000f600 RCX: 000000000045ce79
RDX: 0000000020000000 RSI: 0000000000004b72 RDI: 0000000000000005
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007fff3ee5608f R14: 00007fe55d6869c0 R15: 000000000118bf2c

Allocated by task 1112:
 __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 6466:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x210 mm/slab.c:3822
 skb_free_head net/core/skbuff.c:554 [inline]
 skb_release_data+0x6de/0x920 net/core/skbuff.c:574
 skb_release_all net/core/skbuff.c:631 [inline]
 __kfree_skb net/core/skbuff.c:645 [inline]
 consume_skb+0x113/0x3d0 net/core/skbuff.c:705
 __dev_kfree_skb_any+0x9c/0xc0 net/core/dev.c:2796
 dev_consume_skb_any include/linux/netdevice.h:3557 [inline]
 napi_consume_skb+0x45d/0x5e0 net/core/skbuff.c:769
 free_old_xmit_skbs+0xdb/0x240 drivers/net/virtio_net.c:1379
 start_xmit+0x15a/0x16e0 drivers/net/virtio_net.c:1575
 __netdev_start_xmit include/linux/netdevice.h:4333 [inline]
 netdev_start_xmit include/linux/netdevice.h:4347 [inline]
 xmit_one net/core/dev.c:3256 [inline]
 dev_hard_start_xmit+0x1a8/0x920 net/core/dev.c:3272
 sch_direct_xmit+0x2d6/0xf50 net/sched/sch_generic.c:332
 qdisc_restart net/sched/sch_generic.c:395 [inline]
 __qdisc_run+0x4d0/0x1630 net/sched/sch_generic.c:403
 qdisc_run include/net/pkt_sched.h:120 [inline]
 __dev_xmit_skb net/core/dev.c:3451 [inline]
 __dev_queue_xmit+0x2102/0x2e00 net/core/dev.c:3807
 neigh_hh_output include/net/neighbour.h:491 [inline]
 neigh_output include/net/neighbour.h:499 [inline]
 ip_finish_output2+0xb6d/0x1540 net/ipv4/ip_output.c:229
 ip_finish_output+0x84d/0xcd0 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip_output+0x203/0x5f0 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:455 [inline]
 ip_local_out+0xaf/0x170 net/ipv4/ip_output.c:124
 __ip_queue_xmit+0x866/0x1b50 net/ipv4/ip_output.c:505
 __tcp_transmit_skb+0x1bb2/0x33f0 net/ipv4/tcp_output.c:1148
 tcp_transmit_skb net/ipv4/tcp_output.c:1164 [inline]
 tcp_write_xmit+0x968/0x4fb0 net/ipv4/tcp_output.c:2389
 __tcp_push_pending_frames+0xae/0x280 net/ipv4/tcp_output.c:2568
 tcp_push+0x4b7/0x6b0 net/ipv4/tcp.c:743
 tcp_sendmsg_locked+0x26a9/0x2f60 net/ipv4/tcp.c:1430
 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1460
 inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:632
 sock_write_iter+0x287/0x3c0 net/socket.c:901
 call_write_iter include/linux/fs.h:1821 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x51b/0x770 fs/read_write.c:487
 vfs_write+0x1f3/0x540 fs/read_write.c:549
 ksys_write+0x12b/0x2a0 fs/read_write.c:599
 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 ffff888083cd5600
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 1296 bytes inside of
 2048-byte region [ffff888083cd5600, ffff888083cd5e00)
The buggy address belongs to the page:
page:ffffea00020f3500 count:1 mapcount:0 mapping:ffff88812c39cc40 index:0x0 compound_mapcount: 0
flags: 0xfffe0000008100(slab|head)
raw: 00fffe0000008100 ffffea0002433708 ffffea0001621788 ffff88812c39cc40
raw: 0000000000000000 ffff888083cd4500 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888083cd5a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888083cd5a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888083cd5b00: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff888083cd5b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888083cd5c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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