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BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:348 [inline]
BUG: KASAN: slab-out-of-bounds in fbcon_get_font+0x2b2/0x5e0 drivers/video/fbdev/core/fbcon.c:2443
Read of size 8 at addr ffff8880a419e8d0 by task syz-executor.4/13346

CPU: 1 PID: 13346 Comm: syz-executor.4 Not tainted 4.19.89-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
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x123/0x190 mm/kasan/kasan.c:267
 memcpy+0x24/0x50 mm/kasan/kasan.c:302
 memcpy include/linux/string.h:348 [inline]
 fbcon_get_font+0x2b2/0x5e0 drivers/video/fbdev/core/fbcon.c:2443
 con_font_get drivers/tty/vt/vt.c:4400 [inline]
 con_font_op+0x20b/0x1250 drivers/tty/vt/vt.c:4559
 vt_ioctl+0xd2e/0x2530 drivers/tty/vt/vt_ioctl.c:913
 tty_ioctl+0x7f3/0x1510 drivers/tty/tty_io.c:2669
 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
RIP: 0033:0x45a909
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:00007f7f20ab7c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a909
RDX: 0000000020000000 RSI: 0000000000004b60 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7f20ab86d4
R13: 00000000004c7019 R14: 00000000004dd688 R15: 00000000ffffffff

Allocated by task 10614:
 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]
 fbcon_set_font+0x32d/0x860 drivers/video/fbdev/core/fbcon.c:2641
 con_font_set drivers/tty/vt/vt.c:4492 [inline]
 con_font_op+0xe18/0x1250 drivers/tty/vt/vt.c:4557
 vt_ioctl+0xd2e/0x2530 drivers/tty/vt/vt_ioctl.c:913
 tty_ioctl+0x7f3/0x1510 drivers/tty/tty_io.c:2669
 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 8564:
 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+0x16/0x30 net/core/skbuff.c:645
 sk_wmem_free_skb include/net/sock.h:1457 [inline]
 tcp_rtx_queue_unlink_and_free include/net/tcp.h:1740 [inline]
 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3148 [inline]
 tcp_ack+0x1e42/0x5120 net/ipv4/tcp_input.c:3673
 tcp_rcv_state_process+0xc6e/0x4e68 net/ipv4/tcp_input.c:6065
 tcp_v6_do_rcv+0x894/0x13c0 net/ipv6/tcp_ipv6.c:1352
 sk_backlog_rcv include/net/sock.h:941 [inline]
 __release_sock+0x129/0x390 net/core/sock.c:2339
 __sk_flush_backlog+0x28/0x40 net/core/sock.c:2359
 sk_flush_backlog include/net/sock.h:1028 [inline]
 tcp_sendmsg_locked+0x27da/0x3260 net/ipv4/tcp.c:1297
 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1454
 inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 __sys_sendto+0x262/0x380 net/socket.c:1787
 __do_sys_sendto net/socket.c:1799 [inline]
 __se_sys_sendto net/socket.c:1795 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1795
 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 ffff8880a419e1c0
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 1808 bytes inside of
 2048-byte region [ffff8880a419e1c0, ffff8880a419e9c0)
The buggy address belongs to the page:
page:ffffea0002906780 count:1 mapcount:0 mapping:ffff88812c31cc40 index:0x0 compound_mapcount: 0
flags: 0xfffe0000008100(slab|head)
raw: 00fffe0000008100 ffffea00026b2708 ffffea0001542408 ffff88812c31cc40
raw: 0000000000000000 ffff8880a419e1c0 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a419e780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880a419e800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880a419e880: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
                                                 ^
 ffff8880a419e900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a419e980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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