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BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:372 [inline]
BUG: KASAN: slab-out-of-bounds in soft_cursor+0x442/0xa50 drivers/video/fbdev/core/softcursor.c:70
Read of size 32 at addr ffff888091212d50 by task syz-executor.0/27643

CPU: 1 PID: 27643 Comm: syz-executor.0 Not tainted 4.14.204-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+0x1b2/0x283 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351
 kasan_report+0x6f/0x7b mm/kasan/report.c:409
 memcpy+0x20/0x50 mm/kasan/kasan.c:302
 memcpy include/linux/string.h:372 [inline]
 soft_cursor+0x442/0xa50 drivers/video/fbdev/core/softcursor.c:70
 bit_cursor+0xf7a/0x1580 drivers/video/fbdev/core/bitblit.c:377
 fbcon_cursor+0x480/0x640 drivers/video/fbdev/core/fbcon.c:1287
 hide_cursor+0x7a/0x2a0 drivers/tty/vt/vt.c:590
 redraw_screen+0x29d/0x790 drivers/tty/vt/vt.c:680
 fbcon_do_set_font+0x62a/0x800 drivers/video/fbdev/core/fbcon.c:2399
 fbcon_copy_font+0x125/0x190 drivers/video/fbdev/core/fbcon.c:2414
 con_font_copy drivers/tty/vt/vt.c:4246 [inline]
 con_font_op+0x58b/0xf60 drivers/tty/vt/vt.c:4261
 vt_ioctl+0x113d/0x1d50 drivers/tty/vt/vt_ioctl.c:990
 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
RIP: 0033:0x45deb9
RSP: 002b:00007f519b280c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000000108c0 RCX: 000000000045deb9
RDX: 0000000020000080 RSI: 0000000000004b72 RDI: 0000000000000004
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007ffd8b661e8f R14: 00007f519b2819c0 R15: 000000000118bf2c

Allocated by task 27095:
 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:2456
 con_font_set drivers/tty/vt/vt.c:4190 [inline]
 con_font_op+0xb69/0xf60 drivers/tty/vt/vt.c:4255
 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 25641:
 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:554 [inline]
 skb_release_data+0x5f6/0x820 net/core/skbuff.c:574
 skb_release_all net/core/skbuff.c:631 [inline]
 __kfree_skb net/core/skbuff.c:645 [inline]
 consume_skb+0xe0/0x380 net/core/skbuff.c:705
 skb_free_datagram+0x16/0xe0 net/core/datagram.c:331
 netlink_recvmsg+0x5c1/0xda0 net/netlink/af_netlink.c:1957
 sock_recvmsg_nosec net/socket.c:819 [inline]
 sock_recvmsg net/socket.c:826 [inline]
 sock_recvmsg net/socket.c:822 [inline]
 SYSC_recvfrom net/socket.c:1815 [inline]
 SyS_recvfrom+0x21b/0x340 net/socket.c:1787
 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 ffff888091212940
 which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 16 bytes to the right of
 1024-byte region [ffff888091212940, ffff888091212d40)
The buggy address belongs to the page:
page:ffffea0002448480 count:1 mapcount:0 mapping:ffff888091212040 index:0xffff8880912124c0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffff888091212040 ffff8880912124c0 0000000100000003
raw: ffffea0002953f20 ffffea00024d7aa0 ffff88813fe80ac0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888091212c00: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
 ffff888091212c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888091212d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                 ^
 ffff888091212d80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff888091212e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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