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BUG: KASAN: slab-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:674 [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+0xbaa/0xd10 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffff888084695140 by task syz-executor.0/28135

CPU: 1 PID: 28135 Comm: syz-executor.0 Not tainted 4.19.128-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+0x54/0x222 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+0x88/0x2b9 mm/kasan/report.c:396
 __fb_pad_aligned_buffer include/linux/fb.h:674 [inline]
 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline]
 bit_putcs+0xbaa/0xd10 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x424/0x4e0 drivers/video/fbdev/core/fbcon.c:1323
 con_flush drivers/tty/vt/vt.c:2552 [inline]
 do_con_write.part.0+0xf37/0x1db0 drivers/tty/vt/vt.c:2802
 do_con_write drivers/tty/vt/vt.c:2571 [inline]
 con_write+0x41/0xe0 drivers/tty/vt/vt.c:3138
 process_output_block drivers/tty/n_tty.c:593 [inline]
 n_tty_write+0x3ee/0x1080 drivers/tty/n_tty.c:2331
 do_tty_write drivers/tty/tty_io.c:960 [inline]
 tty_write+0x455/0x790 drivers/tty/tty_io.c:1044
 __vfs_write+0xf7/0x760 fs/read_write.c:485
 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
RIP: 0033:0x45ca69
Code: 0d b7 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb66bc02c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000050d440 RCX: 000000000045ca69
RDX: 0000000000000078 RSI: 0000000020000100 RDI: 0000000000000004
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000d09 R14: 00000000004cf610 R15: 00007fb66bc036d4

Allocated by task 22400:
 __do_kmalloc mm/slab.c:3727 [inline]
 __kmalloc+0x15a/0x3c0 mm/slab.c:3736
 kmalloc include/linux/slab.h:520 [inline]
 fbcon_set_font+0x331/0x870 drivers/video/fbdev/core/fbcon.c:2644
 con_font_set drivers/tty/vt/vt.c:4529 [inline]
 con_font_op+0xd3e/0x1130 drivers/tty/vt/vt.c:4594
 vt_ioctl+0xcd0/0x2500 drivers/tty/vt/vt_ioctl.c:928
 tty_ioctl+0x7a5/0x1420 drivers/tty/tty_io.c:2669
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcda/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 6725:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xce/0x220 mm/slab.c:3822
 kvfree+0x59/0x60 mm/util.c:452
 __do_replace+0x6a3/0x8a0 net/ipv6/netfilter/ip6_tables.c:1107
 do_replace net/ipv6/netfilter/ip6_tables.c:1160 [inline]
 do_ip6t_set_ctl+0x2d2/0x425 net/ipv6/netfilter/ip6_tables.c:1684
 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
 nf_setsockopt+0x6f/0xc0 net/netfilter/nf_sockopt.c:115
 ipv6_setsockopt net/ipv6/ipv6_sockglue.c:943 [inline]
 ipv6_setsockopt+0x13c/0x170 net/ipv6/ipv6_sockglue.c:927
 tcp_setsockopt net/ipv4/tcp.c:3095 [inline]
 tcp_setsockopt+0x86/0xd0 net/ipv4/tcp.c:3089
 __sys_setsockopt+0x14d/0x240 net/socket.c:1901
 __do_sys_setsockopt net/socket.c:1912 [inline]
 __se_sys_setsockopt net/socket.c:1909 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:1909
 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 ffff888084694d80
 which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 960 bytes inside of
 1024-byte region [ffff888084694d80, ffff888084695180)
The buggy address belongs to the page:
page:ffffea000211a500 count:1 mapcount:0 mapping:ffff88812c3dcac0 index:0xffff888084694480 compound_mapcount: 0
flags: 0xfffe0000008100(slab|head)
raw: 00fffe0000008100 ffffea00025b6788 ffffea0002a36988 ffff88812c3dcac0
raw: ffff888084694480 ffff888084694000 0000000100000006 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888084695000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888084695080: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888084695100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                           ^
 ffff888084695180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888084695200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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