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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+0xbaf/0xd10 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffff8880a0a03410 by task syz-executor.1/13707

CPU: 0 PID: 13707 Comm: syz-executor.1 Not tainted 4.19.130-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 mm/kasan/report.c:412 [inline]
 __asan_report_load1_noabort+0x88/0x90 mm/kasan/report.c:430
 __fb_pad_aligned_buffer include/linux/fb.h:674 [inline]
 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline]
 bit_putcs+0xbaf/0xd10 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x336/0x4f0 drivers/video/fbdev/core/fbcon.c:1323
 con_flush drivers/tty/vt/vt.c:2552 [inline]
 do_con_write+0xbcd/0x1d90 drivers/tty/vt/vt.c:2802
 con_write+0x22/0xb0 drivers/tty/vt/vt.c:3138
 process_output_block drivers/tty/n_tty.c:593 [inline]
 n_tty_write+0x3c0/0xff0 drivers/tty/n_tty.c:2331
 do_tty_write drivers/tty/tty_io.c:960 [inline]
 tty_write+0x496/0x810 drivers/tty/tty_io.c:1044
 __vfs_write+0xf7/0x770 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: 0033:0x45cb29
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:00007fdc1aeeec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000050e120 RCX: 000000000045cb29
RDX: 0000000000000078 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000d2b R14: 00000000004cf870 R15: 00007fdc1aeef6d4

Allocated by task 5019:
 __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:4529 [inline]
 con_font_op+0xd02/0x10e0 drivers/tty/vt/vt.c:4594
 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 3620:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x210 mm/slab.c:3822
 kernfs_fop_release+0x120/0x190 fs/kernfs/file.c:783
 __fput+0x2ce/0x890 fs/file_table.c:278
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880a0a032c0
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 336 bytes inside of
 512-byte region [ffff8880a0a032c0, ffff8880a0a034c0)
The buggy address belongs to the page:
page:ffffea00028280c0 count:1 mapcount:0 mapping:ffff88812c39c940 index:0x0
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffffea000255c848 ffffea00027b8908 ffff88812c39c940
raw: 0000000000000000 ffff8880a0a03040 0000000100000006 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a0a03300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880a0a03380: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
>ffff8880a0a03400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff8880a0a03480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a0a03500: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
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