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BUG: KASAN: slab-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:654 [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+0xbb6/0xd20 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffff8880946acabc by task syz-executor.3/13198

CPU: 0 PID: 13198 Comm: syz-executor.3 Not tainted 5.9.0-rc8-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+0x198/0x1fd lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 __fb_pad_aligned_buffer include/linux/fb.h:654 [inline]
 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline]
 bit_putcs+0xbb6/0xd20 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x35a/0x450 drivers/video/fbdev/core/fbcon.c:1308
 con_flush drivers/tty/vt/vt.c:2575 [inline]
 do_con_write+0xb6b/0x1dd0 drivers/tty/vt/vt.c:2905
 con_write+0x22/0xb0 drivers/tty/vt/vt.c:3250
 n_tty_write+0xa38/0xf80 drivers/tty/n_tty.c:2356
 do_tty_write drivers/tty/tty_io.c:962 [inline]
 tty_write+0x4d9/0x870 drivers/tty/tty_io.c:1046
 __kernel_write+0x199/0x570 fs/read_write.c:528
 write_pipe_buf+0x153/0x1f0 fs/splice.c:819
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x3dc/0x830 fs/splice.c:646
 splice_from_pipe fs/splice.c:681 [inline]
 default_file_splice_write fs/splice.c:831 [inline]
 do_splice_from fs/splice.c:867 [inline]
 direct_splice_actor+0x228/0x2f0 fs/splice.c:1036
 splice_direct_to_actor+0x38c/0x980 fs/splice.c:991
 do_splice_direct+0x1b3/0x280 fs/splice.c:1079
 do_sendfile+0x55f/0xd40 fs/read_write.c:1548
 __do_sys_sendfile64 fs/read_write.c:1609 [inline]
 __se_sys_sendfile64 fs/read_write.c:1595 [inline]
 __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1595
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45de29
Code: 0d b4 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 b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f88ee9e9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000027ec0 RCX: 000000000045de29
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000004
RBP: 000000000118bf68 R08: 0000000000000000 R09: 0000000000000000
R10: 0800000080004103 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007ffc75a9673f R14: 00007f88ee9ea9c0 R15: 000000000118bf2c

Allocated by task 9040:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461
 __do_kmalloc mm/slab.c:3659 [inline]
 __kmalloc+0x1b0/0x360 mm/slab.c:3668
 kmalloc include/linux/slab.h:559 [inline]
 fbcon_set_font+0x363/0x9b0 drivers/video/fbdev/core/fbcon.c:2508
 con_font_set drivers/tty/vt/vt.c:4663 [inline]
 con_font_op+0xd26/0x1140 drivers/tty/vt/vt.c:4728
 vt_io_ioctl drivers/tty/vt/vt_ioctl.c:595 [inline]
 vt_ioctl+0x1ce7/0x2e90 drivers/tty/vt/vt_ioctl.c:856
 tty_ioctl+0x1019/0x15f0 drivers/tty/tty_io.c:2656
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff8880946ac800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 700 bytes inside of
 1024-byte region [ffff8880946ac800, ffff8880946acc00)
The buggy address belongs to the page:
page:000000006e71f850 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x946ac
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea00027d9f48 ffffea0002534f88 ffff8880aa040700
raw: 0000000000000000 ffff8880946ac000 0000000100000002 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880946ac980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880946aca00: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880946aca80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                        ^
 ffff8880946acb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880946acb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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