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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+0x103a/0x1bf0 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffff88809e01b484 by task syz-executor.0/5083

CPU: 1 PID: 5083 Comm: syz-executor.0 Not tainted 5.9.0-rc7-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+0x1d6/0x29e lib/dump_stack.c:118
 print_address_description+0x66/0x620 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report+0x132/0x1d0 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+0x103a/0x1bf0 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x790/0xaf0 drivers/video/fbdev/core/fbcon.c:1308
 con_flush drivers/tty/vt/vt.c:2575 [inline]
 do_con_write+0xd42b/0xd580 drivers/tty/vt/vt.c:2916
 con_write+0x20/0x40 drivers/tty/vt/vt.c:3250
 process_output_block drivers/tty/n_tty.c:595 [inline]
 n_tty_write+0xcbf/0x1170 drivers/tty/n_tty.c:2333
 do_tty_write drivers/tty/tty_io.c:962 [inline]
 tty_write+0x593/0x940 drivers/tty/tty_io.c:1046
 do_loop_readv_writev fs/read_write.c:745 [inline]
 do_iter_write+0x441/0x610 fs/read_write.c:1028
 vfs_writev fs/read_write.c:1099 [inline]
 do_writev+0x23f/0x4a0 fs/read_write.c:1142
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45dd99
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:00007fa48df06c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 000000000003a680 RCX: 000000000045dd99
RDX: 0000000000000001 RSI: 00000000200005c0 RDI: 0000000000000005
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007ffe3af9fd5f R14: 00007fa48df079c0 R15: 000000000118bf2c

Allocated by task 12370:
 kasan_save_stack mm/kasan/common.c:48 [inline]
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc+0x100/0x130 mm/kasan/common.c:461
 __do_kmalloc mm/slab.c:3659 [inline]
 __kmalloc+0x205/0x300 mm/slab.c:3668
 kmalloc include/linux/slab.h:559 [inline]
 fbcon_set_font+0x2c4/0x970 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4663 [inline]
 con_font_op+0xebc/0x1630 drivers/tty/vt/vt.c:4728
 vt_io_ioctl drivers/tty/vt/vt_ioctl.c:506 [inline]
 vt_ioctl+0xd7f/0x3d70 drivers/tty/vt/vt_ioctl.c:856
 tty_ioctl+0xee4/0x15c0 drivers/tty/tty_io.c:2656
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:739
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Last call_rcu():
 kasan_save_stack+0x27/0x50 mm/kasan/common.c:48
 kasan_record_aux_stack+0x7b/0xb0 mm/kasan/generic.c:346
 __call_rcu kernel/rcu/tree.c:2896 [inline]
 call_rcu+0x141/0x830 kernel/rcu/tree.c:2970
 _free_event+0xe5d/0x11c0 kernel/events/core.c:4831
 put_event kernel/events/core.c:4906 [inline]
 perf_event_release_kernel+0xbd7/0xc90 kernel/events/core.c:5021
 perf_release+0x37/0x40 kernel/events/core.c:5031
 __fput+0x34f/0x7b0 fs/file_table.c:281
 task_work_run+0x137/0x1c0 kernel/task_work.c:141
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:165 [inline]
 exit_to_user_mode_prepare+0x11a/0x1e0 kernel/entry/common.c:192
 syscall_exit_to_user_mode+0x82/0x1d0 kernel/entry/common.c:267
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88809e01b000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1156 bytes inside of
 2048-byte region [ffff88809e01b000, ffff88809e01b800)
The buggy address belongs to the page:
page:00000000ed1d01ea refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9e01b
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea00028aaec8 ffffea00027d5c48 ffff8880aa440800
raw: 0000000000000000 ffff88809e01b000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809e01b380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88809e01b400: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88809e01b480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88809e01b500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88809e01b580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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