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BUG: KASAN: slab-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:656 [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+0x132a/0x1bf0 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffff888053424d70 by task syz-executor.2/4850

CPU: 1 PID: 4850 Comm: syz-executor.2 Not tainted 5.8.0-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+0x1f0/0x31e 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:656 [inline]
 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline]
 bit_putcs+0x132a/0x1bf0 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x790/0xaf0 drivers/video/fbdev/core/fbcon.c:1362
 do_update_region+0x462/0x620 drivers/tty/vt/vt.c:675
 redraw_screen+0xa25/0x1420 drivers/tty/vt/vt.c:1034
 fbcon_modechanged+0x8d5/0xd90 drivers/video/fbdev/core/fbcon.c:3001
 fb_set_var+0x825/0xcc0 drivers/video/fbdev/core/fbmem.c:1056
 do_fb_ioctl+0x502/0x6f0 drivers/video/fbdev/core/fbmem.c:1109
 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
RIP: 0033:0x45d189
Code: 5d 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 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f98f56fdc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000000d580 RCX: 000000000045d189
RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffc9a08ca6f R14: 00007f98f56fe9c0 R15: 000000000118cf4c

Allocated by task 31206:
 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:3655 [inline]
 __kmalloc+0x218/0x320 mm/slab.c:3664
 kmalloc include/linux/slab.h:559 [inline]
 fbcon_set_font+0x2c4/0x970 drivers/video/fbdev/core/fbcon.c:2673
 con_font_set drivers/tty/vt/vt.c:4662 [inline]
 con_font_op+0xebc/0x1630 drivers/tty/vt/vt.c:4727
 vt_io_ioctl drivers/tty/vt/vt_ioctl.c:506 [inline]
 vt_ioctl+0xd7f/0x3c60 drivers/tty/vt/vt_ioctl.c:846
 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

The buggy address belongs to the object at ffff888053424000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 3440 bytes inside of
 4096-byte region [ffff888053424000, ffff888053425000)
The buggy address belongs to the page:
page:00000000c2f032c6 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x53424
head:00000000c2f032c6 order:1 compound_mapcount:0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea000241b208 ffffea00011e0e08 ffff8880aa440900
raw: 0000000000000000 ffff888053424000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888053424c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888053424c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888053424d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                             ^
 ffff888053424d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888053424e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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