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BUG: KASAN: stack-out-of-bounds in sys_fillrect+0x1f67/0x2570
Write of size 8 at addr ffffc90004eefbe0 by task syz.4.1430/9376

CPU: 0 UID: 0 PID: 9376 Comm: syz.4.1430 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 print_address_description+0x55/0x1e0
 print_report+0x58/0x70
 kasan_report+0x117/0x150
 sys_fillrect+0x1f67/0x2570
 drm_fbdev_shmem_defio_fillrect+0x2c/0x110
 bit_clear+0x168/0x200
 __fbcon_clear+0x9cd/0xd30
 fbcon_scroll+0x47e/0x7c0
 con_scroll+0x783/0xa10
 csi_ECMA+0x486/0x6850
 do_con_write+0x41ac/0x5500
 con_write+0x27/0x290
 n_tty_write+0xd49/0x11e0
 file_tty_write+0x509/0x9c0
 vfs_write+0x612/0xba0
 ksys_write+0x150/0x270
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe6bc59e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe6bd4ef028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fe6bc825fa0 RCX: 00007fe6bc59e0d9
RDX: 0000000000001006 RSI: 0000200000002100 RDI: 0000000000000004
RBP: 00007fe6bc635024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe6bc826038 R14: 00007fe6bc825fa0 R15: 00007fffca3955d8
 </TASK>

The buggy address belongs to a vmalloc virtual mapping
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x16bdb7
flags: 0x57ff00000000000(node=1|zone=2|lastcpupid=0x7ff)
raw: 057ff00000000000 0000000000000000 ffffea0005af6dc8 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x29c2(GFP_NOWAIT|__GFP_HIGHMEM|__GFP_IO|__GFP_FS|__GFP_ZERO), pid 2, tgid 2 (kthreadd), ts 54308535363
 post_alloc_hook+0x1f9/0x250
 get_page_from_freelist+0x2205/0x2280
 __alloc_frozen_pages_noprof+0x217/0x5a0
 __alloc_pages_noprof+0x10/0x100
 alloc_pages_node_noprof+0xe2/0x140
 __vmalloc_node_range_noprof+0x6d2/0x1540
 __vmalloc_node_noprof+0xc2/0x100
 dup_task_struct+0x2ae/0x8c0
 copy_process+0x820/0x4390
 kernel_clone+0x2d7/0x940
 kernel_thread+0x13f/0x1b0
 kthreadd+0x4ec/0x6e0
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
page last free pid 5359 tgid 5359 ts 29814798212 stack trace:
 __free_frozen_pages+0xc8f/0xd80
 __slab_free+0x274/0x2c0
 qlist_free_all+0x99/0x100
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_noprof+0x2a0/0x5f0
 do_getname+0x2e/0x250
 vfs_fstatat+0x45/0x170
 __x64_sys_newfstatat+0x151/0x200
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffffc90004eefa80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90004eefb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90004eefb80: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
                                                       ^
 ffffc90004eefc00: f8 f8 f8 f2 f2 f2 f2 f2 00 00 f3 f3 00 00 00 00
 ffffc90004eefc80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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