BUG: kernel NULL pointer dereference, address: 0000000000000dc0
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 800000004c293067 P4D 800000004c293067 PUD 7b042067 PMD 0 
Oops: Oops: 0010 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 5494 Comm: syz.0.49 Not tainted 6.11.0-rc5-next-20240827-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:0xdc0
Code: Unable to access opcode bytes at 0xd96.
RSP: 0018:ffffc90009187818 EFLAGS: 00010046
==================================================================
BUG: KASAN: stack-out-of-bounds in __show_regs+0xdc/0x610 arch/x86/kernel/process_64.c:83
Read of size 8 at addr ffffc900091877c0 by task syz.0.49/5494

CPU: 1 UID: 0 PID: 5494 Comm: syz.0.49 Not tainted 6.11.0-rc5-next-20240827-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 __show_regs+0xdc/0x610 arch/x86/kernel/process_64.c:83
 show_regs arch/x86/kernel/dumpstack.c:472 [inline]
 __die_body+0x3c/0xb0 arch/x86/kernel/dumpstack.c:420
 page_fault_oops+0x8e4/0xcc0 arch/x86/mm/fault.c:711
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x5ed/0x8c0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:0xdc0
Code: Unable to access opcode bytes at 0xd96.
RSP: 0018:ffffc90009187818 EFLAGS: 00010046
RAX: 962f36debd9e6000 RBX: dffffc0000000000 RCX: ffffc90009187703
RDX: 0000000000000005 RSI: ffffffff8c0adc40 RDI: ffffffff8c6088c0
RBP: ffff8880166f9280 R08: ffffffff901c362f R09: 1ffffffff20386c5
R10: dffffc0000000000 R11: fffffbfff20386c6 R12: 962f36debd9e6000
R13: 0000000000000006 R14: ffffffff8205dbd9 R15: 0000000000000001
 </TASK>

The buggy address belongs to stack of task syz.0.49/5494
 and is located at offset 512 in frame:
 page_fault_oops+0x0/0xcc0

This frame has 7 objects:
 [32, 36) 'level.i'
 [48, 49) 'nx.i'
 [64, 65) 'rw.i'
 [80, 90) 'idt.i'
 [112, 122) 'gdt.i'
 [144, 146) 'ldtr.i'
 [160, 192) 'info'

The buggy address belongs to the virtual mapping at
 [ffffc90009180000, ffffc90009189000) created by:
 copy_process+0x5d1/0x3d50 kernel/fork.c:2203

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88804cc30d80 pfn:0x4cc30
memcg:ffff8880236a6e82
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: ffff88804cc30d80 0000000000000000 00000001ffffffff ffff8880236a6e82
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 5491, tgid 5491 (syz.0.49), ts 96548238007, free_ts 94253638483
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1520
 prep_new_page mm/page_alloc.c:1528 [inline]
 get_page_from_freelist+0x312a/0x3270 mm/page_alloc.c:3479
 __alloc_pages_noprof+0x29e/0x780 mm/page_alloc.c:4751
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 vm_area_alloc_pages mm/vmalloc.c:3600 [inline]
 __vmalloc_area_node mm/vmalloc.c:3669 [inline]
 __vmalloc_node_range_noprof+0xa40/0x1400 mm/vmalloc.c:3850
 alloc_thread_stack_node kernel/fork.c:314 [inline]
 dup_task_struct+0x444/0x8c0 kernel/fork.c:1115
 copy_process+0x5d1/0x3d50 kernel/fork.c:2203
 kernel_clone+0x226/0x8f0 kernel/fork.c:2784
 __do_sys_clone3 kernel/fork.c:3088 [inline]
 __se_sys_clone3+0x2cb/0x350 kernel/fork.c:3067
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5281 tgid 5281 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1101 [inline]
 free_unref_page+0xc64/0xe80 mm/page_alloc.c:2654
 vfree+0x186/0x2e0 mm/vmalloc.c:3380
 delayed_vfree_work+0x56/0x80 mm/vmalloc.c:3301
 process_one_work kernel/workqueue.c:3232 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3313
 worker_thread+0x86d/0xd10 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffffc90009187680: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90009187700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90009187780: 00 00 00 00 00 00 00 00 f3 f3 f3 f3 00 00 00 00
                                           ^
 ffffc90009187800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90009187880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================