BUG: sleeping function called from invalid context at kernel/sched/completion.c:111
==================================================================
BUG: KASAN: out-of-bounds in user_mode arch/x86/include/asm/ptrace.h:214 [inline]
BUG: KASAN: out-of-bounds in kernelmode_fixup_or_oops+0xe0/0xf0 arch/x86/mm/fault.c:725
Read of size 2 at addr ffffc90003ff6ef0 by task syz.0.19/5400

CPU: 0 UID: 0 PID: 5400 Comm: syz.0.19 Not tainted 6.11.0-rc4-next-20240820-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
 </TASK>

The buggy address belongs to stack of task syz.0.19/5400

The buggy address belongs to the virtual mapping at
 [ffffc90003ff0000, ffffc90003ff9000) created by:
 copy_process+0x5d1/0x3d50 kernel/fork.c:2206

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4ea05
memcg:ffff88802d5c4b82
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff ffff88802d5c4b82
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 5313, tgid 5313 (syz.3.4), ts 60567098081, free_ts 60112152535
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1517
 prep_new_page mm/page_alloc.c:1525 [inline]
 get_page_from_freelist+0x3004/0x30c0 mm/page_alloc.c:3476
 __alloc_pages_noprof+0x29e/0x780 mm/page_alloc.c:4743
 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:2206
 kernel_clone+0x226/0x8f0 kernel/fork.c:2787
 __do_sys_clone3 kernel/fork.c:3091 [inline]
 __se_sys_clone3+0x2cb/0x350 kernel/fork.c:3070
 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 5230 tgid 5230 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1098 [inline]
 free_unref_page+0xc07/0xd90 mm/page_alloc.c:2651
 discard_slab mm/slub.c:2630 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3098
 put_cpu_partial+0x17c/0x250 mm/slub.c:3173
 __slab_free+0x2ea/0x3d0 mm/slub.c:4391
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4036 [inline]
 slab_alloc_node mm/slub.c:4085 [inline]
 kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4092
 getname_flags+0xb7/0x540 fs/namei.c:139
 user_path_at+0x24/0x60 fs/namei.c:3015
 __do_sys_pivot_root fs/namespace.c:4347 [inline]
 __se_sys_pivot_root+0x180/0x1650 fs/namespace.c:4336
 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

Memory state around the buggy address:
 ffffc90003ff6d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90003ff6e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90003ff6e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                                ^
 ffffc90003ff6f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90003ff6f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================