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BUG: KASAN: slab-out-of-bounds in walk_stackframe+0x11c/0x260 arch/riscv/kernel/stacktrace.c:57
Read of size 8 at addr ffffaf802138bff0 by task syz-executor.0/2051

CPU: 0 PID: 2051 Comm: syz-executor.0 Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff8000a228>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:113
[<ffffffff831668cc>] show_stack+0x34/0x40 arch/riscv/kernel/stacktrace.c:119
[<ffffffff831756ba>] __dump_stack lib/dump_stack.c:88 [inline]
[<ffffffff831756ba>] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:106
[<ffffffff8047479e>] print_address_description.constprop.0+0x2a/0x330 mm/kasan/report.c:255
[<ffffffff80474d4c>] __kasan_report mm/kasan/report.c:442 [inline]
[<ffffffff80474d4c>] kasan_report+0x184/0x1e0 mm/kasan/report.c:459
[<ffffffff80475b20>] check_region_inline mm/kasan/generic.c:183 [inline]
[<ffffffff80475b20>] __asan_load8+0x6e/0x96 mm/kasan/generic.c:256
[<ffffffff8000a052>] walk_stackframe+0x11c/0x260 arch/riscv/kernel/stacktrace.c:57
[<ffffffff8000a4a4>] arch_stack_walk+0x2c/0x3c arch/riscv/kernel/stacktrace.c:146

Allocated by task 0:
(stack is not available)

The buggy address belongs to the object at ffffaf802138be00
 which belongs to the cache mnt_cache of size 320
The buggy address is located 176 bytes to the right of
 320-byte region [ffffaf802138be00, ffffaf802138bf40)
The buggy address belongs to the page:
page:ffffaf807afa0ed0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xa158a
head:ffffaf807afa0ed0 order:1 compound_mapcount:0
flags: 0xa000010200(slab|head|section=20|node=0|zone=0)
raw: 000000a000010200 0000000000000000 0000000000000122 ffffaf80072ed140
raw: 0000000000000000 0000000080150015 00000001ffffffff 0000000000000000
raw: 00000000000007ff
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2051, ts 1116480958600, free_ts 0
 __set_page_owner+0x48/0x136 mm/page_owner.c:183
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0xd0/0x10a mm/page_alloc.c:2427
 prep_new_page mm/page_alloc.c:2434 [inline]
 get_page_from_freelist+0x8da/0x12d8 mm/page_alloc.c:4165
 __alloc_pages+0x150/0x3b6 mm/page_alloc.c:5389
 alloc_pages+0x132/0x2a6 mm/mempolicy.c:2271
 alloc_slab_page.constprop.0+0xc2/0xfa mm/slub.c:1799
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x25a/0x2cc mm/slub.c:2004
 ___slab_alloc+0x56e/0x918 mm/slub.c:3018
 __slab_alloc.constprop.0+0x50/0x8c mm/slub.c:3105
 slab_alloc_node mm/slub.c:3196 [inline]
 slab_alloc mm/slub.c:3238 [inline]
 kmem_cache_alloc+0x39c/0x3de mm/slub.c:3243
 kmem_cache_zalloc include/linux/slab.h:705 [inline]
 alloc_vfsmnt+0x32/0x2ea fs/namespace.c:198
 clone_mnt+0x4a/0x75a fs/namespace.c:1061
 copy_tree+0x2bc/0x6c8 fs/namespace.c:1878
 copy_mnt_ns+0x174/0x71c fs/namespace.c:3434
 create_new_namespaces+0xac/0x6f8 kernel/nsproxy.c:78
 unshare_nsproxy_namespaces+0xa2/0x144 kernel/nsproxy.c:226
page_owner free stack trace missing

Memory state around the buggy address:
 ffffaf802138be80: fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00 00
 ffffaf802138bf00: fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00 00
>ffffaf802138bf80: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
                                                             ^
 ffffaf802138c000: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 f3
 ffffaf802138c080: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
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