selftests/mm: fix BUG_ON checking wrong variable in mremap_dontunmap

In mremap_dontunmap_partial_mapping_overwrite(), mremap() stores its
returned remapped address into remapped_mapping, while the BUG_ON
incorrectly checks dest_mapping instead.

If mremap() fails, dest_mapping still holds a valid pointer obtained from
the prior mmap() call, making this BUG_ON never trigger at all.  Correct
the check to validate the actual mremap() return value stored in
remapped_mapping.

Link: https://lore.kernel.org/20260717070251.73212-1-hongfu.li@linux.dev
Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
Reviewed-by: SJ Park <sj@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

0 files changed, 0 insertions, 0 deletions