mm/mempolicy: fix memory leak in set_mempolicy_home_node system call

mainline inclusion
from mainline-v6.2-rc1
commit 38ce7c9b
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I6I1Z2
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=38ce7c9bdfc228c14d7621ba36d3eebedd9d4f76

--------------------------------

When encountering any vma in the range with policy other than MPOL_BIND or
MPOL_PREFERRED_MANY, an error is returned without issuing a mpol_put on
the policy just allocated with mpol_dup().

This allows arbitrary users to leak kernel memory.

Link: https://lkml.kernel.org/r/20221215194621.202816-1-mathieu.desnoyers@efficios.com


Fixes: c6018b4b ("mm/mempolicy: add set_mempolicy_home_node syscall")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: <stable@vger.kernel.org>	[5.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>