diff options
| author | Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | 2022-12-15 14:46:21 -0500 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-12-21 14:31:51 -0800 |
| commit | 38ce7c9bdfc228c14d7621ba36d3eebedd9d4f76 (patch) | |
| tree | 698c4511f0ca0cfd5168a0b55052d2d5a252ef7c /mm | |
| parent | 6f12be792fde994ed934168f93c2a0d2a0cf0bc5 (diff) | |
mm/mempolicy: fix memory leak in set_mempolicy_home_node system call
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: c6018b4b2549 ("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>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/mempolicy.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 61aa9aedb728..02c8a712282f 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1540,6 +1540,7 @@ SYSCALL_DEFINE4(set_mempolicy_home_node, unsigned long, start, unsigned long, le * the home node for vmas we already updated before. */ if (new->mode != MPOL_BIND && new->mode != MPOL_PREFERRED_MANY) { + mpol_put(new); err = -EOPNOTSUPP; break; } |