This is a note to let you know that I've just added the patch titled
mm/mempolicy: fix memory leak in set_mempolicy_home_node system call
to the 6.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-mempolicy-fix-memory-leak-in-set_mempolicy_home_node-system-call.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 38ce7c9bdfc228c14d7621ba36d3eebedd9d4f76 Mon Sep 17 00:00:00 2001
From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Date: Thu, 15 Dec 2022 14:46:21 -0500
Subject: mm/mempolicy: fix memory leak in set_mempolicy_home_node system call
From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
commit 38ce7c9bdfc228c14d7621ba36d3eebedd9d4f76 upstream.
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@xxxxxxxxxxxx
Fixes: c6018b4b2549 ("mm/mempolicy: add set_mempolicy_home_node syscall")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Reviewed-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Reviewed-by: "Huang, Ying" <ying.huang@xxxxxxxxx>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Cc: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Feng Tang <feng.tang@xxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Huang Ying <ying.huang@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> [5.17+]
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
mm/mempolicy.c | 1 +
1 file changed, 1 insertion(+)
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1525,6 +1525,7 @@ SYSCALL_DEFINE4(set_mempolicy_home_node,
* 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;
}
Patches currently in stable-queue which might be from mathieu.desnoyers@xxxxxxxxxxxx are
queue-6.0/futex-fix-futex_waitv-hrtimer-debug-object-leak-on-kcalloc-error.patch
queue-6.0/mm-mempolicy-fix-memory-leak-in-set_mempolicy_home_node-system-call.patch
