+ lib-group_cpus-handle-const-qualifier-from-clusters-allocation-type.patch added to mm-nonmm-unstable branch

+ lib-group_cpus-handle-const-qualifier-from-clusters-allocation-type.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: lib/group_cpus: handle const qualifier from clusters allocation type
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     lib-group_cpus-handle-const-qualifier-from-clusters-allocation-type.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-group_cpus-handle-const-qualifier-from-clusters-allocation-type.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Kees Cook <kees@kernel.org>
Subject: lib/group_cpus: handle const qualifier from clusters allocation type
Date: Fri, 6 Feb 2026 14:20:13 -0800

In preparation for making the kmalloc family of allocators type aware, we
need to make sure that the returned type from the allocation matches the
type of the variable being assigned.  (Before, the allocator would always
return "void *", which can be implicitly cast to any pointer type.)

The assigned type is "const struct cpumask **", but the returned type,
while matching, is not const qualified.  To get them exactly matching,
just use the dereferenced pointer for the sizeof().

Link: https://lkml.kernel.org/r/20260206222010.work.349-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
Cc: Wangyang Guo <wangyang.guo@intel.com>
Cc: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/group_cpus.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/lib/group_cpus.c~lib-group_cpus-handle-const-qualifier-from-clusters-allocation-type
+++ a/lib/group_cpus.c
@@ -320,7 +320,7 @@ static int alloc_cluster_groups(unsigned
 		goto no_cluster;
 
 	/* Allocate memory based on cluster number. */
-	clusters = kcalloc(ncluster, sizeof(struct cpumask *), GFP_KERNEL);
+	clusters = kcalloc(ncluster, sizeof(*clusters), GFP_KERNEL);
 	if (!clusters)
 		goto no_cluster;
 	cluster_groups = kcalloc(ncluster, sizeof(struct node_groups), GFP_KERNEL);
_

Patches currently in -mm which might be from kees@kernel.org are

lib-group_cpus-handle-const-qualifier-from-clusters-allocation-type.patch