+ selftests-cgroup-test_zswap-check-malloc-return-value.patch added to mm-unstable branch

+ selftests-cgroup-test_zswap-check-malloc-return-value.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: selftests/cgroup: test_zswap: check malloc() return value
has been added to the -mm mm-unstable branch.  Its filename is
     selftests-cgroup-test_zswap-check-malloc-return-value.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-cgroup-test_zswap-check-malloc-return-value.patch

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

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------------------------------------------------------
From: zhangchujun <zhangchujun@cmss.chinamobile.com>
Subject: selftests/cgroup: test_zswap: check malloc() return value
Date: Wed, 04 Nov 2026 17:53:15 +0800

test_no_invasive_cgroup_shrink() uses zw_allocation immediately after
malloc() without checking for allocation failure.

Check for NULL before accessing the buffer and use the existing cleanup
path to report test failure, matching the handling of wb_allocation later
in the function.

Link: https://lore.kernel.org/20261104095315.2326-1-zhangchujun@cmss.chinamobile.com
Signed-off-by: zhangchujun <zhangchujun@cmss.chinamobile.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Yosry Ahmed <yosry@kernel.org>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
---

 tools/testing/selftests/cgroup/test_zswap.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/tools/testing/selftests/cgroup/test_zswap.c~selftests-cgroup-test_zswap-check-malloc-return-value
+++ a/tools/testing/selftests/cgroup/test_zswap.c
@@ -503,6 +503,8 @@ static int test_no_invasive_cgroup_shrin
 	if (cg_enter_current(zw_group))
 		goto out;
 	zw_allocation = malloc(allocation_size);
+	if (!zw_allocation)
+		goto out;
 	for (int i = 0; i < nr_pages; i++) {
 		off = (unsigned long)i * page_size;
 		memset(&zw_allocation[off], 0, page_size);
_

Patches currently in -mm which might be from zhangchujun@cmss.chinamobile.com are

mm-page_owner-use-%u-to-print-the-stack-depot-handle.patch
selftests-cgroup-test_zswap-check-malloc-return-value.patch