FAILED: patch "[PATCH] mm/damon/tests/core-kunit: handle memory alloc failure from" failed to apply to 5.15-stable tree

FAILED: patch "[PATCH] mm/damon/tests/core-kunit: handle memory alloc failure from" failed to apply to 5.15-stable tree

[gregkh]

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x f79f2fc44ebd0ed655239046be3e80e8804b5545
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026010546-gibberish-fracture-b6c1@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f79f2fc44ebd0ed655239046be3e80e8804b5545 Mon Sep 17 00:00:00 2001
From: SeongJae Park <sj@kernel.org>
Date: Sat, 1 Nov 2025 11:19:58 -0700
Subject: [PATCH] mm/damon/tests/core-kunit: handle memory alloc failure from
 damon_test_aggregate()

damon_test_aggregate() is assuming all dynamic memory allocation in it
will succeed.  Those are indeed likely in the real use cases since those
allocations are too small to fail, but theoretically those could fail.  In
the case, inappropriate memory access can happen.  Fix it by appropriately
cleanup pre-allocated memory and skip the execution of the remaining tests
in the failure cases.

Link: https://lkml.kernel.org/r/20251101182021.74868-5-sj@kernel.org
Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@google.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: <stable@vger.kernel.org>	[5.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h
index 6e8a605277a3..fd1e1ecaa2c9 100644
--- a/mm/damon/tests/core-kunit.h
+++ b/mm/damon/tests/core-kunit.h
@@ -97,8 +97,15 @@ static void damon_test_aggregate(struct kunit *test)
 	struct damon_region *r;
 	int it, ir;
 
+	if (!ctx)
+		kunit_skip(test, "ctx alloc fail");
+
 	for (it = 0; it < 3; it++) {
 		t = damon_new_target();
+		if (!t) {
+			damon_destroy_ctx(ctx);
+			kunit_skip(test, "target alloc fail");
+		}
 		damon_add_target(ctx, t);
 	}
 
@@ -106,6 +113,10 @@ static void damon_test_aggregate(struct kunit *test)
 	damon_for_each_target(t, ctx) {
 		for (ir = 0; ir < 3; ir++) {
 			r = damon_new_region(saddr[it][ir], eaddr[it][ir]);
+			if (!r) {
+				damon_destroy_ctx(ctx);
+				kunit_skip(test, "region alloc fail");
+			}
 			r->nr_accesses = accesses[it][ir];
 			r->nr_accesses_bp = accesses[it][ir] * 10000;
 			damon_add_region(r, t);

[PATCH 5.15.y] mm/damon/tests/core-kunit: handle memory alloc failure from damon_test_aggregate()

[SeongJae Park]

damon_test_aggregate() is assuming all dynamic memory allocation in it
will succeed.  Those are indeed likely in the real use cases since those
allocations are too small to fail, but theoretically those could fail.  In
the case, inappropriate memory access can happen.  Fix it by appropriately
cleanup pre-allocated memory and skip the execution of the remaining tests
in the failure cases.

Link: https://lkml.kernel.org/r/20251101182021.74868-5-sj@kernel.org
Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@google.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: <stable@vger.kernel.org>	[5.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit f79f2fc44ebd0ed655239046be3e80e8804b5545)
Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/core-test.h | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h
index 7008c3735e99..e60d47b344b0 100644
--- a/mm/damon/core-test.h
+++ b/mm/damon/core-test.h
@@ -86,12 +86,22 @@ static void damon_test_aggregate(struct kunit *test)
 	struct damon_region *r;
 	int it, ir;
 
-	damon_set_targets(ctx, target_ids, 3);
+	if (!ctx)
+		kunit_skip(test, "ctx alloc fail");
+
+	if (damon_set_targets(ctx, target_ids, 3)) {
+		damon_destroy_ctx(ctx);
+		kunit_skip(test, "target alloc fail");
+	}
 
 	it = 0;
 	damon_for_each_target(t, ctx) {
 		for (ir = 0; ir < 3; ir++) {
 			r = damon_new_region(saddr[it][ir], eaddr[it][ir]);
+			if (!r) {
+				damon_destroy_ctx(ctx);
+				kunit_skip(test, "region alloc fail");
+			}
 			r->nr_accesses = accesses[it][ir];
 			damon_add_region(r, t);
 		}
-- 
2.47.3