6.18-stable review patch. If anyone has any objections, please let me know.
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From: SeongJae Park sj@kernel.org
damon_test_split_regions_of() 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/20251101182021.74868-9-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 eded254cb69044bd4abde87394ea44909708d7c0) Signed-off-by: SeongJae Park sj@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- mm/damon/tests/core-kunit.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)
--- a/mm/damon/tests/core-kunit.h +++ b/mm/damon/tests/core-kunit.h @@ -278,15 +278,35 @@ static void damon_test_split_regions_of( struct damon_target *t; struct damon_region *r;
+ if (!c) + kunit_skip(test, "ctx alloc fail"); t = damon_new_target(); + if (!t) { + damon_destroy_ctx(c); + kunit_skip(test, "target alloc fail"); + } r = damon_new_region(0, 22); + if (!r) { + damon_destroy_ctx(c); + damon_free_target(t); + kunit_skip(test, "region alloc fail"); + } damon_add_region(r, t); damon_split_regions_of(t, 2, DAMON_MIN_REGION); KUNIT_EXPECT_LE(test, damon_nr_regions(t), 2u); damon_free_target(t);
t = damon_new_target(); + if (!t) { + damon_destroy_ctx(c); + kunit_skip(test, "second target alloc fail"); + } r = damon_new_region(0, 220); + if (!r) { + damon_destroy_ctx(c); + damon_free_target(t); + kunit_skip(test, "second region alloc fail"); + } damon_add_region(r, t); damon_split_regions_of(t, 4, DAMON_MIN_REGION); KUNIT_EXPECT_LE(test, damon_nr_regions(t), 4u);