[PATCH 1/2] mm/damon/sysfs: catch commit test ctx alloc failure

[SeongJae Park <sj@kernel.org>]

The damon_ctx for testing online DAMON parameters commit inputs is used
without its allocation failure check.  This could result in an invalid
memory access.  Fix it by directly returning an error when the
allocation failed.

Fixes: 4c9ea539ad59 ("mm/damon/sysfs: validate user inputs from damon_sysfs_commit_input()")
Cc: <stable@vger.kernel.org> # 6.15.x
Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/sysfs.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index a212877ed240..27ebfe016871 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -1473,6 +1473,8 @@ static int damon_sysfs_commit_input(void *data)
 	if (IS_ERR(param_ctx))
 		return PTR_ERR(param_ctx);
 	test_ctx = damon_new_ctx();
+	if (!test_ctx)
+		return -ENOMEM;
 	err = damon_commit_ctx(test_ctx, param_ctx);
 	if (err) {
 		damon_destroy_ctx(test_ctx);
-- 
2.39.5