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But if it is not, kdamond will terminate unexpectedly due to the user's invalid input. Solution ======== Add the same check to damon_{lru_sort, reclaim}_apply_parameters(), but return -EINVAL immediately. This is to prevent user's invalid input causing kdamond to terminate unexpectedly. This patch is a follow-up to the discussion in [1], where we agreed that the validation should be done on min_region_sz rather than addr_unit. [1] https://lore.kernel.org/20260330233343.4083-1-sj@kernel.org Signed-off-by: Liew Rui Yan --- Changes from v1: - Fix memory leak issue. - Link to v1: https://lore.kernel.org/20260331073231.30060-1-aethernet65535@gmail.com mm/damon/lru_sort.c | 5 +++++ mm/damon/reclaim.c | 5 +++++ 2 files changed, 10 insertions(+) diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c index 554559d72976..3fd176ef9d9c 100644 --- a/mm/damon/lru_sort.c +++ b/mm/damon/lru_sort.c @@ -294,6 +294,11 @@ static int damon_lru_sort_apply_parameters(void) param_ctx->addr_unit = addr_unit; param_ctx->min_region_sz = max(DAMON_MIN_REGION_SZ / addr_unit, 1); + if (!is_power_of_2(param_ctx->min_region_sz)) { + err = -EINVAL; + goto out; + } + if (!damon_lru_sort_mon_attrs.sample_interval) { err = -EINVAL; goto out; diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c index 86da14778658..2747eef5919d 100644 --- a/mm/damon/reclaim.c +++ b/mm/damon/reclaim.c @@ -204,6 +204,11 @@ static int damon_reclaim_apply_parameters(void) param_ctx->addr_unit = addr_unit; param_ctx->min_region_sz = max(DAMON_MIN_REGION_SZ / addr_unit, 1); + if (!is_power_of_2(param_ctx->min_region_sz)) { + err = -EINVAL; + goto out; + } + if (!damon_reclaim_mon_attrs.aggr_interval) { err = -EINVAL; goto out; -- 2.53.0