diff options
| author | Quanmin Yan <yanquanmin1@huawei.com> | 2025-08-27 19:58:57 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-09-19 16:35:46 +0200 |
| commit | af0ae62b935317bed1a1361c8c9579db9d300e70 (patch) | |
| tree | 257b36ec73ea7190ad2223430bdb670d87da5020 | |
| parent | 1797fd7b431c442b90b3a90b9f6bbf6915eb29e5 (diff) | |
mm/damon/lru_sort: avoid divide-by-zero in damon_lru_sort_apply_parameters()
commit 711f19dfd783ffb37ca4324388b9c4cb87e71363 upstream.
Patch series "mm/damon: avoid divide-by-zero in DAMON module's parameters
application".
DAMON's RECLAIM and LRU_SORT modules perform no validation on
user-configured parameters during application, which may lead to
division-by-zero errors.
Avoid the divide-by-zero by adding validation checks when DAMON modules
attempt to apply the parameters.
This patch (of 2):
During the calculation of 'hot_thres' and 'cold_thres', either
'sample_interval' or 'aggr_interval' is used as the divisor, which may
lead to division-by-zero errors. Fix it by directly returning -EINVAL
when such a case occurs. Additionally, since 'aggr_interval' is already
required to be set no smaller than 'sample_interval' in damon_set_attrs(),
only the case where 'sample_interval' is zero needs to be checked.
Link: https://lkml.kernel.org/r/20250827115858.1186261-2-yanquanmin1@huawei.com
Fixes: 40e983cca927 ("mm/damon: introduce DAMON-based LRU-lists Sorting")
Signed-off-by: Quanmin Yan <yanquanmin1@huawei.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: ze zuo <zuoze1@huawei.com>
Cc: <stable@vger.kernel.org> [6.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | mm/damon/lru_sort.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c index 4af8fd4a390b..c2b4f0b07147 100644 --- a/mm/damon/lru_sort.c +++ b/mm/damon/lru_sort.c @@ -198,6 +198,11 @@ static int damon_lru_sort_apply_parameters(void) if (err) return err; + if (!damon_lru_sort_mon_attrs.sample_interval) { + err = -EINVAL; + goto out; + } + err = damon_set_attrs(ctx, &damon_lru_sort_mon_attrs); if (err) goto out; |