The callback return value is ignored in damon_sysfs_damon_call(), which means that it is not possible to detect invalid user input when writing commands such as 'commit' to /sys/kernel/mm/damon/admin/kdamonds/<K>/state. Fix it.

Signed-off-by: Akinobu Mita akinobu.mita@gmail.com Fixes: f64539dcdb87 ("mm/damon/sysfs: use damon_call() for update_schemes_stats") Cc: stable@vger.kernel.org # v6.14.x Reviewed-by: SeongJae Park sj@kernel.org --- mm/damon/sysfs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index fe4e73d0ebbb..3ffe3a77b5db 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -1627,12 +1627,14 @@ static int damon_sysfs_damon_call(int (*fn)(void *data), struct damon_sysfs_kdamond *kdamond) { struct damon_call_control call_control = {}; + int err;

if (!kdamond->damon_ctx) return -EINVAL; call_control.fn = fn; call_control.data = kdamond; - return damon_call(kdamond->damon_ctx, &call_control); + err = damon_call(kdamond->damon_ctx, &call_control); + return err ? err : call_control.return_code; }

struct damon_sysfs_schemes_walk_data {