Right now we don't check for valid module parameter value for
max_sectors, that allows user to set negative values.
Add a callback to error out when max_sectors value is set < 1 before
module is loaded.
Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx>
---
drivers/block/null_blk/main.c | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index d8d79c66a7aa..c13f0f2b8d86 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -209,8 +209,23 @@ static int g_bs = 512;
device_param_cb(bs, &null_bs_param_ops, &g_bs, 0444);
MODULE_PARM_DESC(bs, "Block size (in bytes)");
+static int null_set_max_sects(const char *s, const struct kernel_param *kp)
+{
+ int ret;
+
+ ret = null_param_store_int(s, kp->arg, 1, INT_MAX);
+ if (ret)
+ pr_err("only positive values are allowed for max_sectors\n");
+ return ret;
+}
+
+static const struct kernel_param_ops null_max_sects_param_ops = {
+ .set = null_set_max_sects,
+ .get = param_get_int,
+};
+
static int g_max_sectors;
-module_param_named(max_sectors, g_max_sectors, int, 0444);
+device_param_cb(max_sectors, &null_max_sects_param_ops, &g_max_sectors, 0444);
MODULE_PARM_DESC(max_sectors, "Maximum size of a command (in 512B sectors)");
static unsigned int nr_devices = 1;
--
2.29.0
