Right now we don't check for valid module parameter value for block size, that allows user to set negative values. Add a callback to error out when block size value is set < 1 before module is loaded. Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx> --- drivers/block/null_blk/main.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c index 51aa202159cb..8f7c6f8c2132 100644 --- a/drivers/block/null_blk/main.c +++ b/drivers/block/null_blk/main.c @@ -179,8 +179,18 @@ static int g_gb = 250; device_param_cb(gb, &null_gb_param_ops, &g_gb, 0444); MODULE_PARM_DESC(gb, "Size in GB"); +static int null_set_bs(const char *s, const struct kernel_param *kp) +{ + return null_param_store_int(s, kp->arg, 512, INT_MAX); +} + +static const struct kernel_param_ops null_bs_param_ops = { + .set = null_set_bs, + .get = param_get_int, +}; + static int g_bs = 512; -module_param_named(bs, g_bs, int, 0444); +device_param_cb(bs, &null_bs_param_ops, &g_bs, 0444); MODULE_PARM_DESC(bs, "Block size (in bytes)"); static int g_max_sectors; -- 2.29.0