Commit 8d532528 authored by Russell King (Oracle)'s avatar Russell King (Oracle)
Browse files

clkdev: report over-sized strings when creating clkdev entries 



Report an error when an attempt to register a clkdev entry results in a
truncated string so the problem can be easily spotted.

Reported by: Duanqiang Wen <duanqiangwen@net-swift.com>
Signed-off-by: default avatarRussell King (Oracle) <rmk+kernel@armlinux.org.uk>
parent e8f897f4

drivers/clk/clkdev.c

+33 −2
Original line number Diff line number Diff line
@@ -158,23 +158,54 @@ vclkdev_alloc(struct clk_hw *hw, const char *con_id, const char *dev_fmt, 
	va_list ap)

{

	struct clk_lookup_alloc *cla;

	struct va_format vaf;

	const char *failure;

	va_list ap_copy;

	size_t max_size;

	ssize_t res;



	cla = kzalloc(sizeof(*cla), GFP_KERNEL);

	if (!cla)

		return NULL;



	va_copy(ap_copy, ap);



	cla->cl.clk_hw = hw;

	if (con_id) {

		strscpy(cla->con_id, con_id, sizeof(cla->con_id));

		res = strscpy(cla->con_id, con_id, sizeof(cla->con_id));

		if (res < 0) {

			max_size = sizeof(cla->con_id);

			failure = "connection";

			goto fail;

		}

		cla->cl.con_id = cla->con_id;

	}



	if (dev_fmt) {

		vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap);

		res = vsnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap);

		if (res >= sizeof(cla->dev_id)) {

			max_size = sizeof(cla->dev_id);

			failure = "device";

			goto fail;

		}

		cla->cl.dev_id = cla->dev_id;

	}



	va_end(ap_copy);



	return &cla->cl;



fail:

	if (dev_fmt)

		vaf.fmt = dev_fmt;

	else

		vaf.fmt = "null-device";

	vaf.va = &ap_copy;

	pr_err("%pV:%s: %s ID is greater than %zu\n",

	       &vaf, con_id, failure, max_size);

	va_end(ap_copy);

	kfree(cla);

	return NULL;

}



static struct clk_lookup *