Commit f688d619 authored by Stefano Stabellini's avatar Stefano Stabellini Committed by Rob Herring
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of: of_property_read_string return -ENODATA when !length 



When the length of the string is zero of_property_read_string should
return -ENODATA according to the description of the function.

However, of_property_read_string doesn't check prop->length. If
prop->length is zero, return -ENODATA.

Without this patch the following command in u-boot:

fdt set /chosen/node property-name

results in of_property_read_string returning -EILSEQ when attempting to
read property-name. With this patch, it returns -ENODATA as expected.

Signed-off-by: default avatarStefano Stabellini <stefano.stabellini@xilinx.com>
Signed-off-by: default avatarRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220416003028.1315268-1-sstabellini@kernel.org
parent f2701e0f

drivers/of/property.c

+4 −1
Original line number Diff line number Diff line
@@ -431,6 +431,9 @@ EXPORT_SYMBOL_GPL(of_property_read_variable_u64_array); 
 * property does not have a value, and -EILSEQ if the string is not

 * null-terminated within the length of the property data.

 *

 * Note that the empty string "" has length of 1, thus -ENODATA cannot

 * be interpreted as an empty string.

 *

 * The out_string pointer is modified only if a valid string can be decoded.

 */

int of_property_read_string(const struct device_node *np, const char *propname,
@@ -439,7 +442,7 @@ int of_property_read_string(const struct device_node *np, const char *propname, 
	const struct property *prop = of_find_property(np, propname, NULL);

	if (!prop)

		return -EINVAL;

	if (!prop->value)

	if (!prop->length)

		return -ENODATA;

	if (strnlen(prop->value, prop->length) >= prop->length)

		return -EILSEQ;