From: Stefano Stabellini <stefano.stabellini@xxxxxxxxxx> 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: Stefano Stabellini <stefano.stabellini@xxxxxxxxxx> --- Changes in v2: - use prop instead pp - drop value check - update function header documentation --- drivers/of/property.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/of/property.c b/drivers/of/property.c index 8e90071de6ed..84903dad96a4 100644 --- a/drivers/of/property.c +++ b/drivers/of/property.c @@ -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; -- 2.25.1
