device property: avoid allocations of 0 length

Arrays can not have zero elements by definition of the unified device
properties. If such property comes from outside we should not allow it to pass.
Otherwise memory allocation on 0 length will return non-NULL value, which we
currently don't check.

Prevent memory allocations of 0 length.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/base/property.c b/drivers/base/property.c
index b3429cc4ee63da94ac69df5d83dc05bd5a5980b3..c359351d50f1c99e9758b74ea84d97e76b402b0f 100644 (file)
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -653,6 +653,9 @@ int fwnode_property_match_string(struct fwnode_handle *fwnode,
        if (nval < 0)
                return nval;
 
+       if (nval == 0)
+               return -ENODATA;
+
        values = kcalloc(nval, sizeof(*values), GFP_KERNEL);
        if (!values)
                return -ENOMEM;
@@ -718,6 +721,9 @@ static int pset_copy_entry(struct property_entry *dst,
                return -ENOMEM;
 
        if (src->is_array) {
+               if (!src->length)
+                       return -ENODATA;
+
                if (src->is_string) {
                        nval = src->length / sizeof(const char *);
                        dst->pointer.str = kcalloc(nval, sizeof(const char *),