From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756890AbcIFPCK (ORCPT ); Tue, 6 Sep 2016 11:02:10 -0400 Received: from mx0a-001ae601.pphosted.com ([67.231.149.25]:47533 "EHLO mx0b-001ae601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756521AbcIFPCH (ORCPT ); Tue, 6 Sep 2016 11:02:07 -0400 Authentication-Results: ppops.net; spf=none smtp.mailfrom=rf@opensource.wolfsonmicro.com From: Richard Fitzgerald To: , CC: , , Subject: [PATCH 1/2] of: Make of_find_property_value_of_size take a length range Date: Tue, 6 Sep 2016 16:02:00 +0100 Message-ID: <1473174121-19742-1-git-send-email-rf@opensource.wolfsonmicro.com> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 impostorscore=0 lowpriorityscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1604210000 definitions=main-1609060232 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In preparation for adding variable-length array reads, change of_find_property_value_of_size so that it takes an optional maximum length. If the maximum is passed as 0, the behaviour is unchanged and it will return a property if it's >= the requested minimum length. If maximum is non-zero it will only return a property whose length is min <= l <= max. Signed-off-by: Richard Fitzgerald --- drivers/of/base.c | 39 +++++++++++++++++++++++++++++---------- 1 file changed, 29 insertions(+), 10 deletions(-) diff --git a/drivers/of/base.c b/drivers/of/base.c index 3ce6953..b853737 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -1146,16 +1146,18 @@ EXPORT_SYMBOL_GPL(of_property_count_elems_of_size); * * @np: device node from which the property value is to be read. * @propname: name of the property to be searched. - * @len: requested length of property value + * @min: minimum allowed length of property value + * @max: maximum allowed length of property value (0 means unlimited) + * @len: if !=NULL, actual length is written to here * * Search for a property in a device node and valid the requested size. * Returns the property value on success, -EINVAL if the property does not * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the - * property data isn't large enough. + * property data is too small or too large. * */ static void *of_find_property_value_of_size(const struct device_node *np, - const char *propname, u32 len) + const char *propname, u32 min, u32 max, size_t *len) { struct property *prop = of_find_property(np, propname, NULL); @@ -1163,8 +1165,13 @@ static void *of_find_property_value_of_size(const struct device_node *np, return ERR_PTR(-EINVAL); if (!prop->value) return ERR_PTR(-ENODATA); - if (len > prop->length) + if (prop->length < min) return ERR_PTR(-EOVERFLOW); + if (max && prop->length > max) + return ERR_PTR(-EOVERFLOW); + + if (len) + *len = prop->length; return prop->value; } @@ -1189,7 +1196,9 @@ int of_property_read_u32_index(const struct device_node *np, u32 index, u32 *out_value) { const u32 *val = of_find_property_value_of_size(np, propname, - ((index + 1) * sizeof(*out_value))); + ((index + 1) * sizeof(*out_value)), + 0, + NULL); if (IS_ERR(val)) return PTR_ERR(val); @@ -1221,7 +1230,9 @@ int of_property_read_u8_array(const struct device_node *np, const char *propname, u8 *out_values, size_t sz) { const u8 *val = of_find_property_value_of_size(np, propname, - (sz * sizeof(*out_values))); + (sz * sizeof(*out_values)), + 0, + NULL); if (IS_ERR(val)) return PTR_ERR(val); @@ -1254,7 +1265,9 @@ int of_property_read_u16_array(const struct device_node *np, const char *propname, u16 *out_values, size_t sz) { const __be16 *val = of_find_property_value_of_size(np, propname, - (sz * sizeof(*out_values))); + (sz * sizeof(*out_values)), + 0, + NULL); if (IS_ERR(val)) return PTR_ERR(val); @@ -1286,7 +1299,9 @@ int of_property_read_u32_array(const struct device_node *np, size_t sz) { const __be32 *val = of_find_property_value_of_size(np, propname, - (sz * sizeof(*out_values))); + (sz * sizeof(*out_values)), + 0, + NULL); if (IS_ERR(val)) return PTR_ERR(val); @@ -1314,7 +1329,9 @@ int of_property_read_u64(const struct device_node *np, const char *propname, u64 *out_value) { const __be32 *val = of_find_property_value_of_size(np, propname, - sizeof(*out_value)); + sizeof(*out_value), + 0, + NULL); if (IS_ERR(val)) return PTR_ERR(val); @@ -1345,7 +1362,9 @@ int of_property_read_u64_array(const struct device_node *np, size_t sz) { const __be32 *val = of_find_property_value_of_size(np, propname, - (sz * sizeof(*out_values))); + (sz * sizeof(*out_values)), + 0, + NULL); if (IS_ERR(val)) return PTR_ERR(val); -- 1.9.1