lkml.org 
[lkml]   [2017]   [Jun]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: nfc: nci: fix potential NULL pointer dereference
Hi Guenter,

Please, see my comments below

Quoting Guenter Roeck <linux@roeck-us.net>:

> On Mon, Jun 12, 2017 at 05:02:23PM -0500, Gustavo A. R. Silva wrote:
>> NULL check at line 76: if (conn_info) {, implies that pointer conn_info
>> might be NULL, but this pointer is being previously dereferenced,
>> which might cause a NULL pointer dereference.
>>
>> Add NULL check before dereferencing pointer conn_info in order to
>> avoid a potential NULL pointer dereference.
>>
>> Addresses-Coverity-ID: 1362349
>> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
>> ---
>> net/nfc/nci/core.c | 11 +++++------
>> 1 file changed, 5 insertions(+), 6 deletions(-)
>>
>> diff --git a/net/nfc/nci/core.c b/net/nfc/nci/core.c
>> index 61fff42..d2198ce 100644
>> --- a/net/nfc/nci/core.c
>> +++ b/net/nfc/nci/core.c
>> @@ -70,14 +70,13 @@ int
>> nci_get_conn_info_by_dest_type_params(struct nci_dev *ndev, u8
>> dest_type,
>> struct nci_conn_info *conn_info;
>>
>> list_for_each_entry(conn_info, &ndev->conn_info_list, list) {
>
> conn_info is set in list_for_each_entry() using container_of(),
> which is never NULL. Plus, it is dereferenced there as well.
> The check is unnecessary.
>

Thanks for clarifying.

> Guenter
>
>> - if (conn_info->dest_type == dest_type) {
>> + if (conn_info && conn_info->dest_type == dest_type) {
>> if (!params)
>> return conn_info->conn_id;
>> - if (conn_info) {

So, this NULL check could be removed as it seems it is not useful at all ?

>> - if (params->id == conn_info->dest_params->id &&
>> - params->protocol == conn_info->dest_params->protocol)
>> - return conn_info->conn_id;
>> - }
>> +
>> + if (params->id == conn_info->dest_params->id &&
>> + params->protocol == conn_info->dest_params->protocol)
>> + return conn_info->conn_id;
>> }
>> }
>>

Thank you
--
Gustavo A. R. Silva






\
 
 \ /
  Last update: 2017-06-13 00:53    [W:0.493 / U:0.000 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site