| Message ID | 20170612220223.GA6326@embeddedgus (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Samuel Ortiz |
| Headers | show |
On 06/12/2017 03:28 PM, Gustavo A. R. Silva wrote: > 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 ? > Exactly. >>> - 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 > > > > > > >
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) { - 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) { - 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; } }
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(-)