| Message ID | 20190208004033.GA15609@embeddedor |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | David Miller |
| Headers | show |
| Series | [next] Bluetooth: hci_event: Use struct_size() helper | expand |
On Thu, 2019-02-07 at 18:40 -0600, Gustavo A. R. Silva wrote: > Make use of the struct_size() helper instead of an open-coded version > in order to avoid any potential type mistakes, in particular in the > context in which this code is being used. > > So, change the following form: > > sizeof(*ev) + ev->num_hndl * sizeof(struct hci_comp_pkts_info) > > to : > > struct_size(ev, handles, ev->num_hndl) > > This code was detected with the help of Coccinelle. [] > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c [] > @@ -3556,8 +3556,8 @@ static void hci_num_comp_pkts_evt(struct hci_dev *hdev, struct sk_buff *skb) > return; > } > > - if (skb->len < sizeof(*ev) || skb->len < sizeof(*ev) + > - ev->num_hndl * sizeof(struct hci_comp_pkts_info)) { > + if (skb->len < sizeof(*ev) || > + skb->len < struct_size(ev, handles, ev->num_hndl)) { > BT_DBG("%s bad parameters", hdev->name); > return; > } > @@ -3644,8 +3644,8 @@ static void hci_num_comp_blocks_evt(struct hci_dev *hdev, struct sk_buff *skb) > return; > } > > - if (skb->len < sizeof(*ev) || skb->len < sizeof(*ev) + > - ev->num_hndl * sizeof(struct hci_comp_blocks_info)) { > + if (skb->len < sizeof(*ev) || > + skb->len < struct_size(ev, handles, ev->num_hndl)) { Unless these are in a real fast path where skb->len < sizeof(*ev) is pretty likely, it seems a bit redundant as the multiplication is pretty cheap and num_hndl is unsigned (actually __u8) This could/should be simply if (skb->len < struct_size(...))
Hi Gustavo, > Make use of the struct_size() helper instead of an open-coded version > in order to avoid any potential type mistakes, in particular in the > context in which this code is being used. > > So, change the following form: > > sizeof(*ev) + ev->num_hndl * sizeof(struct hci_comp_pkts_info) > > to : > > struct_size(ev, handles, ev->num_hndl) > > This code was detected with the help of Coccinelle. > > Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> > --- > net/bluetooth/hci_event.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) patch has been applied to bluetooth-next tree. Regards Marcel
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index ac2826ce162b..609fd6871c5a 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -3556,8 +3556,8 @@ static void hci_num_comp_pkts_evt(struct hci_dev *hdev, struct sk_buff *skb) return; } - if (skb->len < sizeof(*ev) || skb->len < sizeof(*ev) + - ev->num_hndl * sizeof(struct hci_comp_pkts_info)) { + if (skb->len < sizeof(*ev) || + skb->len < struct_size(ev, handles, ev->num_hndl)) { BT_DBG("%s bad parameters", hdev->name); return; } @@ -3644,8 +3644,8 @@ static void hci_num_comp_blocks_evt(struct hci_dev *hdev, struct sk_buff *skb) return; } - if (skb->len < sizeof(*ev) || skb->len < sizeof(*ev) + - ev->num_hndl * sizeof(struct hci_comp_blocks_info)) { + if (skb->len < sizeof(*ev) || + skb->len < struct_size(ev, handles, ev->num_hndl)) { BT_DBG("%s bad parameters", hdev->name); return; }
Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes, in particular in the context in which this code is being used. So, change the following form: sizeof(*ev) + ev->num_hndl * sizeof(struct hci_comp_pkts_info) to : struct_size(ev, handles, ev->num_hndl) This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> --- net/bluetooth/hci_event.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)