The struct nci_ops is modified by NFC core in only one case:
nci_allocate_device() receives too many proprietary commands (prop_ops)
to configure. This is a build time known constrain, so a graceful
handling of such case is not necessary.
Instead, fail the nci_allocate_device() and add BUILD_BUG_ON() to places
which set these.
This allows to constify the struct nci_ops (consisting of function
pointers) for correctness and safety.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
---
drivers/nfc/fdp/fdp.c | 3 ++-
drivers/nfc/nfcmrvl/main.c | 2 +-
drivers/nfc/nxp-nci/core.c | 2 +-
drivers/nfc/st-nci/core.c | 3 ++-
drivers/nfc/virtual_ncidev.c | 2 +-
include/net/nfc/nci_core.h | 4 ++--
net/nfc/nci/core.c | 5 ++---
7 files changed, 11 insertions(+), 10 deletions(-)
diff --git a/drivers/nfc/fdp/fdp.c b/drivers/nfc/fdp/fdp.c
index 528745862738..73f51848a693 100644
--- a/drivers/nfc/fdp/fdp.c
+++ b/drivers/nfc/fdp/fdp.c
@@ -675,7 +675,7 @@ static struct nci_driver_ops fdp_prop_ops[] = {
},
};
-static struct nci_ops nci_ops = {
+static const struct nci_ops nci_ops = {
.open = fdp_nci_open,
.close = fdp_nci_close,
.send = fdp_nci_send,
@@ -718,6 +718,7 @@ int fdp_nci_probe(struct fdp_i2c_phy *phy, struct nfc_phy_ops *phy_ops,
NFC_PROTO_NFC_DEP_MASK |
NFC_PROTO_ISO15693_MASK;
+ BUILD_BUG_ON(ARRAY_SIZE(fdp_prop_ops) > NCI_MAX_PROPRIETARY_CMD);
ndev = nci_allocate_device(&nci_ops, protocols, tx_headroom,
tx_tailroom);
if (!ndev) {
diff --git a/drivers/nfc/nfcmrvl/main.c b/drivers/nfc/nfcmrvl/main.c
index a4620b480c4f..6e9e7ce8792c 100644
--- a/drivers/nfc/nfcmrvl/main.c
+++ b/drivers/nfc/nfcmrvl/main.c
@@ -81,7 +81,7 @@ static int nfcmrvl_nci_fw_download(struct nci_dev *ndev,
return nfcmrvl_fw_dnld_start(ndev, firmware_name);
}
-static struct nci_ops nfcmrvl_nci_ops = {
+static const struct nci_ops nfcmrvl_nci_ops = {
.open = nfcmrvl_nci_open,
.close = nfcmrvl_nci_close,
.send = nfcmrvl_nci_send,
diff --git a/drivers/nfc/nxp-nci/core.c b/drivers/nfc/nxp-nci/core.c
index 2b0c7232e91f..518e2afb43a8 100644
--- a/drivers/nfc/nxp-nci/core.c
+++ b/drivers/nfc/nxp-nci/core.c
@@ -83,7 +83,7 @@ static int nxp_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
return r;
}
-static struct nci_ops nxp_nci_ops = {
+static const struct nci_ops nxp_nci_ops = {
.open = nxp_nci_open,
.close = nxp_nci_close,
.send = nxp_nci_send,
diff --git a/drivers/nfc/st-nci/core.c b/drivers/nfc/st-nci/core.c
index 110ff1281e5f..f6fce34a77da 100644
--- a/drivers/nfc/st-nci/core.c
+++ b/drivers/nfc/st-nci/core.c
@@ -94,7 +94,7 @@ static struct nci_driver_ops st_nci_prop_ops[] = {
},
};
-static struct nci_ops st_nci_ops = {
+static const struct nci_ops st_nci_ops = {
.init = st_nci_init,
.open = st_nci_open,
.close = st_nci_close,
@@ -131,6 +131,7 @@ int st_nci_probe(struct llt_ndlc *ndlc, int phy_headroom,
| NFC_PROTO_ISO15693_MASK
| NFC_PROTO_NFC_DEP_MASK;
+ BUILD_BUG_ON(ARRAY_SIZE(st_nci_prop_ops) > NCI_MAX_PROPRIETARY_CMD);
ndlc->ndev = nci_allocate_device(&st_nci_ops, protocols,
phy_headroom, phy_tailroom);
if (!ndlc->ndev) {
diff --git a/drivers/nfc/virtual_ncidev.c b/drivers/nfc/virtual_ncidev.c
index f73ee0bf3593..b914ab2c2109 100644
--- a/drivers/nfc/virtual_ncidev.c
+++ b/drivers/nfc/virtual_ncidev.c
@@ -65,7 +65,7 @@ static int virtual_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
return 0;
}
-static struct nci_ops virtual_nci_ops = {
+static const struct nci_ops virtual_nci_ops = {
.open = virtual_nci_open,
.close = virtual_nci_close,
.send = virtual_nci_send
diff --git a/include/net/nfc/nci_core.h b/include/net/nfc/nci_core.h
index bf573eca07ca..5dae7e2cbc49 100644
--- a/include/net/nfc/nci_core.h
+++ b/include/net/nfc/nci_core.h
@@ -194,7 +194,7 @@ struct nci_hci_dev {
/* NCI Core structures */
struct nci_dev {
struct nfc_dev *nfc_dev;
- struct nci_ops *ops;
+ const struct nci_ops *ops;
struct nci_hci_dev *hci_dev;
int tx_headroom;
@@ -267,7 +267,7 @@ struct nci_dev {
};
/* ----- NCI Devices ----- */
-struct nci_dev *nci_allocate_device(struct nci_ops *ops,
+struct nci_dev *nci_allocate_device(const struct nci_ops *ops,
__u32 supported_protocols,
int tx_headroom,
int tx_tailroom);
diff --git a/net/nfc/nci/core.c b/net/nfc/nci/core.c
index 09967b836361..a7d26f2791b0 100644
--- a/net/nfc/nci/core.c
+++ b/net/nfc/nci/core.c
@@ -1129,7 +1129,7 @@ static struct nfc_ops nci_nfc_ops = {
* @tx_headroom: Reserved space at beginning of skb
* @tx_tailroom: Reserved space at end of skb
*/
-struct nci_dev *nci_allocate_device(struct nci_ops *ops,
+struct nci_dev *nci_allocate_device(const struct nci_ops *ops,
__u32 supported_protocols,
int tx_headroom, int tx_tailroom)
{
@@ -1152,8 +1152,7 @@ struct nci_dev *nci_allocate_device(struct nci_ops *ops,
if (ops->n_prop_ops > NCI_MAX_PROPRIETARY_CMD) {
pr_err("Too many proprietary commands: %zd\n",
ops->n_prop_ops);
- ops->prop_ops = NULL;
- ops->n_prop_ops = 0;
+ goto free_nci;
}
ndev->tx_headroom = tx_headroom;
--
2.27.0
