From b9c28286d8f1822a10f702fcefe0b8a1db4e6917 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Sat, 24 Jul 2021 23:47:33 +0200 Subject: [PATCH] nfc: constify nci_ops 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 Signed-off-by: David S. Miller --- 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 5287458..73f5184 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 a4620b4..6e9e7ce 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 2b0c723..518e2af 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 110ff12..f6fce34 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 f73ee0b..b914ab2 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 bf573ec..5dae7e2 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 09967b8..a7d26f2 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; -- 2.7.4