nfc: constify several pointers to u8, char and sk_buff

Several functions receive pointers to u8, char or sk_buff but do not
modify the contents so make them const.  This allows doing the same for
local variables and in total makes the code a little bit safer.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/net/nfc/nfc.h b/include/net/nfc/nfc.h
index 9017791..5dee575 100644 (file)
--- a/include/net/nfc/nfc.h
+++ b/include/net/nfc/nfc.h
@@ -266,7 +266,7 @@ struct sk_buff *nfc_alloc_send_skb(struct nfc_dev *dev, struct sock *sk,
 struct sk_buff *nfc_alloc_recv_skb(unsigned int size, gfp_t gfp);
 
 int nfc_set_remote_general_bytes(struct nfc_dev *dev,
-                                u8 *gt, u8 gt_len);
+                                const u8 *gt, u8 gt_len);
 u8 *nfc_get_local_general_bytes(struct nfc_dev *dev, size_t *gb_len);
 
 int nfc_fw_download_done(struct nfc_dev *dev, const char *firmware_name,
@@ -280,7 +280,7 @@ int nfc_dep_link_is_up(struct nfc_dev *dev, u32 target_idx,
                       u8 comm_mode, u8 rf_mode);
 
 int nfc_tm_activated(struct nfc_dev *dev, u32 protocol, u8 comm_mode,
-                    u8 *gb, size_t gb_len);
+                    const u8 *gb, size_t gb_len);
 int nfc_tm_deactivated(struct nfc_dev *dev);
 int nfc_tm_data_received(struct nfc_dev *dev, struct sk_buff *skb);
 

diff --git a/net/nfc/core.c b/net/nfc/core.c
index 6ade541..08182e2 100644 (file)
--- a/net/nfc/core.c
+++ b/net/nfc/core.c
@@ -636,7 +636,7 @@ error:
        return rc;
 }
 
-int nfc_set_remote_general_bytes(struct nfc_dev *dev, u8 *gb, u8 gb_len)
+int nfc_set_remote_general_bytes(struct nfc_dev *dev, const u8 *gb, u8 gb_len)
 {
        pr_debug("dev_name=%s gb_len=%d\n", dev_name(&dev->dev), gb_len);
 
@@ -665,7 +665,7 @@ int nfc_tm_data_received(struct nfc_dev *dev, struct sk_buff *skb)
 EXPORT_SYMBOL(nfc_tm_data_received);
 
 int nfc_tm_activated(struct nfc_dev *dev, u32 protocol, u8 comm_mode,
-                    u8 *gb, size_t gb_len)
+                    const u8 *gb, size_t gb_len)
 {
        int rc;
 

diff --git a/net/nfc/hci/llc_shdlc.c b/net/nfc/hci/llc_shdlc.c
index 6b74785..aef750d 100644 (file)
--- a/net/nfc/hci/llc_shdlc.c
+++ b/net/nfc/hci/llc_shdlc.c
@@ -123,7 +123,7 @@ static bool llc_shdlc_x_lteq_y_lt_z(int x, int y, int z)
                return ((y >= x) || (y < z)) ? true : false;
 }
 
-static struct sk_buff *llc_shdlc_alloc_skb(struct llc_shdlc *shdlc,
+static struct sk_buff *llc_shdlc_alloc_skb(const struct llc_shdlc *shdlc,
                                           int payload_len)
 {
        struct sk_buff *skb;
@@ -137,7 +137,7 @@ static struct sk_buff *llc_shdlc_alloc_skb(struct llc_shdlc *shdlc,
 }
 
 /* immediately sends an S frame. */
-static int llc_shdlc_send_s_frame(struct llc_shdlc *shdlc,
+static int llc_shdlc_send_s_frame(const struct llc_shdlc *shdlc,
                                  enum sframe_type sframe_type, int nr)
 {
        int r;
@@ -159,7 +159,7 @@ static int llc_shdlc_send_s_frame(struct llc_shdlc *shdlc,
 }
 
 /* immediately sends an U frame. skb may contain optional payload */
-static int llc_shdlc_send_u_frame(struct llc_shdlc *shdlc,
+static int llc_shdlc_send_u_frame(const struct llc_shdlc *shdlc,
                                  struct sk_buff *skb,
                                  enum uframe_modifier uframe_modifier)
 {
@@ -361,7 +361,7 @@ static void llc_shdlc_connect_complete(struct llc_shdlc *shdlc, int r)
        wake_up(shdlc->connect_wq);
 }
 
-static int llc_shdlc_connect_initiate(struct llc_shdlc *shdlc)
+static int llc_shdlc_connect_initiate(const struct llc_shdlc *shdlc)
 {
        struct sk_buff *skb;
 
@@ -377,7 +377,7 @@ static int llc_shdlc_connect_initiate(struct llc_shdlc *shdlc)
        return llc_shdlc_send_u_frame(shdlc, skb, U_FRAME_RSET);
 }
 
-static int llc_shdlc_connect_send_ua(struct llc_shdlc *shdlc)
+static int llc_shdlc_connect_send_ua(const struct llc_shdlc *shdlc)
 {
        struct sk_buff *skb;
 

diff --git a/net/nfc/llcp.h b/net/nfc/llcp.h
index 97853c9..d49d4bf 100644 (file)
--- a/net/nfc/llcp.h
+++ b/net/nfc/llcp.h
@@ -221,15 +221,15 @@ struct sock *nfc_llcp_accept_dequeue(struct sock *sk, struct socket *newsock);
 
 /* TLV API */
 int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
-                         u8 *tlv_array, u16 tlv_array_len);
+                         const u8 *tlv_array, u16 tlv_array_len);
 int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
-                                 u8 *tlv_array, u16 tlv_array_len);
+                                 const u8 *tlv_array, u16 tlv_array_len);
 
 /* Commands API */
 void nfc_llcp_recv(void *data, struct sk_buff *skb, int err);
-u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length);
+u8 *nfc_llcp_build_tlv(u8 type, const u8 *value, u8 value_length, u8 *tlv_length);
 struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdres_tlv(u8 tid, u8 sap);
-struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdreq_tlv(u8 tid, char *uri,
+struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdreq_tlv(u8 tid, const char *uri,
                                                  size_t uri_len);
 void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp);
 void nfc_llcp_free_sdp_tlv_list(struct hlist_head *sdp_head);

diff --git a/net/nfc/llcp_commands.c b/net/nfc/llcp_commands.c
index 475061c..3c4172a 100644 (file)
--- a/net/nfc/llcp_commands.c
+++ b/net/nfc/llcp_commands.c
@@ -15,7 +15,7 @@
 #include "nfc.h"
 #include "llcp.h"
 
-static u8 llcp_tlv_length[LLCP_TLV_MAX] = {
+static const u8 llcp_tlv_length[LLCP_TLV_MAX] = {
        0,
        1, /* VERSION */
        2, /* MIUX */
@@ -29,7 +29,7 @@ static u8 llcp_tlv_length[LLCP_TLV_MAX] = {
 
 };
 
-static u8 llcp_tlv8(u8 *tlv, u8 type)
+static u8 llcp_tlv8(const u8 *tlv, u8 type)
 {
        if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
                return 0;
@@ -37,7 +37,7 @@ static u8 llcp_tlv8(u8 *tlv, u8 type)
        return tlv[2];
 }
 
-static u16 llcp_tlv16(u8 *tlv, u8 type)
+static u16 llcp_tlv16(const u8 *tlv, u8 type)
 {
        if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
                return 0;
@@ -46,37 +46,37 @@ static u16 llcp_tlv16(u8 *tlv, u8 type)
 }
 
 
-static u8 llcp_tlv_version(u8 *tlv)
+static u8 llcp_tlv_version(const u8 *tlv)
 {
        return llcp_tlv8(tlv, LLCP_TLV_VERSION);
 }
 
-static u16 llcp_tlv_miux(u8 *tlv)
+static u16 llcp_tlv_miux(const u8 *tlv)
 {
        return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
 }
 
-static u16 llcp_tlv_wks(u8 *tlv)
+static u16 llcp_tlv_wks(const u8 *tlv)
 {
        return llcp_tlv16(tlv, LLCP_TLV_WKS);
 }
 
-static u16 llcp_tlv_lto(u8 *tlv)
+static u16 llcp_tlv_lto(const u8 *tlv)
 {
        return llcp_tlv8(tlv, LLCP_TLV_LTO);
 }
 
-static u8 llcp_tlv_opt(u8 *tlv)
+static u8 llcp_tlv_opt(const u8 *tlv)
 {
        return llcp_tlv8(tlv, LLCP_TLV_OPT);
 }
 
-static u8 llcp_tlv_rw(u8 *tlv)
+static u8 llcp_tlv_rw(const u8 *tlv)
 {
        return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
 }
 
-u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length)
+u8 *nfc_llcp_build_tlv(u8 type, const u8 *value, u8 value_length, u8 *tlv_length)
 {
        u8 *tlv, length;
 
@@ -130,7 +130,7 @@ struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdres_tlv(u8 tid, u8 sap)
        return sdres;
 }
 
-struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdreq_tlv(u8 tid, char *uri,
+struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdreq_tlv(u8 tid, const char *uri,
                                                  size_t uri_len)
 {
        struct nfc_llcp_sdp_tlv *sdreq;
@@ -190,9 +190,10 @@ void nfc_llcp_free_sdp_tlv_list(struct hlist_head *head)
 }
 
 int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
-                         u8 *tlv_array, u16 tlv_array_len)
+                         const u8 *tlv_array, u16 tlv_array_len)
 {
-       u8 *tlv = tlv_array, type, length, offset = 0;
+       const u8 *tlv = tlv_array;
+       u8 type, length, offset = 0;
 
        pr_debug("TLV array length %d\n", tlv_array_len);
 
@@ -239,9 +240,10 @@ int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
 }
 
 int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
-                                 u8 *tlv_array, u16 tlv_array_len)
+                                 const u8 *tlv_array, u16 tlv_array_len)
 {
-       u8 *tlv = tlv_array, type, length, offset = 0;
+       const u8 *tlv = tlv_array;
+       u8 type, length, offset = 0;
 
        pr_debug("TLV array length %d\n", tlv_array_len);
 
@@ -295,7 +297,7 @@ static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
        return pdu;
 }
 
-static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv,
+static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, const u8 *tlv,
                                    u8 tlv_length)
 {
        /* XXX Add an skb length check */
@@ -389,9 +391,10 @@ int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
 {
        struct nfc_llcp_local *local;
        struct sk_buff *skb;
-       u8 *service_name_tlv = NULL, service_name_tlv_length;
-       u8 *miux_tlv = NULL, miux_tlv_length;
-       u8 *rw_tlv = NULL, rw_tlv_length, rw;
+       const u8 *service_name_tlv = NULL;
+       const u8 *miux_tlv = NULL;
+       const u8 *rw_tlv = NULL;
+       u8 service_name_tlv_length, miux_tlv_length,  rw_tlv_length, rw;
        int err;
        u16 size = 0;
        __be16 miux;
@@ -465,8 +468,9 @@ int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
 {
        struct nfc_llcp_local *local;
        struct sk_buff *skb;
-       u8 *miux_tlv = NULL, miux_tlv_length;
-       u8 *rw_tlv = NULL, rw_tlv_length, rw;
+       const u8 *miux_tlv = NULL;
+       const u8 *rw_tlv = NULL;
+       u8 miux_tlv_length, rw_tlv_length, rw;
        int err;
        u16 size = 0;
        __be16 miux;

diff --git a/net/nfc/llcp_core.c b/net/nfc/llcp_core.c
index cc99751..eaeb2b1 100644 (file)
--- a/net/nfc/llcp_core.c
+++ b/net/nfc/llcp_core.c
@@ -301,7 +301,7 @@ static char *wks[] = {
        "urn:nfc:sn:snep",
 };
 
-static int nfc_llcp_wks_sap(char *service_name, size_t service_name_len)
+static int nfc_llcp_wks_sap(const char *service_name, size_t service_name_len)
 {
        int sap, num_wks;
 
@@ -325,7 +325,7 @@ static int nfc_llcp_wks_sap(char *service_name, size_t service_name_len)
 
 static
 struct nfc_llcp_sock *nfc_llcp_sock_from_sn(struct nfc_llcp_local *local,
-                                           u8 *sn, size_t sn_len)
+                                           const u8 *sn, size_t sn_len)
 {
        struct sock *sk;
        struct nfc_llcp_sock *llcp_sock, *tmp_sock;
@@ -522,7 +522,7 @@ static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
 {
        u8 *gb_cur, version, version_length;
        u8 lto_length, wks_length, miux_length;
-       u8 *version_tlv = NULL, *lto_tlv = NULL,
+       const u8 *version_tlv = NULL, *lto_tlv = NULL,
           *wks_tlv = NULL, *miux_tlv = NULL;
        __be16 wks = cpu_to_be16(local->local_wks);
        u8 gb_len = 0;
@@ -612,7 +612,7 @@ u8 *nfc_llcp_general_bytes(struct nfc_dev *dev, size_t *general_bytes_len)
        return local->gb;
 }
 
-int nfc_llcp_set_remote_gb(struct nfc_dev *dev, u8 *gb, u8 gb_len)
+int nfc_llcp_set_remote_gb(struct nfc_dev *dev, const u8 *gb, u8 gb_len)
 {
        struct nfc_llcp_local *local;
 
@@ -639,27 +639,27 @@ int nfc_llcp_set_remote_gb(struct nfc_dev *dev, u8 *gb, u8 gb_len)
                                     local->remote_gb_len - 3);
 }
 
-static u8 nfc_llcp_dsap(struct sk_buff *pdu)
+static u8 nfc_llcp_dsap(const struct sk_buff *pdu)
 {
        return (pdu->data[0] & 0xfc) >> 2;
 }
 
-static u8 nfc_llcp_ptype(struct sk_buff *pdu)
+static u8 nfc_llcp_ptype(const struct sk_buff *pdu)
 {
        return ((pdu->data[0] & 0x03) << 2) | ((pdu->data[1] & 0xc0) >> 6);
 }
 
-static u8 nfc_llcp_ssap(struct sk_buff *pdu)
+static u8 nfc_llcp_ssap(const struct sk_buff *pdu)
 {
        return pdu->data[1] & 0x3f;
 }
 
-static u8 nfc_llcp_ns(struct sk_buff *pdu)
+static u8 nfc_llcp_ns(const struct sk_buff *pdu)
 {
        return pdu->data[2] >> 4;
 }
 
-static u8 nfc_llcp_nr(struct sk_buff *pdu)
+static u8 nfc_llcp_nr(const struct sk_buff *pdu)
 {
        return pdu->data[2] & 0xf;
 }
@@ -801,7 +801,7 @@ out:
 }
 
 static struct nfc_llcp_sock *nfc_llcp_sock_get_sn(struct nfc_llcp_local *local,
-                                                 u8 *sn, size_t sn_len)
+                                                 const u8 *sn, size_t sn_len)
 {
        struct nfc_llcp_sock *llcp_sock;
 
@@ -815,9 +815,10 @@ static struct nfc_llcp_sock *nfc_llcp_sock_get_sn(struct nfc_llcp_local *local,
        return llcp_sock;
 }
 
-static u8 *nfc_llcp_connect_sn(struct sk_buff *skb, size_t *sn_len)
+static const u8 *nfc_llcp_connect_sn(const struct sk_buff *skb, size_t *sn_len)
 {
-       u8 *tlv = &skb->data[2], type, length;
+       u8 type, length;
+       const u8 *tlv = &skb->data[2];
        size_t tlv_array_len = skb->len - LLCP_HEADER_SIZE, offset = 0;
 
        while (offset < tlv_array_len) {
@@ -875,7 +876,7 @@ static void nfc_llcp_recv_ui(struct nfc_llcp_local *local,
 }
 
 static void nfc_llcp_recv_connect(struct nfc_llcp_local *local,
-                                 struct sk_buff *skb)
+                                 const struct sk_buff *skb)
 {
        struct sock *new_sk, *parent;
        struct nfc_llcp_sock *sock, *new_sock;
@@ -893,7 +894,7 @@ static void nfc_llcp_recv_connect(struct nfc_llcp_local *local,
                        goto fail;
                }
        } else {
-               u8 *sn;
+               const u8 *sn;
                size_t sn_len;
 
                sn = nfc_llcp_connect_sn(skb, &sn_len);
@@ -1112,7 +1113,7 @@ static void nfc_llcp_recv_hdlc(struct nfc_llcp_local *local,
 }
 
 static void nfc_llcp_recv_disc(struct nfc_llcp_local *local,
-                              struct sk_buff *skb)
+                              const struct sk_buff *skb)
 {
        struct nfc_llcp_sock *llcp_sock;
        struct sock *sk;
@@ -1155,7 +1156,8 @@ static void nfc_llcp_recv_disc(struct nfc_llcp_local *local,
        nfc_llcp_sock_put(llcp_sock);
 }
 
-static void nfc_llcp_recv_cc(struct nfc_llcp_local *local, struct sk_buff *skb)
+static void nfc_llcp_recv_cc(struct nfc_llcp_local *local,
+                            const struct sk_buff *skb)
 {
        struct nfc_llcp_sock *llcp_sock;
        struct sock *sk;
@@ -1188,7 +1190,8 @@ static void nfc_llcp_recv_cc(struct nfc_llcp_local *local, struct sk_buff *skb)
        nfc_llcp_sock_put(llcp_sock);
 }
 
-static void nfc_llcp_recv_dm(struct nfc_llcp_local *local, struct sk_buff *skb)
+static void nfc_llcp_recv_dm(struct nfc_llcp_local *local,
+                            const struct sk_buff *skb)
 {
        struct nfc_llcp_sock *llcp_sock;
        struct sock *sk;
@@ -1226,12 +1229,13 @@ static void nfc_llcp_recv_dm(struct nfc_llcp_local *local, struct sk_buff *skb)
 }
 
 static void nfc_llcp_recv_snl(struct nfc_llcp_local *local,
-                             struct sk_buff *skb)
+                             const struct sk_buff *skb)
 {
        struct nfc_llcp_sock *llcp_sock;
-       u8 dsap, ssap, *tlv, type, length, tid, sap;
+       u8 dsap, ssap, type, length, tid, sap;
+       const u8 *tlv;
        u16 tlv_len, offset;
-       char *service_name;
+       const char *service_name;
        size_t service_name_len;
        struct nfc_llcp_sdp_tlv *sdp;
        HLIST_HEAD(llc_sdres_list);

diff --git a/net/nfc/nfc.h b/net/nfc/nfc.h
index 889fefd..de2ec66 100644 (file)
--- a/net/nfc/nfc.h
+++ b/net/nfc/nfc.h
@@ -48,7 +48,7 @@ void nfc_llcp_mac_is_up(struct nfc_dev *dev, u32 target_idx,
                        u8 comm_mode, u8 rf_mode);
 int nfc_llcp_register_device(struct nfc_dev *dev);
 void nfc_llcp_unregister_device(struct nfc_dev *dev);
-int nfc_llcp_set_remote_gb(struct nfc_dev *dev, u8 *gb, u8 gb_len);
+int nfc_llcp_set_remote_gb(struct nfc_dev *dev, const u8 *gb, u8 gb_len);
 u8 *nfc_llcp_general_bytes(struct nfc_dev *dev, size_t *general_bytes_len);
 int nfc_llcp_data_received(struct nfc_dev *dev, struct sk_buff *skb);
 struct nfc_llcp_local *nfc_llcp_find_local(struct nfc_dev *dev);