hs20-osu-client: Check snprintf result to avoid compiler warnings

Fix false positive warnings by gcc 8.3.0.

Signed-off-by: Masashi Honma <masashi.honma@gmail.com>

diff --git a/hs20/client/osu_client.c b/hs20/client/osu_client.c
index 1f594ce8a25ae2159c65880aebd760caa0d041bc..fd99600da7880a7c36aa407e4e01edf01384d3cc 100644 (file)
--- a/hs20/client/osu_client.c
+++ b/hs20/client/osu_client.c
@@ -1588,6 +1588,7 @@ static void set_pps_cred_digital_cert(struct hs20_osu_client *ctx, int id,
                                      xml_node_t *node, const char *fqdn)
 {
        char buf[200], dir[200];
+       int res;
 
        wpa_printf(MSG_INFO, "- Credential/DigitalCertificate");
 
@@ -1599,14 +1600,20 @@ static void set_pps_cred_digital_cert(struct hs20_osu_client *ctx, int id,
                wpa_printf(MSG_INFO, "Failed to set username");
        }
 
-       snprintf(buf, sizeof(buf), "%s/SP/%s/client-cert.pem", dir, fqdn);
+       res = os_snprintf(buf, sizeof(buf), "%s/SP/%s/client-cert.pem", dir,
+                         fqdn);
+       if (os_snprintf_error(sizeof(buf), res))
+               return;
        if (os_file_exists(buf)) {
                if (set_cred_quoted(ctx->ifname, id, "client_cert", buf) < 0) {
                        wpa_printf(MSG_INFO, "Failed to set client_cert");
                }
        }
 
-       snprintf(buf, sizeof(buf), "%s/SP/%s/client-key.pem", dir, fqdn);
+       res = os_snprintf(buf, sizeof(buf), "%s/SP/%s/client-key.pem", dir,
+                         fqdn);
+       if (os_snprintf_error(sizeof(buf), res))
+               return;
        if (os_file_exists(buf)) {
                if (set_cred_quoted(ctx->ifname, id, "private_key", buf) < 0) {
                        wpa_printf(MSG_INFO, "Failed to set private_key");
@@ -1620,6 +1627,7 @@ static void set_pps_cred_realm(struct hs20_osu_client *ctx, int id,
 {
        char *str = xml_node_get_text(ctx->xml, node);
        char buf[200], dir[200];
+       int res;
 
        if (str == NULL)
                return;
@@ -1634,7 +1642,9 @@ static void set_pps_cred_realm(struct hs20_osu_client *ctx, int id,
 
        if (getcwd(dir, sizeof(dir)) == NULL)
                return;
-       snprintf(buf, sizeof(buf), "%s/SP/%s/aaa-ca.pem", dir, fqdn);
+       res = os_snprintf(buf, sizeof(buf), "%s/SP/%s/aaa-ca.pem", dir, fqdn);
+       if (os_snprintf_error(sizeof(buf), res))
+               return;
        if (os_file_exists(buf)) {
                if (set_cred_quoted(ctx->ifname, id, "ca_cert", buf) < 0) {
                        wpa_printf(MSG_INFO, "Failed to set CA cert");
@@ -2717,6 +2727,8 @@ static int cmd_pol_upd(struct hs20_osu_client *ctx, const char *address,
 
        if (!pps_fname) {
                char buf[256];
+               int res;
+
                wpa_printf(MSG_INFO, "Determining PPS file based on Home SP information");
                if (address && os_strncmp(address, "fqdn=", 5) == 0) {
                        wpa_printf(MSG_INFO, "Use requested FQDN from command line");
@@ -2737,8 +2749,13 @@ static int cmd_pol_upd(struct hs20_osu_client *ctx, const char *address,
                            "SP/%s/pps.xml", ctx->fqdn);
                pps_fname = pps_fname_buf;
 
-               os_snprintf(ca_fname_buf, sizeof(ca_fname_buf), "SP/%s/ca.pem",
-                           buf);
+               res = os_snprintf(ca_fname_buf, sizeof(ca_fname_buf),
+                                 "SP/%s/ca.pem", buf);
+               if (os_snprintf_error(sizeof(ca_fname_buf), res)) {
+                       os_free(ctx->fqdn);
+                       ctx->fqdn = NULL;
+                       return -1;
+               }
                ca_fname = ca_fname_buf;
        }