CCBC-1596: replace unsafe sprintf with snprintf

Change-Id: I26ecf01764cb8870456bef8c7666dfe262a9951d
Reviewed-on: https://review.couchbase.org/c/libcouchbase/+/190187
Tested-by: Build Bot <build@couchbase.com>
Reviewed-by: Trond Norbye <trond.norbye@couchbase.com>

Author: avsej

contrib/cJSON/cJSON.c

@@ -270,15 +270,15 @@ static char *print_number(cJSON *item)
     double d = item->valuedouble;
     if (fabs(((double)item->valueint) - d) <= DBL_EPSILON && d <= INT_MAX && d >= INT_MIN) {
         str = (char *)cJSON_malloc(21); /* 2^64+1 can be represented in 21 chars. */
-        sprintf(str, "%" PRId64, item->valueint);
+        snprintf(str, 21, "%" PRId64, item->valueint);
     } else {
         str = (char *)cJSON_malloc(64); /* This is a nice tradeoff. */
         if (fabs(floor(d) - d) <= DBL_EPSILON)
-            sprintf(str, "%.0f", d);
+            snprintf(str, 64, "%.0f", d);
         else if (fabs(d) < 1.0e-6 || fabs(d) > 1.0e9)
-            sprintf(str, "%e", d);
+            snprintf(str, 64, "%e", d);
         else
-            sprintf(str, "%f", d);
+            snprintf(str, 64, "%f", d);
     }
     return str;
 }

contrib/cliopts/cliopts.c

@@ -539,22 +539,31 @@ parse_option(struct cliopts_priv *ctx,
     return WANT_VALUE;
 }
 
+static size_t bytes_left(const char *buf, size_t capacity)
+{
+    size_t len = strlen(buf);
+    if (len >= capacity - 1) {
+        return 0;
+    }
+    return capacity - len;
+}
+
 static char *
-get_option_name(cliopts_entry *entry, char *buf)
+get_option_name(cliopts_entry *entry, char *buf, size_t capacity)
 {
     /* [-s,--option] */
     char *bufp = buf;
-    bufp += sprintf(buf, "[");
+    bufp += snprintf(buf, bytes_left(buf, capacity), "[");
     if (entry->kshort) {
-        bufp += sprintf(bufp, "-%c", entry->kshort);
+        bufp += snprintf(bufp, bytes_left(buf, capacity), "-%c", entry->kshort);
     }
     if (entry->klong) {
         if (entry->kshort) {
-            bufp += sprintf(bufp, ",");
+            bufp += snprintf(bufp, bytes_left(buf, capacity), ",");
         }
-        bufp += sprintf(bufp, "--%s", entry->klong);
+        bufp += snprintf(bufp, bytes_left(buf, capacity), "--%s", entry->klong);
     }
-    sprintf(bufp, "]");
+    snprintf(bufp, bytes_left(buf, capacity), "]");
     return buf;
 }
 
@@ -576,12 +585,12 @@ static int get_terminal_width(void)
 
 static char*
 format_option_help(cliopts_entry *entry,
-                   char *buf,
+                   char *buf, size_t capacity,
                    struct cliopts_extra_settings *settings)
 {
     char *bufp = buf;
     if (entry->kshort) {
-        bufp += sprintf(bufp, " -%c ", entry->kshort);
+        bufp += snprintf(bufp, bytes_left(buf, capacity), " -%c ", entry->kshort);
     }
 
 #define _advance_margin(offset) \
@@ -595,11 +604,11 @@ format_option_help(cliopts_entry *entry,
     _advance_margin(4)
 
     if (entry->klong) {
-        bufp += sprintf(bufp, " --%s ", entry->klong);
+        bufp += snprintf(bufp, bytes_left(buf, capacity), " --%s ", entry->klong);
     }
 
     if (entry->vdesc) {
-        bufp += sprintf(bufp, " <%s> ", entry->vdesc);
+        bufp += snprintf(bufp, bytes_left(buf, capacity), " <%s> ", entry->vdesc);
     }
 
     _advance_margin(35)
@@ -664,7 +673,7 @@ print_help(struct cliopts_priv *ctx, struct cliopts_extra_settings *settings)
         }
 
         memset(helpbuf, 0, sizeof(helpbuf));
-        format_option_help(cur, helpbuf, settings);
+        format_option_help(cur, helpbuf, sizeof(helpbuf), settings);
         fprintf(stderr, INDENT "%s", helpbuf);
 
 
@@ -728,7 +737,7 @@ print_help(struct cliopts_priv *ctx, struct cliopts_extra_settings *settings)
     }
     memset(helpbuf, 0, sizeof(helpbuf));
     fprintf(stderr, INDENT "%s\n",
-            format_option_help(&helpent, helpbuf, settings));
+            format_option_help(&helpent, helpbuf, sizeof(helpbuf), settings));
 
 }
 
@@ -747,7 +756,7 @@ dump_error(struct cliopts_priv *ctx)
     } else if (ctx->errnum == CLIOPTS_ERR_ISSWITCH) {
         char optbuf[64] = { 0 };
         fprintf(stderr, "Option %s takes no arguments",
-                get_option_name(ctx->prev, optbuf));
+                get_option_name(ctx->prev, optbuf, sizeof(optbuf)));
     }
     fprintf(stderr, "\n");
 
@@ -865,7 +874,7 @@ cliopts_parse_options(cliopts_entry *entries,
             }
 
             fprintf(stderr, "Required option %s missing\n",
-                    get_option_name(cur_ent, entbuf));
+                    get_option_name(cur_ent, entbuf, sizeof(entbuf)));
         }
     }
 

example/db/vb.c

@@ -223,8 +223,8 @@ int main(int argc, char *argv[])
         char design_path[64] = {0};
         char doc[256] = {0};
         lcb_CMDHTTP *cmd;
-        sprintf(design_path, "_design/%s", design);
-        sprintf(doc, "{\"views\":{\"all\":{\"map\":\"function(doc,meta){if(meta.id=='%s'){emit(meta.id)}}\"}}}", key);
+        snprintf(design_path, sizeof(design_path), "_design/%s", design);
+        snprintf(doc, sizeof(doc), "{\"views\":{\"all\":{\"map\":\"function(doc,meta){if(meta.id=='%s'){emit(meta.id)}}\"}}}", key);
 
         lcb_cmdhttp_create(&cmd, LCB_HTTP_TYPE_VIEW);
         lcb_cmdhttp_path(cmd, design_path, strlen(design_path));

example/subdoc/subdoc-multi.cc

@@ -144,8 +144,8 @@ int main(int argc, char **argv)
         std::string &val = bufs[(ii * 2) + 1];
         char pbuf[24], vbuf[24];
 
-        sprintf(pbuf, "pth%d", ii);
-        sprintf(vbuf, "\"Value_%d\"", ii);
+        snprintf(pbuf, sizeof(pbuf), "pth%d", ii);
+        snprintf(vbuf, sizeof(vbuf), "\"Value_%d\"", ii);
         path = pbuf;
         val = vbuf;
 
@@ -166,7 +166,7 @@ int main(int argc, char **argv)
     for (int ii = 0; ii < 5; ii++) {
         char pbuf[24];
         std::string &path = bufs[ii];
-        sprintf(pbuf, "pth%d", ii);
+        snprintf(pbuf, sizeof(pbuf), "pth%d", ii);
         path = pbuf;
 
         lcb_subdocspecs_get(specs, ii, 0, path.c_str(), path.size());

src/analytics/analytics_handle.cc

@@ -194,7 +194,7 @@ lcb_ANALYTICS_HANDLE_::lcb_ANALYTICS_HANDLE_(lcb_INSTANCE *obj, void *user_cooki
         // Set the default timeout as the server-side query timeout if no
         // other timeout is used.
         char buf[64] = {0};
-        sprintf(buf, "%uus", LCBT_SETTING(obj, analytics_timeout));
+        snprintf(buf, sizeof(buf), "%uus", LCBT_SETTING(obj, analytics_timeout));
         tmoval = buf;
         timeout_ = LCBT_SETTING(obj, analytics_timeout);
     } else if (tmoval.isString()) {

src/config_static.h

@@ -115,6 +115,7 @@
 
 #if defined(_MSC_VER) && _MSC_VER < 1900
 #define snprintf _snprintf
+#define vsnprintf _vsnprintf
 #endif
 
 #define strcasecmp(a, b) _stricmp(a, b)

src/hostlist.cc

@@ -142,7 +142,7 @@ lcb_STATUS lcb_host_parse(lcb_host_t *host, const char *spec, int speclen, int d
     if (*port_s) {
         strcpy(host->port, port_s);
     } else {
-        sprintf(host->port, "%d", deflport);
+        snprintf(host->port, sizeof(host->port), "%d", deflport);
     }
     host->ipv6 = ipv6;
 

src/http/http.cc

@@ -712,7 +712,7 @@ lcb_STATUS Request::setup_inputs(const lcb_CMDHTTP *cmd)
 
     if (!body.empty()) {
         char lenbuf[64];
-        sprintf(lenbuf, "%lu", (unsigned long int)body.size());
+        snprintf(lenbuf, sizeof(lenbuf), "%lu", (unsigned long int)body.size());
         add_header("Content-Length", lenbuf);
         if (cmd->content_type) {
             add_header("Content-Type", cmd->content_type);

src/n1ql/query_handle.cc

@@ -534,7 +534,7 @@ lcb_QUERY_HANDLE_::lcb_QUERY_HANDLE_(lcb_INSTANCE *obj, void *user_cookie, const
     Json::Value &tmoval = json["timeout"];
     if (tmoval.isNull()) {
         char buf[64] = {0};
-        sprintf(buf, "%uus", timeout);
+        snprintf(buf, sizeof(buf), "%uus", timeout);
         tmoval = buf;
         json["timeout"] = buf;
     } else if (tmoval.isString()) {

src/operations/stats.cc

@@ -187,7 +187,7 @@ lcb_STATUS lcb_stats(lcb_INSTANCE *instance, void *cookie, const lcb_CMDSTATS *c
                 return LCB_ERR_INVALID_ARGUMENT;
             }
         }
-        sprintf(ksbuf, "key %.*s %d", (int)kbuf_in->nbytes, (const char *)kbuf_in->bytes, vbid);
+        snprintf(ksbuf, sizeof(ksbuf), "key %.*s %d", (int)kbuf_in->nbytes, (const char *)kbuf_in->bytes, vbid);
         kbuf_out.contig.nbytes = strlen(ksbuf);
         kbuf_out.contig.bytes = ksbuf;
     } else {