diff --git a/general/g.setproj/main.c b/general/g.setproj/main.c
index 2f6c10b0a01..716b5c5d31a 100644
--- a/general/g.setproj/main.c
+++ b/general/g.setproj/main.c
@@ -209,8 +209,9 @@ int main(int argc, char *argv[])
               1)) {
         char lbuf[100], lbufa[100];
 
-        if (exist && (G_get_datumparams_from_projinfo(old_proj_keys, lbuf,
-                                                      lbufa) == 2)) {
+        if (exist &&
+            (G_get_datumparams_from_projinfo(old_proj_keys, lbuf, sizeof(lbuf),
+                                             lbufa, sizeof(lbufa)) == 2)) {
             G_strip(lbuf);
             if ((i = G_get_datum_by_name(lbuf)) > 0) {
                 G_message(_("The current datum is %s (%s)"), G_datum_name(i),
diff --git a/include/grass/defs/gis.h b/include/grass/defs/gis.h
index 498418fb01e..9fb1bb25c73 100644
--- a/include/grass/defs/gis.h
+++ b/include/grass/defs/gis.h
@@ -299,7 +299,8 @@ int G_get_datum_by_name(const char *);
 const char *G_datum_name(int);
 const char *G_datum_description(int);
 const char *G_datum_ellipsoid(int);
-int G_get_datumparams_from_projinfo(const struct Key_Value *, char *, char *);
+int G_get_datumparams_from_projinfo(const struct Key_Value *, char *, size_t,
+                                    char *, size_t);
 void G_read_datum_table(void);
 
 /* debug.c */
diff --git a/lib/gis/datum.c b/lib/gis/datum.c
index 3c2d74ca981..cb0627be983 100644
--- a/lib/gis/datum.c
+++ b/lib/gis/datum.c
@@ -81,16 +81,19 @@ const char *G_datum_ellipsoid(int n)
 }
 
 /***********************************************************
- *  G_get_datumparams_from_projinfo(projinfo, datumname, params)
+ *  G_get_datumparams_from_projinfo(projinfo, datumname, datumname_size,
+ *                                   params, params_size)
  *     struct Key_Value *projinfo Set of key_value pairs containing
  *                       projection information in PROJ_INFO file
  *                       format
  *     char *datumname   Pointer into which a string containing
  *                       the datum name (if present) will be
  *                       placed.
+ *     size_t datumname_size  Size in bytes of the datumname buffer.
  *     char *params      Pointer into which a string containing
  *                       the datum parameters (if present) will
  *                       be placed.
+ *     size_t params_size  Size in bytes of the params buffer.
  *
  *  Extract the datum transformation-related parameters from a
  *  set of general PROJ_INFO parameters.
@@ -102,33 +105,39 @@ const char *G_datum_ellipsoid(int n)
  ************************************************************/
 
 int G_get_datumparams_from_projinfo(const struct Key_Value *projinfo,
-                                    char *datumname, char *params)
+                                    char *datumname, size_t datumname_size,
+                                    char *params, size_t params_size)
 {
     int returnval = -1;
 
     if (NULL != G_find_key_value("datum", projinfo)) {
-        sprintf(datumname, "%s", G_find_key_value("datum", projinfo));
+        snprintf(datumname, datumname_size, "%s",
+                 G_find_key_value("datum", projinfo));
         returnval = 1;
     }
 
     if (G_find_key_value("datumparams", projinfo) != NULL) {
-        sprintf(params, "%s", G_find_key_value("datumparams", projinfo));
+        snprintf(params, params_size, "%s",
+                 G_find_key_value("datumparams", projinfo));
         returnval = 2;
     }
     else if (G_find_key_value("nadgrids", projinfo) != NULL) {
-        sprintf(params, "nadgrids=%s", G_find_key_value("nadgrids", projinfo));
+        snprintf(params, params_size, "nadgrids=%s",
+                 G_find_key_value("nadgrids", projinfo));
         returnval = 2;
     }
     else if (G_find_key_value("towgs84", projinfo) != NULL) {
-        sprintf(params, "towgs84=%s", G_find_key_value("towgs84", projinfo));
+        snprintf(params, params_size, "towgs84=%s",
+                 G_find_key_value("towgs84", projinfo));
         returnval = 2;
     }
     else if (G_find_key_value("dx", projinfo) != NULL &&
              G_find_key_value("dy", projinfo) != NULL &&
              G_find_key_value("dz", projinfo) != NULL) {
-        sprintf(params, "towgs84=%s,%s,%s", G_find_key_value("dx", projinfo),
-                G_find_key_value("dy", projinfo),
-                G_find_key_value("dz", projinfo));
+        snprintf(params, params_size, "towgs84=%s,%s,%s",
+                 G_find_key_value("dx", projinfo),
+                 G_find_key_value("dy", projinfo),
+                 G_find_key_value("dz", projinfo));
         returnval = 2;
     }
 
diff --git a/lib/gis/proj3.c b/lib/gis/proj3.c
index 4c1491452c4..640d8f3f4b3 100644
--- a/lib/gis/proj3.c
+++ b/lib/gis/proj3.c
@@ -193,7 +193,8 @@ const char *G_database_datum_name(void)
     else if (!proj_info)
         return NULL;
     else
-        datumstatus = G_get_datumparams_from_projinfo(proj_info, buf, params);
+        datumstatus = G_get_datumparams_from_projinfo(
+            proj_info, buf, sizeof(buf), params, sizeof(params));
 
     if (datumstatus == 2)
         return G_store(params);