diff --git a/src/nvim/tag.c b/src/nvim/tag.c
index 7dd4cd39d1..17ca81ed0a 100644
--- a/src/nvim/tag.c
+++ b/src/nvim/tag.c
@@ -2500,7 +2500,7 @@ int get_tagfname(tagname_T *tnp, int first, char *buf)
         return FAIL;
       }
       tnp->tn_hf_idx++;
-      STRCPY(buf, p_hf);
+      xstrlcpy(buf, p_hf, MAXPATHL);
       STRCPY(path_tail(buf), "tags");
 #ifdef BACKSLASH_IN_FILENAME
       slash_adjust(buf);
diff --git a/test/old/testdir/test_help.vim b/test/old/testdir/test_help.vim
index e2ae06d486..c9371221d1 100644
--- a/test/old/testdir/test_help.vim
+++ b/test/old/testdir/test_help.vim
@@ -296,4 +296,13 @@ func Test_help_command_termination()
   helpclose
 endfunc
 
+" This caused a buffer overflow
+func Test_helpfile_overflow()
+  let _helpfile = &helpfile
+  let &helpfile = repeat('A', 5000)
+  help
+  helpclose
+  let &helpfile = _helpfile
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab