checkpolicy: handle unprintable token

In case the erroneous token is unprintable, e.g. a control character, print its hex value instead. Signed-off-by: Christian Göttsche <[email protected]> Acked-by: James Carter <[email protected]>
SELinuxProject · Mar 27, 2024 · 39b3cc5 · 39b3cc5
1 parent ca77c59
commit 39b3cc5
Showing 1 changed file with 11 additions and 1 deletion.
diff --git a/checkpolicy/policy_scan.l b/checkpolicy/policy_scan.l
@@ -320,14 +320,24 @@ GLBLUB { return(GLBLUB); }
 int yyerror(const char *msg)
 {
 #ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ const char *token;
+ char buf[8];
+
+ if (isprint((unsigned char)yytext[0])) {
+ token = yytext;
+ } else {
+ snprintf(buf, sizeof(buf), "%#x", yytext[0]);
+ token = buf;
+ }
+
  if (source_file[0])
  fprintf(stderr, "%s:%lu:",
  source_file, source_lineno);
  else
  fprintf(stderr, "(unknown source)::");
  fprintf(stderr, "ERROR '%s' at token '%s' on line %lu:\n%s\n%s\n",
  msg,
- yytext,
+ token,
  policydb_lineno,
  linebuf[0], linebuf[1]);
 #else