Preserve the column and error message when there is a syntax error.

This information is now included in the error mail sent to root.

plugins/sudoers/check_aliases.c

@@ -1,7 +1,8 @@
 /*
  * SPDX-License-Identifier: ISC
  *
- * Copyright (c) 2004-2005, 2007-2018 Todd C. Miller <Todd.Miller@sudo.ws>
+ * Copyright (c) 2004-2005, 2007-2018, 2021-2022
+ *	Todd C. Miller <Todd.Miller@sudo.ws>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -102,6 +103,8 @@ check_alias(struct sudoers_parse_tree *parse_tree,
 	    if (strict && errorfile == NULL) {
 		errorfile = sudo_rcstr_addref(file);
 		errorlineno = line;
+		errorcolumn = column;
+		/* No need to set errorstring, visudo doesn't use it. */
 	    }
 	    alias_warned_add(warned, name);
 	}

plugins/sudoers/cvtsudoers.c

@@ -757,15 +757,7 @@ parse_sudoers(const char *input_file, struct cvtsudoers_config *conf)
 	if ((errorfile = sudo_rcstr_dup(input_file)) == NULL)
 	    sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
     }
-    if (parse_error) {
-	if (errorlineno != -1)
-	    sudo_warnx(U_("parse error in %s near line %d\n"),
-		errorfile, errorlineno);
-	else if (errorfile != NULL)
-	    sudo_warnx(U_("parse error in %s\n"), errorfile);
-	debug_return_bool(false);
-    }
-    debug_return_bool(true);
+    debug_return_bool(!parse_error);
 }
 
 FILE *

plugins/sudoers/file.c

@@ -104,11 +104,12 @@ sudo_file_parse(struct sudo_nss *nss)
     error = sudoersparse();
     if (error || parse_error) {
 	if (errorlineno != -1) {
-	    log_warningx(SLOG_SEND_MAIL|SLOG_NO_STDERR,
-		N_("parse error in %s near line %d"), errorfile, errorlineno);
+	    log_warningx(SLOG_SEND_MAIL|SLOG_NO_STDERR, N_("%s:%d:%d: %s"),
+		errorfile, errorlineno, errorcolumn,
+		errorstring ? errorstring : N_("syntax error"));
 	} else {
-	    log_warningx(SLOG_SEND_MAIL|SLOG_NO_STDERR,
-		N_("parse error in %s"), errorfile);
+	    log_warningx(SLOG_SEND_MAIL|SLOG_NO_STDERR, N_("%s: %s"),
+		errorfile, errorstring ? errorstring : N_("syntax error"));
 	}
 	if (error || !sudoers_recovery) {
 	    /* unrecoverable error */

plugins/sudoers/gram.h

@@ -171,7 +171,7 @@ extern int sudoersdebug;
 #if ! defined YYSTYPE && ! defined YYSTYPE_IS_DECLARED
 union YYSTYPE
 {
-#line 86 "gram.y"
+#line 88 "gram.y"
 
     struct cmndspec *cmndspec;
     struct defaults *defaults;

plugins/sudoers/gram.y

@@ -52,7 +52,9 @@ bool sudoers_warnings = true;
 bool sudoers_strict = false;
 bool parse_error = false;
 int errorlineno = -1;
+int errorcolumn = -1;
 char *errorfile = NULL;
+char *errorstring = NULL;
 
 static int alias_line, alias_column;
 
@@ -1168,13 +1170,26 @@ group		:	ALIAS {
 void
 sudoerserrorf(const char *fmt, ...)
 {
+    va_list ap;
     debug_decl(sudoerserrorf, SUDOERS_DEBUG_PARSER);
 
     /* Save the line the first error occurred on. */
     if (errorlineno == -1) {
-	errorlineno = this_lineno;
 	sudo_rcstr_delref(errorfile);
 	errorfile = sudo_rcstr_addref(sudoers);
+	errorlineno = this_lineno;
+	errorcolumn = sudolinebuf.toke_start + 1;
+	if (fmt != NULL) {
+	    va_start(ap, fmt);
+	    if (strcmp(fmt, "%s") == 0) {
+		/* Optimize common case, a single string. */
+		errorstring = strdup(_(va_arg(ap, char *)));
+	    } else {
+		if (vasprintf(&errorstring, fmt, ap) == -1)
+		    errorstring = NULL;
+	    }
+	    va_end(ap);
+	}
     }
     if (sudoers_warnings && fmt != NULL) {
 	LEXTRACE("<*> ");
@@ -1182,7 +1197,6 @@ sudoerserrorf(const char *fmt, ...)
 	if (trace_print == NULL || trace_print == sudoers_trace_print) {
 	    char *s, *tofree = NULL;
 	    int oldlocale;
-	    va_list ap;
 
 	    /* Warnings are displayed in the user's locale. */
 	    sudoers_setlocale(SUDOERS_LOCALE_USER, &oldlocale);
@@ -1754,6 +1768,9 @@ init_parser(const char *path, bool quiet, bool strict)
 
     parse_error = false;
     errorlineno = -1;
+    errorcolumn = -1;
+    free(errorstring);
+    errorstring = NULL;
     sudo_rcstr_delref(errorfile);
     errorfile = NULL;
     sudoers_warnings = !quiet;

plugins/sudoers/sudoers.h

@@ -312,6 +312,8 @@ int sudoersparse(void);
 extern char *login_style;
 extern char *errorfile;
 extern int errorlineno;
+extern int errorcolumn;
+extern char *errorstring;
 extern bool parse_error;
 extern bool sudoers_warnings;
 extern bool sudoers_recovery;

plugins/sudoers/visudo.c

@@ -564,7 +564,7 @@ done:
 
 /*
  * Check Defaults and Alias entries.
- * Sets parse_error on error and errorfile/errorlineno if possible.
+ * Sets parse_error on error and error{file,lineno,column} if possible.
  */
 static void
 check_defaults_and_aliases(bool strict, bool quiet)
@@ -576,12 +576,14 @@ check_defaults_and_aliases(bool strict, bool quiet)
 	sudo_rcstr_delref(errorfile);
 	errorfile = NULL;
 	errorlineno = -1;
+	errorcolumn = -1;
 	/* XXX - should edit all files with errors */
 	TAILQ_FOREACH(d, &parsed_policy.defaults, entries) {
-	    if (d->error) {
-		/* Defaults parse error, set errorfile/errorlineno. */
+	    if (d->error && errorlineno == -1) {
+		/* Defaults parse error, set error{file,lineno,column}. */
 		errorfile = sudo_rcstr_addref(d->file);
 		errorlineno = d->line;
+		errorcolumn = d->column;
 		break;
 	    }
 	}